Featured scientist: interview with Prof Daniel Mario Ugarte.

Posted on Wednesday 30 de January de 2019

Prof. Daniel Ugarte in one of his two favorite activities: cooking. The other one is experimental research.

Daniel Mario Ugarte was born on March 23, 1963 in Cosquín, a small town in the mountains of the province of Córdoba (Argentina). He grew up in a family environment that was very stimulating to curiosity, learning and experimentation. After completing his elementary and secondary education in this city, he studied physics in the province’s capital, at the National University of Cordoba, the oldest in the neighboring country (founded in 1613). After graduation, he completed an internship in transmission electron microscopy at Université Paris-Sud, France, where he ended up doing his doctorate in nanoscience subjects (although at that time the “nano” prefix was not yet widely used). Ugarte received his Ph.D. in physics in 1990. He moved to Switzerland where he completed a post-doctorate internship lasting about three years at the École Polytechnique Fédérale de Lausanne (EPFL). There he continued to do nanoscience and nanotechnology and obtained results with great academic impact, notably the “nano-onions of fullerene”, which earned him, at the age of 29, his first article in the journal Nature, signed by him alone and highlighted in the cover of the issue. This paper, which today has more than 2,000 citations, would be the first of six articles published by Ugarte in the two main scientific journals of the world (Science and Nature), among dozens of publications in specialized scientific journals, also of very high impact, such as Nature Nanotechnology, Nano Letters, Physical Review Letters, among others.

In 1993, for personal reasons, Ugarte went to live in Brazil, and began to work with the team that was beginning the construction of the National Synchrotron Light Laboratory (LNLS) at the current site, in the city of Campinas (São Paulo state). It was in this context that he was able to make real his idea of constructing an electron microscope laboratory for research and training really open to the entire scientific community, including students. The Laboratory of Electronic Microscopy began its activities in 1999, directed by the Cordoban scientist, and was the seed of the current National Nanotechnology Laboratory (LNNano). Between 1994 and 1998, Ugarte also served as visiting professor at EPFL. In 2004, he left LNLS to take up the position of associate professor at the Gleb Wataghin Institute of Physics (IFGW), State University of Campinas (UNICAMP). Since 2007, he is a full professor of this institution. In addition, from 2004 to 2007, Professor Ugarte coordinated a research network on nanomaterials, NANOMAT, which included 23 institutions and 150 researchers.

Throughout his scientific career, Daniel Ugarte has delivered more than 100 invited lectures at international scientific events and received several prestigious awards for his exceptional academic contributions, such as the Prix Latsis Universitaire EPFL (Switzerland, 1994), the John Simon Guggenheim Fellowship (USA, 2002), the Scopus Brazil Award from Elsevier and CAPES (Brazil, 2008) and the Physics Award from The World Academy of Sciences, TWAS (Italy, 2018). In 2012, Ugarte was elected a member of the Brazilian Academy of Sciences (ABC). In addition, several students guided by him received prizes for their PhD theses, granted by the Presidency of the Republic, CAPES, the Brazilian Society of Physics (SBF) and the IFGW – UNICAMP.

Daniel Ugarte is the author of more than 100 articles published in international peer-reviewed journals. According to Google Scholar, his academic production received more than 16,600 citations and his h-index is 43.

Take a look at our interview with this founding member of B-MRS and learn more about his life story, his key findings, his criticisms of some trends in how to make science and his message to younger researchers.

B-MRS Newsletter: – We would like to know how / why you became a scientist. When did the desire to be a scientist come to you?

Daniel Ugarte: – I was born in Argentina, with the genetic information typical of that country: mother of Italian origin, and father of Spanish origin (Basque, to be precise), but trying to be English (I love rugby). I think the example of my parents’ curiosity, work, and varied interests had a majority influence on my choices. I was born and raised in a town in the middle of mountains in Argentina (the town of Cosquín, with approximately 10,000 inhabitants, in the province of Córdoba). My mother was a teacher of elementary school and always tried, with very scarce financial resources, to obtain books to continue studying and improve her classes (at that time there was no internet); we read together these new texts of history, dinosaurs, etc. My father, even though he attended school only until he was 12 years old, was always very curious and active. He did everything as an amateur and self-taught; very active, he was an actor, a painter, a musician, he repaired everything, made keys etc. Curiosity and childish spirit were always with him: every new thing, he wanted to dismount to see how it worked. If I had to define his profession, I would say that he made publicity posters. In his workshop, all the equipment was built by himself. In that room of constant mess, I played drilling irons, soldering wires, cutting wood, hammering things. We had few luxuries, no expensive toys, but there were always books, and I did very unusual things (supervised by my parents) in the eyes of other children, such as model airplanes, galena radios, a telescope, etc. With my mother, we always cooked new recipes (gnocchi, cakes, alfajores, sweets, etc.); at 10 years old, every Sunday at noon, I prepared the family barbecue. These experiments of chemistry and heat were very instructive (and tasty), flavors and aromas that I still try to reproduce accurately today. Finally, to complete, I was lucky enough to have some ease with logic and mathematics, which was in evidence when I went to school. I have to thank the Science and Mathematics teachers who worked hard to keep my motivation in that little town so that I could grow and develop this incipient talent. I think that with this childhood, the dream of doing science and working in a laboratory (or a kitchen) making discoveries and building wonderful instruments is the most natural consequence of the world (I must clarify that outside the laboratory my main hobby is to cook).

B-MRS Newsletter: – Briefly tell us what led you to work in the field of nanosystems.

Daniel Ugarte: – In fact I arrived in the “nano” world through electron microscopy. At the Universidad Nacional de Córdoba I studied physics, much more interested in the experimental profile and in the laboratory work using the hands. In the course, you must do a final dissertation to obtain your diploma. Among the various options of the Institute of Physics, I preferred to do a project associated with scanning electron microscopy and X-ray spectroscopy. A pragmatic choice aiming at having more employment options after my graduation. At that moment, I was lucky, an opportunity arose to go to France to do an internship in transmission electron microscopy, and after arriving there (Laboratoire de Physique des Solides, Université Paris-Sud, Orsay), I was invited to do a doctoral thesis to study the excitation of surface plasmas in small particles (in English at the time they were “small particles”, not “nanoparticles” as it is today). The term “nano” did not yet exist, and “plasmon” was only a curiosity (today it is one of the most active nanoscience themes). Once I finished my thesis, I was able to get a postdoctoral fellowship in Switzerland, in one of the first institutes to focus on the new properties of particle size reduction (Institut de Physique Experimentale, Ecole Polytechnique Féderale de Lausanne). In short, I started in the nano embryos and always continued to study small systems with high spatial resolution techniques associated with transmission electron microscopy. The atomic or nanometric resolution of this technique is imperative for basic or technological research in nanosystems, and expensive microscopes have become symbols to display the richness of each “nano” program.

B-MRS Newsletter: – What are your main scientific and technological contributions to the Materials area in your own assessment and why do you consider them to be the most relevant?

Daniel Ugarte: – Carbon nanostructures (fullerenes, nanotubes, graphene) represent a typical example of nanomaterials with novel properties. Considering dates, fullerenes were discovered in 1986, the solid of fullerenes in 1990, the nanotubes in 1991. Working in Switzerland in 1992, I accidentally observed that by irradiating carbon materials with the electron beam of a transmission electron microscope, everything turned into “fullerene onions” (concentric graphite spheres, like a Russian doll). This experiment generated a new member for the newly discovered fullerene family, and the work had an incredible repercussion worldwide. However, the interesting thing was that this was not my postdoctoral project, which was a research focused in the study of electronic diffraction of metallic nanoparticles. In Lausanne we had a complete microscopy lab with all the border equipment. And I noticed that no one wore them at night, so I decide to go and play there … to make exploratory, innocent, alternative experiments and, unintentionally, the onions appeared …. But when I first spoke of the results no one believed; a reviewer for the prestigious journal Physical Review Letters said that my data was as ridiculous as cold fusion (a highly controversial subject at that time); that was an insult of the worst level. But I kept defending my job, I got the same results over and over again, and they were the truth. I continued presenting the result in the conferences; I survived many violent and humiliating comments. To make things a bit out of the paradigm one must have “hard leather”. Finally, with the unexpected and spontaneous support of Sir Harry Kroto (who received the Nobel Prize in Chemistry in 1996), who did not know me and never spoke to me, my article was published in the journal Nature. I was less than 30 years old, very innocent, and I was very surprised by the enormous interest of the media; I reported to many countries, among them Japan, Germany, etc. It felt like the world was falling on my head. With naive (unpretentious) and out of context experiments done at night with advanced instruments, I had created work options that knocked on my door. However, at the moment, to the surprise of my French and Swiss colleagues, I took an alternative route, and in 1993 I choose to live in Brazil for personal and family reasons.

A few years later, in 1995, we were on a Saturday afternoon at the laboratory in Lausanne, making brainstorming proposals with my friend Walt de Heer (an incredible scientist considering depth and creativity). We decided to test one that came up there at the time: using carbon nanotubes (the tip is really thin) to produce a source of electrons. We put together a hydraulic press, plumb-type teflon tape, microscope grids, old mica, some lab things (vacuum chamber, oscilloscope, etc.) and set up something awful, dirty, grotesque, completely improvised, and … it worked !!! . The result was published in the journal Science. This experiment created a new area of applied research for the carbon nanotubes that several industrial laboratories tried to explore; until today it is an active area of research. Again, in my way, another innocent experimental proposal, but creative and relaxed (in this case the result was not accidental, but planned), which captured the interest of the international technological community.

In my group in Brazil, I decided to invest in a new line of research based on an irreverent experiment proposed in Spain by a researcher called Costa-Kramer (Nanowire formation in macroscopic metallic contacts: quantum mechanical conductance tapping a table top, Surf. Sci. 1995). If we add two pieces of gold and then separate them, at the end a very thin yarn (as with chewing gum) is formed which may even have an atom of diameter. By measuring the electric current through this wire during elongation, we can study quantum effects in electrical conduction by nanostructures. In Campinas, my student Varlei Rodrigues (who later received the SBF Prize for Best Doctoral Thesis in Physics in 2003) built an instrument specifically designed to carry out this study with high precision in ultra high vacuum (UHV) conditions. Later we were able to make electron microscopic images of the atomic arrangement of the wires generated by mechanical elongation and also theoretical calculations in collaboration with the group of Douglas Galvão. From this information we could understand in detail our experimental measurements; from these results I was invited to give almost a hundred lectures at international conferences. I believe that these results were very important from the Brazilian point of view, since all the research was done in the country: ideas, advanced experiments, construction of specific scientific instrumentation, theoretical calculations and understanding. In addition to the scientific impact, the research on metallic nanowires represents an important achievement, as it allowed us to show, by example, that competitive experimental nanoscience studies can be done in the country, combining work with originality and a certain degree of risk.

Speaking of results feeds our ego (the little Argentine that we all carry inside …); another aspect of our contribution to society comes when our effort is dedicated to community growth, in particular to raise the level of science in the country. In this sense, I would like to recall one of the most comforting works of my career: the idealization and creation of a multi-user electron microscopy laboratory in Campinas. This project had the constant and unconditional support of the LNLS directors at the time (Cylon da Silva, Aldo Craievich and Ricardo Rodrigues). Finally, the microscopes were acquired with resources (many resources !!!) from The São Paulo Research Foundation (FAPESP). From the initial idea, I worked so that the laboratory was open and available to Brazilian researchers (not in intentions, but in reality) and also had the training of human resources as a focus of their activities. Contrary to the general opinion of the community, in the microscopy laboratory all the observations were made by the undergraduate or graduate students involved in the projects, after a training process. Many students learned to work, and the instruments did not break at all, but we had to give ourselves the time to teach the interested researchers. This mode of operation aimed at avoiding the feudal system (“lord of instruments”) or application of psychophanism. I stayed in this lab until 2009. This laboratory grew and became what is now called the National Nanotechnology Laboratory (LNNano).

B-MRS Newsletter: – You have an unusual amount of articles published in high-impact journals (Science, Nature, PRL …), especially in the context of developing countries. To what factors and competences do you attribute this characteristic of your scientific production?

Daniel Ugarte: – In the previous question I tried to give several examples of some important moments of my scientific activity. Workload, much study, and the courage to take risks were essential to make daring and original experiments. But there is one thing I always try to teach my students: if we do a project, he must bring a relevant contribution (if it works …). If any publication is generated, it has to contribute with new knowledge, not of a lie, but of truth. We will not only choose research topics that generate quick results; probably our study will take time, we will have to understand and deepen in a lot of new thing. We may even need to develop tools / software to answer the scientific question. And my students ask: Will it work? I say, I do not know, if I knew it would work out, it would not have any emotion, but I can guarantee that you will grow a lot and get a solid background. For example, in the topic of gold nanowires we had to respond to comments (from a competitor) on what happened to mechanical elongation at low temperature. For this, we needed to perform an extremely challenging experiment and try to observe the mechanical deformation of nanowire in situ inside the microscope at low temperature with atomic resolution using a sample holder in liquid nitrogen. The student who came across the project (Maureen Lagos, who later won the CAPES thesis award in 2012) asked me: Will it be difficult? What do you think? My answer was: I think it will not work, but to answer this to the community we must test if it works or not, go, try to do your best and good luck (you will need a lot …). To my surprise, he got the measurements, very difficult and time consuming; these studies made here in Brazil receive until today (10 years later) many praises and recognition in the scientific community.

Another aspect, other than risk or daring, is quality; every student or colleague who worked with me knows that we always do the best we can, we don´t have “more or less”. Only the best is accepted, or you have to do the experiment again until you get the highest quality. Some students hate me, but recently an alumnus of UNICAMP (now a professor in the United States) published an article in the journal Nature, and sent me a message thanking me, because today he gives great value to what he has learned with me about drawing his limits. To give total quality to all the study content, in the experiments – which are the basis in our group -, in the theoretical study, in the interpretation, in the modeling, etc. As in all professions, we build our reputation over the years, and it may be prestigious or not. It has always been a pride for my group that our colleagues and competitors receive our works with attention, believing that we have done our best for each published result (but they not always agree with our conclusions / interpretations … as everyone we have many articles rejected).

When I was part of the committee that analyzes projects at CNPq, I was surprised by the number of Brazilian researchers who publish more than, say, 50 articles a year, some of them having high administrative or management positions in Brazilian teaching or research institutions, which requires concentrated effort 24 hours a day. Considering my ability to do research, I find it totally impossible to think about producing almost one publication per week !!! And that if I stayed in the lab all day with the students. At this point I would like to return to the concept of quality, considering the number and the scientific contribution of articles generated by a group or researcher. We can assume that it follows a statistical distribution with Gaussian form described by two parameters with a mean and a width (notes from 1 to 10). I know researchers with a little incoherent production, able to do the best (work note 10), and at the same time, the worst (some papers deserve very low grade, say 1-2). Let´s consider a hypothetical group in which the average contribution to knowledge per publication is good / very good (average 6 or 7), and several dozen publications are generated. Statistically, you must publish a high-quality (top-of-the-distribution and far-out-of-the-middle) article that will get community recognition (hopefully, published in a high-impact magazine). But if you make 100 publications a year and none reaches a certain relevance in your area, our simple statistical model indicates that the average contribution of your work should be moderate. In addition, the width of the distribution can also be moderate; in this situation, the production / work is consistent, in a narrow range of quality level. The causes can be varied; in some cases, it is reasonable to associate a moderate contribution to, for example, the researcher’s youth, poor infrastructure or limited funding. The critical point is when the problem is at the root, and the causes of moderate quality are associated with scientific / technical targets of minor importance and low risk. What to expect from an environment where both funding agencies as well as the researchers themselves (not only the agencies’ fault) accept that this serious disability can be fully compensated for by the number of publications? The result will be that the numbers will increase, but the impact will decrease.

Comic strip of Argentine cartoonist Quino sent by Prof. Ugarte to represent some of his criticism to a certain way of doing science. — Comic strip of Argentine cartoonist Quino sent by Prof. Ugarte to represent some of his criticisms to a way of doing science.

Maybe I’m irresponsible, stubborn (Basque roots help), but my work over the years has followed certain standards. I prefer to make a high-gastronomic dish (sometimes half-burned) than to make hundreds of rice and beans dishes. I prefer to do less things and not have numerous irrelevant publications involving work that did not include any risk (I also have these jobs), and so take the time to update myself, challenge myself, study and see things out of my main interest. So I have the opportunity for new ideas, innocent, irresponsible, that with luck will work. It is important, first, to have clearly in mind what new / different thing we are going to do in our research; if there is nothing new / risky, how will the contribution to the generation of knowledge be? In fact, this line of thinking is not very popular if we look closely at most of the projects funded in the Brazilian community (however, many discourses and plans define it as essential). On the contrary, viability is often more important than relevance and originality. We could also mention other issues that make it difficult to increase the relevance of nanoscience research in Brazil, such as experimental physics, scientific instrumentation, multidisciplinarity, where the contrast between discourse and reality gives great sadness. As in gastronomy, I prefer “slow food”, a good dish, good wine and time to enjoy. We must stand up against “fast science” (short-term projects), as this is leading to shallow-knowledge.

It is sad to see the evolution of Brazil, the numbers grow, the impact decreases … Many can see positively the publication in journals of high impact, but not everyone agrees. Let me give you an example. I decided to study some new subjects where I consider that there are opportunities for very original and interesting things. To ask deeper questions, one must understand. Learning takes time … So, my activity report had problems to be approved for low productivity: I did not reach the average. I have never had much diplomacy or political skills, so joining all my revolt, and being Argentine and Basque at the same time, I wonder: am I terribly inefficient and should I retire, which at least allows me to maintain my spirit, my freedom and form of work intact? There are many discourses on how to stimulate cutting-edge research and train researchers; I think my way of contributing is to work “in my own way” and to give an example to anyone who considers it valid.

I cannot forget to thank CNPq’s Universal system, where I know I can always send crazy ideas, and the review system respects my story and relies on my “irresponsibility”. It’s little money (if compared to international standards), but I get a lot of freedom !!!, and that’s essential to be creative!!!

B-MRS Newsletter: – Now we invite you to leave a message for readers who are starting their scientific careers.

Daniel Ugarte: – Scientific work requires being dreamy and passionate, a lot of effort in study and work. We have to be able to associate knowledge, originality, infrastructure, technical ability, etc. I think it is very important to show young people that it is possible to dream and do cutting-edge research in Brazil. The scientific milieu can be very aggressive, but we must be clear that merit is the most important parameter, and that although the research environment is extremely competitive, it is essential to develop our activities while maintaining the human qualities, professionalism and ethics.

Throughout a scientific career we must face many different situations. My academic life in Brazil had many stages, some were resplendent, with work, challenges, productivity and with excellent and motivated students (the laboratory was paradise). But I also experienced very sad, disappointing stages associated with local mediocracies. However, the stones thrown in our path have been completely overcome by our work, our results and our ethics. Always, always, merit and competence will win in the game of science.

Featured paper: Nanoclays to overcome toxicity.

Posted on Tuesday 29 de January de 2019

[Paper: Reaching Biocompatibility with Nanoclays: Eliminating the Cytotoxicity of Ir(III) Complexes. Malte C. Grüner, Kassio P. S. Zanoni, Camila F. Borgognoni, Cristiane C. Melo, Valtencir Zucolotto, and Andrea S. S. de Camargo. ACS Applied Materials & Interfaces 2018 10 (32), 26830-26834. DOI: 10.1021/acsami.8b10842.]

Nanoclays to overcome toxicity

Working in laboratories of the São Carlos Institute of Physics (IFSC – USP), a scientific team developed a strategy that eliminates the cytotoxicity (ability to destroy cells) of a group of compounds with very interesting photophysical properties for health applications . The study made viable the use of these substances, once toxic, in the study of living organisms and in the diagnosis and treatment of diseases. In addition to eliminating cytotoxicity, the strategy modifies some properties of compounds by adding new functions that can be harnessed for intracellular oxygen sensing and to improve the efficiency of luminescent devices such as OLEDs.

The work was reported in an article recently published in the journal ACS Applied Materials and Interfaces (impact factor 8,097).

It all started in an informal conversation between three postdoctoral fellows linked to IFSC-USP laboratories: Malte C. Grüner and Kassio P. S. Zanoni, both linked to the Laboratory of Functional Materials Spectroscopy (LEMAF), and Camila F. Borgognoni of the Group of Nanomedicine and Nanotoxicology (Gnano). Zanoni had worked with iridium (III) complexes during his doctorate, and wanted to take advantage of some properties of these compounds to use them as photodynamic therapy agents. Such therapy refers to a set of treatments for diseased tissues, such as those affected by cancer, in which an external radiation source is used for the activation at the appropriate time of a compound inserted into the body, which is responsible to destroy the cells that need to be eliminated.

The post-doc Zanoni’s desire, however, came up against the high cytotoxicity of iridium (III) complexes. The postdoc Grüner then had the innovative idea of trying to use laponites (materials he had studied in his doctorate) to inhibit the cytotoxicity of the compounds. From this idea, Grüner and Zanoni carried out the preparation and characterization of the materials in LEMAF, coordinated by Prof. Andrea S. S. de Camargo. At GNano, coordinated by Prof. Valtencir Zucolotto, the post-doc Borgognoni and the student Cristiane Melo were in charge to investigate the interactions of the nanoparticles with the cells.

The authors of the paper. From the left: Kassio Zanoni, Camila Borgognoni, Malte Grüner, Cristiane Melo, Valtencir Zucolotto, and Andrea de Camargo.

Strategy and applications

Illustration of the adsorption of Ir (III) complexes (blue spheres) on the surface of laponite nanodisks (yellow disks), in solution.

One of the main properties of iridium (III) complexes is their intense luminescence (emission of light not resulting from heat) in a wide range of colors. This feature may be useful for illuminating cells within living organisms in bioimaging techniques, used for both research and for diagnosis and treatment of diseases.

In turn, laponites, which are synthetic nanoclays fully compatible with living tissues, have often been proposed in the scientific literature as nanoplataforms for transporting drugs and other compounds within living organisms. The laponites are about 25 nm in length and only 1 nm in height.

In the work of the IFSC-USP team, a new material was developed as a result of the adsorption of iridium (III) complex molecules on the surface of laponite nanodiscs.

The researchers found in the laboratory (in vitro) the ability of the new material to be absorbed by cells, its luminescence within cells and its low citotoxicity. For this, they used liver cells and observed their interaction with the new nanomaterial, comparing it with the interaction with the pure iridium (III) complex. The results were highly favorable to iridium (III) laponite nanodiscs, which proved to be harmless to the cells, besides presenting good penetration and high luminescence – characteristics that make them very suitable for application in bioimaging techniques.

Light emission in various colors of the developed nanomaterials (Ir (III) complexes adsorbed on laponite) distributed in xerogels (upper part) and in liver tissue cells (lower part).

“In this work, it was demonstrated for the first time that the adsorption of iridium (III) complexes (in general, highly toxic) on the surface of laponite nanodisks is capable to completely extinguish the cytotoxicity of these compounds “, summarizes the post-doc Kassio Zanoni , who in 2017 was the winner of B-MRS Young Researcher Award. “This makes it highly feasible to use previously toxic compounds in cell media without impairing the integrity of the medium and therefore has the potential to expand the research of new biocompatible materials for use in cell mapping, theranostics and photodynamic therapy”, he adds.

According to the authors, the new nanomaterial could act as a photodynamic therapy drug, since, when irradiated with certain types of radiation, it produces a molecule (the singlet oxygen) that acts in the destruction of cancer cells. In this way, the nanomaterial also becomes promising in the field of theranostics, which proposes the combination, on the same platform, of the diagnosis of diseases by bioimaging with its cure through photodynamic therapies.

In addition, the nanomaterial can be used as a sensor to accurately determine the amount of oxygen distributed inside a cell. “As demonstrated in our work, the emission intensity of this nanomaterial is a variable as a function of the concentration of oxygen”, justifies Zanoni.

Finally, the nanomaterial, in the form of a thin nanometric film, could also be applied to organic light-emitting diodes (OLEDs) – devices that are already used, for example, in cellular screens. “This is because the iridium (III) complex adsorbed on laponite aggregates photophysical, photochemical and electrochemical properties that are strategic for the development of more efficient devices”, explains Zanoni.

This research was carried out with funding from The São Paulo Research Foundation (FAPESP).

B-MRS member is distinguished with the title of Professor Honoris Causa of the Federal University of Ceará.

Posted on Friday 11 de January de 2019

Professor Oswaldo Luiz Alves (IQ – UNICAMP), a member of B-MRS, was awarded the title of Professor Honoris Causa of the Federal University of Ceará (UFC). The title was granted by the University Council of the institution on December 17, 2018. In addition to being a full professor of UNICAMP, Alves has been a collaborating professor of the Graduate Program in Physics of UFC for more than 30 years.

In October 2018, Professor Alves received another important distinction, the admission to the Brazilian National Order of Scientific Merit in the Grand Cross class.

B-MRS Newsletter. Year 5, issue 12.

Posted on Friday 21 de December de 2018

Newsletter of the
Brazilian Materials
Research Society

Year 5, issue 12. December 21, 2018.

New Year Message

With this New Year Message, I greet the entire B-MRS community in Brazil and abroad.

Reinstating the budget is merely the first and most urgent step given the situation of universities and research centers in the country. Also important and part of B-MRS ‘s suggestions is the emphasis on partnerships between ministries to address the problems of society at large, which always entail knowledge, technology and innovation, and the search for synergy with the private sector to transform knowledge into wealth and social well-being.

The materials area in particular has proved to be essential for any and all development. From fundamental discoveries of basic science for the understanding of nature and the conquest of space, to applications in medicine and agriculture, areas that today advance significantly from new materials and methodologies created to study them. In Brazil, for example, the inauguration of the first phase of Sirius, a new source of synchrotron light, at the National Center for Research in Energy and Materials, revealed a masterpiece of materials science and engineering. Even more relevant is that much of this technology is Brazilian.

B-MRS has continuously strived to provide space for researchers from Brazil and abroad to communicate and discuss their scientific and technological contributions and to seek partnerships for new challenges in a highly multidisciplinary field. Our last meeting in Natal (RN), in September 2018, repeated the success of previous editions with this perspective. Some of the many advances in materials science and technology have been highlighted in the B-MRS Newsletters, as a sample of the quality work being done in Brazil. B-MRS also considers scientific dissemination as strategic. In 2018 it created a new section of the Newsletter, entitled “From idea to innovation,” with special reports on the effect of technologies that reached society.

I end by thanking the B-MRS community, wishing all much health and success in 2019, and hoping to meet many of you in our next Meeting at Balneário Camboriú (SC), September 22-26.

Professor Osvaldo Novais de Oliveira Junior
President of B-MRS

XVIII B-MRS Meeting/ Encontro da SBPMat
(Balneário Camboriú, SC, Brazil, September 22 – 26, 2019)

The event website is up and running! www.sbpmat.org.br/18encontro/

Symposia. 23 symposia proposed by the international scientific community were approved by the organization and comprise this edition of the event. See the symposia list, here.

Abstract submission. The submission of abstracts is open until April 15. Approval, modification, or rejection notifications will be sent by May 31. Final notices for abstracts needing modification will be sent by June 21.

Student awards. To participate in the Bernhard Gross Award, authors must submit an extended abstract by July 11 in addition to the conventional abstract. Learn more, here.

Registrations. Registration is now open. More information, here.

Venue. The meeting will be held in the delightful Balneário Camboriú (State of Santa Catarina, Brazil), at the Hotel Sibara Flat & Conventions, located in the center of the city, close to many hotels, restaurants and shops, and only 100 meters from the sea. More information, here.

Memorial lecture. The traditional Memorial Lecture Joaquim da Costa Ribeiro will be given by Professor Yvonne Primerano Mascarenhas (IFSC – USP).

Plenary lectures. Leading scientists from institutions in Germany, Italy, Spain and the United States will deliver plenary talks on border issues at the event. There will also be a plenary session by the Brazilian scientist Antônio José Roque da Silva, director of CNPEM and the Sirius project (new Synchrotron Light Lab). Learn more about the plenary sessions, here.

Organization. The chair of the event is Professor Ivan Helmuth Bechtold (Physics Department of UFSC) and the co-chair is Professor Hugo Gallardo (Department of Chemistry of UFSC). The program committee is formed by professors Iêda dos Santos (UFPB), José Antônio Eiras (UFSCar), Marta Rosso Dotto (UFSC) and Mônica Cotta (Unicamp). Get to know all the organizers, here.

Exhibitors and sponsors. 9 companies have already confirmed their participation in the event. Those interested in booking booths or participating with other forms of sponsorship can contact Alexandre at the e-mail comercial@sbpmat.org.br.

News from B-MRS Members

– B-MRS member Prof. Sidney José Lima Ribeiro (UNESP Araraquara) was elected Fellow of the European Academy of Sciences. Know more.

– B-MRS member Prof. Luciana Reyes Pires Kassab (Fatec São Paulo) is co-editor of Elsevier’s new book on photonic nanostructures. Know more.

– B-MRS members Prof. Sérgio Ricardo de Lázaro and Luis Henrique da Silveira Lacerda (UEPG) are authors of a new book on Density Functional Theory. Know more.

Reading Tips

– A Brazilian scientific team obtained the largest sheet of graphene ever reported with a simple and low-cost chemical method. The work is the cover article of the flagship journal of the Royal Society of Chemistry (RSC) and was published in the RSC release (Chemical Science). Know more.

– Scientists are able to film microparticles colliding with metals at high speed and, based on the data obtained, they can predict what can occur with the particle and the material. The study can benefit industrial processes based on the impact of microparticles on surfaces (Nature Communications). Know more.

– When conducting experiments with gold nanoparticles, scientists discover an unexpected way of light – matter interaction, which can help develop optical nanoantennas and nanocomponents (ACS Nano). Know more.

Opportunities

– Postdoctoral positions for glass research at CeRTEV (São Carlos, Brazil). Know more.

Events

Escola de Fabricação e Caracterização de Nanomateriais e Nanodispositivos. Duque de Caxias, RJ (Brazil). February 18 – 22, 2019. Site.

International Workshop on Advanced Magnetic Oxides (IWAMO 2019). Aveiro (Portugal). April 15 – 17, 2019. Site.

2019 E-MRS Spring Meeting e IUMRS – ICAM. Nice (France). May 27 – 31, 2019. Site.

XVIII B-MRS Meeting. Balneário Camboriú, SC (Brazil). September 22 – 26, 2019. Site.

You can suggest news, opportunities, events or reading tips in the materials field to be covered by B-MRS Newsletter. Write to comunicacao@sbpmat.org.br.

New Year Message from B-MRS.

Posted on Wednesday 19 de December de 2018

With this New Year Message, I greet the entire B-MRS community in Brazil and abroad.

There is great expectation that in 2019 Brazil will resume its investments in science, technology and innovation, which we believe to be minimally necessary for the continuation of our system, developed with tremendous effort over the last decades. For the meeting that the academic community had with the future minister of science and technology in early December 2018, the main suggestion B-MRS sent was about reinstating the budget in the area. It is known that Brazil needs to invest much more in the generation of knowledge to solve its serious economic and social problems. Reinstating the budget is merely the first and most urgent step given the situation of universities and research centers in the country. Also important and part of B-MRS ‘s suggestions is the emphasis on partnerships between ministries to address the problems of society at large, which always entail knowledge, technology and innovation, and the search for synergy with the private sector to transform knowledge into wealth and social well-being.

I end by thanking the B-MRS community, wishing all much health and success in 2019, and hoping to meet many of you in our next Meeting at Balneário Camboriú (SC), September 22-26.

Professor Osvaldo Novais de Oliveira Junior

President of B-MRS

B-MRS Member is elected Fellow of the European Academy of Sciences.

Posted on Wednesday 19 de December de 2018

Professor Sidney José Lima Ribeiro (UNESP Araraquara), a member of B-MRS, was elected Fellow of the European Academy of Sciences (EurASc) in December.

EurASc Fellows are elected through a process that consists of a nomination made by a member of the society, who must present curriculum information of the nominee and nomination and support letters, followed by acceptance of the application by the Society’s General Board. After that, the candidate is invited to be a Fellow.

Members of B-MRS are authors of a new book on Density Functional Theory.

Posted on Thursday 13 de December de 2018

Prof Sérgio Ricardo de Lázaro (left) and Luis Henrique da Silveira Lacerda.

The members of B-MRS Sérgio Ricardo de Lázaro (UEPG professor) and Luis Henrique da Silveira Lacerda (PhD student at UEL/UEPG/UNICENTRO) are the authors of the book “Teoria do Funcional da Densidade e Propriedades dos Materiais“, published by the Brazilian publishing house CRV. The book is co-authored by Renan Augusto Pontes Ribeiro, also a doctoral student of the program. The Density Functional Theory (DFT) is based on Quantum Mechanics and was applied in the area of Materials Chemistry.

More information about the book: https://editoracrv.com.br/produtos/detalhes/33536-crv

B-MRS Member is editor of Elsevier’s new book on photonic nanostructures.

Posted on Wednesday 12 de December de 2018

Professor Luciana Reyes Pires Kassab (School of Technology of São Paulo, Fatec São Paulo), member of B-MRS, is co-editor of the book “Metal Nanostructures for Photonics”. Published by the Elsevier publishing house, the book discusses the photonic properties and applications of metallic nanostructures, as well as the preparation and characterization techniques of these materials. Professor Luciana R. Pires Kassab edited the book with Professor Cid Bartolomeu de Araujo (UFPE). More than 40 authors from different countries sign the book’s 12 chapters.

More information about the book: https://www.elsevier.com/books/metal-nanostructures-for-photonics/pires-kassab/978-0-08-102378-5

B-MRS Newsletter. Year 5, issue 11.

Posted on Friday 30 de November de 2018

If you cannot see this newsletter properly, see it here

Newsletter of the
Brazilian Materials
Research Society

Year 5, issue 11. December 7, 2018.

Featured Paper

Experiments carried out with quantum dots by Brazilian scientists revealed a situation in the energy band structure of these nanoparticles that had never before been observed in any material. The study was reported in Nano Letters. Know more.

Featured Scientist

We interviewed Heinz von Seggern, Professor at TU Darmstadt and former researcher at Bell Labs and Siemens. This distinguished German scientist, whose contributions range from fundamental research to invention of devices, has a history of interactions with the Brazilian materials community, including the pioneer Bernhard Gross. Know more.

News from B-MRS Members

Prof. Valmor Roberto Mastelaro (IFSC-USP) took over as editor of the Journal of Alloys and Compounds. Know more.
Founding member Prof. Fernando Galembeck (Unicamp) wins national award in the area of Nanotechnology. Know more.

XVIII B-MRS Meeting/ Encontro da SBPMat
(Balneário Camboriú, SC, Brazil, September 22 – 26, 2019)

Symposia. A large number of proposals was received. The list of approved symposia will be announced shortly.

Abstract submission. The important dates will be announced shortly.

Plenary speakers and Memorial Lecture. Find out what the plenary talks of the event will be and who will deliver the traditional Joaquim da Costa Ribeiro Memorial Lecture. See here.

Organization. The meeting chair is Prof. Ivan Helmuth Bechtold (Department of Physics, UFSC) and the co-chair is Prof. Hugo Gallardo (Department of Chemistry, UFSC).

Exhibitors and sponsors. Companies interested in participating in the event with booths or sponsoring can contact Alexandre at comercial@sbpmat.org.br.

Reading tips

After understanding the relationship between microstructure and properties in superalloy, scientists apply treatment that leaves this material even stronger and resistant at high temperatures, allowing its use in electric generators and nuclear reactors (Science Advances). Know more.
Scientists find experimental evidence that two-dimensional CrI3 material can behave as a magnetic topological insulator without having an external magnetic field, and point to the possibility of using the material in spintronics (Physical Review X). Know more.
Inspired by plant leaves, a polymer with a micro-channel network through which fluids circulate regulates its own temperature and generates thermoelectric energy, promising applications in health, civil construction, aerospace industry and more (Scientific Reports). Know more.
Scientists develop a transmission electron microscopy tool to study the interaction of light and matter in individual particles at the nano scale in real time and at very high resolution (Scientific Reports). Know more.

Opportunities

Postdoctoral fellowship in Condensed Matter Physics at the Federal University of ABC (SP, Brazil). Know more.
Postdoctoral fellowship at USP (SP, Brazil). Know more.

Events

VII Curso de Análise de Minerais/Minérios pelas Técnicas de DRX e FRX. Fortaleza, CE (Brazil). December 10 – 14, 2018. Site.
International Workshop on Advanced Magnetic Oxides (IWAMO 2019). Aveiro (Portugal). April 15 – 17, 2019. Site.
2019 E-MRS Spring Meeting e IUMRS – ICAM. Nice (France). May 27 – 31, 2019. Site.

You can suggest news, opportunities, events or reading tips in the Materials field to be covered by B-MRS Newsletter. Write to comunicacao@sbpmat.org.br.

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Featured scientist: Prof. Heinz von Seggern (TU Darmstadt).

Posted on Friday 30 de November de 2018

In the late 1970s, when he was a doctoral student, German scientist Heinz von Seggern came to Brazil for the first time and met some local researchers with whom he still collaborates. His host was Bernhard Gross, another German scientist who settled in Brazil and is considered a pioneer of materials research in the country. This was the beginning of a series of scientific visits of Heinz von Seggern to Brazil, which included the participation in five B-MRS Meetings, the annual events of the Brazilian Materials Research Society. In the last edition of the event, Prof. Heinz von Seggern gave a plenary lecture on ferroelectrets.

Heinz von Seggern graduated in physics from the University of Hannover (Germany) in 1976. He received his PhD degree in electrical engineering from the Technical University of Darmstadt (Germany) in 1979. His thesis advisor was Prof. Gerhard Sessler, one of the inventors of the electret microphone, the most common type of microphone in use today. After that, Heinz von Seggern became a postdoc and then a principal investigator at AT&T Bell Laboratories (USA). From 1985 to 1997 he worked at Siemens research center in Erlangen (Germany), starting as a principal investigator and then being promoted to department head. Since 1997, he is Full Professor at the Technical University of Darmstadt, where he leads the Electronic Materials Group.

Throughout four decades of scientific research, Heinz von Seggern has made important contributions to the field of materials in understanding fundamental phenomena, developing analysis techniques and applications, and inventing devices. He has published over 280 scientific papers in peer-reviewed journals with more than 7.800 citations, and his h-index is 46 (Google Scholar).

See our interview with this scientist.

B-MRS Newsletter: – What motivated you to become a scientist and, particularly, a materials scientist?

Heinz von Seggern: – Already as a high school student my main interest was directed towards natural science. This passion was strongly motivated by one of my teachers who really understood to ignite my love for this field. So it was a natural thing for me to study physics, however, I always kept in touch with mathematics and chemistry. After finishing my diploma in physics at the Technical University of Hannover, I started my PhD work at the Technical University of Darmstadt in the electrical engineering department and two and a half years later I received my doctoral degree in electrical engineering. The following four out of five years I spend at Bell Laboratories in Murray Hill, New Jersey, USA whose fabulous working conditions made my bonds to science even stronger. My path to materials science started with my return to the Corporate Research Laboratories of Siemens AG in Erlangen where I spend 12 years before being appointed as full professor at the Technical University of Darmstadt, Germany. In the time at Siemens my work was focused on more practical aspects of science which I started to be increasingly interested in. The ability to change and adapt material properties to practical demands, which is the basic task of materials science, fascinated me more and more.

B-MRS Newsletter: – In your opinion, what are your main contributions to the materials field? Please, select a couple of discoveries/developments, describe them briefly, describe the context in which they were developed, and share the papers or patents references.

Heinz von Seggern: – Since I have been working on different subjects it is not so easy to point out my or our major contributions to the materials field. I will concentrate on one discovery or development in each field. Let’s start with my PhD study. My task was to understand the charge transport and electronic trap structure of Teflon FEP thin films to back up the lifetime expectation of electret microphones. I discovered by means of thermally stimulated discharge measurements that Teflon FEP contains two different types of energetically deep electron traps which are located near the surface and in the bulk of the films, respectively. This discovery was made possible by comparing TSD results of corona and electron beam charged samples whereby corona charging leads to filling of traps close to the surface and electron-beam charging allowed for deposition of charge into surface and bulk traps dependent on the utilized electron energy. From this finding a charge transport model was developed depending on the initial location of the electrons after charging. The model is based on trapping and thermally induced release. In case of corona charging the transport is initiated by a thermally induced release of electrons from surface traps and a subsequent capture and release by deeper bulk traps [Ref: H. von Seggern, J. Appl. Phys. 50, 7039 (1979), Heinz von Seggern, J. Appl. Phys. 50, 2817 (1979)]. The morphological reason for the different trap depth of surface and bulk can be seen in the film production process where different cooling rates apply to the surface and the bulk of the films.

After finishing my PhD degree I continued this research at Bell Laboratories investigating the transport of positive charges. In contrast to the electron traps, hole traps are relatively shallow and are distributed through the complete film. Once filled they empty relatively fast already at room temperature. On the other hand the number to energetically deep traps was found to be rather small resulting in a low capture rate. This implies that holes have a high probability to penetrate the film via hopping through shallow traps without being captured by deep traps which implies a rather low charge stability of Teflon FEP for holes. We were able to show that this problem can be circumvented by charging at high temperatures filling only deep traps [H. von Seggern, J. West, J. Appl. Phys. 55, 2754 (1984)]. This charge stabilization for positive charges recently became important with respect to so called piezoelectrets where by symmetry breaking a novel piezoelectric material was generated utilizing only nonpolar components. For these devices the stability of both charge types is essential.

During my time at the Corporate Research Labs of Siemens AG in Erlangen the field of interest changed to x-ray storage phosphors which are currently applied in so called image plates used commercially in x-ray diagnostics. The image plate thereby combines the classically utilized silver halide film and the intensifying screen where latter was applied to convert incoming x-rays to visible photons which are then detected by the photographic silver halide film. The working principle of the image plate is that by x-ray exposure electrons and holes are generated and trapped as F-centers and V_k-centers, respectively. Readout occurs by photostimulation of the electron and radiative recombination with the V_k-center. The released energy is then converted to a rare earth ion which emits light at its characteristic wavelength. Thereby the intensity of the emitted photons is indicative for the locally absorbed x-ray dose. My major contribution to this field was the discovery of the basic working principle of these photostimulable phosphors and the existence of spatially correlated and uncorrelated PSL centers which allowed for a deeper insight into the physics of storage phosphors [H. von Seggern et al., J. Appl. Phys. 64, 1405 (1988)]. Another contribution was the invention of neutron image plates fabricated by mixing an effective neutron absorber to the granular storage phosphor particles [T. Bücherl, H. von Seggern et al., Nucl. Instr. Meth. A333, 502 (1993)]. This technique is still widely used in neutron image detection.

After accepting the position as full professor in Materials Science at the Technische Universität Darmstadt I concentrated my efforts on the field of Organic Electronics which I already started at Siemens some years before. In the first years we focused on the energetic trap distribution of organic semiconductors. We were the first to experimentally prove the existence of a Gaussian trap distribution predicted earlier by Bässler et al. through Monte Carlo simulation. The experimental method used a refined thermally stimulated discharge technique known as fractional discharge, where a stepwise increase in temperature combined with the corresponding thermal release of charge allows one to determine the trap distribution which up to now is the only technique known to directly determine the distribution of traps [N. von Malm et al., J. Appl. Phys. 89, 5559 (2001); R. Schmechel et al., Phys. Stat. Sol. (a) 201, 1215 (2004)].The largest scientific attention we received, however, for the invention of the organic light emitting transistor (OFET) based on tetracene and a polyfluorene derivative. In such OFETs it was shown to be possible to obtain ambipolar transport by injection of electrons and holes from source and drain, respectively [A. Hepp, H.von Seggern et al., Phys. Rev. Let. 157406, 1 (2003); M. Ahles, H. von Seggern et al., Appl. Phys. Let. 84, 428 (2004)]. It was also shown that the same ambipolar transport can be used to construct colour tunable OFETs [E. J. Feldmeier, H. von Seggern et al., Adv. Mater 22, 3568 (2010)] where the motion of the emissive recombination zone through the transistor channel is used to excite different overlaying organic semiconductors with different emission wavelength.

In the last years at TU Darmstadt I have revisited charge storage in organic polymers known as ferro- or piezoelectrets. The cellular polymer polypropylene has shown by Finnish scientists to exhibit large piezoelectric d₃₃ coefficients after poling by high electric fields with the only disadvantage that the trapped charge turned out to be thermally unstable. Therefore structures changed quickly to Teflon based sandwiches of solid FEP /ePTFE/ solid FEP, where ePTFE is a highly porous PTFE consisting of up to 98% air, and later to completely air filled structures. My contribution to that field is the physics explaining the hysteresis and thereof the deduction of the maximal stable polarization which then allows for the theoretical deduction of the piezoelectric d₃₃ coefficient for plane-parallel structures. This knowledge allows for the optimization of the piezoelectric effect and therewith increases the potential for future applications [S. Zhukov, H. von Seggern et al., J. Appl. Phys. 102, 044109 (2007); S. Zhukov, H. von Seggern et al., Scientific reports 8, 4597 (2018)].

B-MRS Newsletter: – Please make a brief story of your interaction with Brazil and with Prof Bernhard Gross.

Heinz von Seggern: – During my PhD work at TU Darmstadt Prof. Gross was a frequent guest of Prof. G.M. Sessler, my thesis adviser. Before my final PhD defense he invited me to visit the Institute of Physics of the University of Sao Paulo (USP) in Sao Carlos. Here I met all the people with whom I am still in contact and friendship with, namely Roberto M. Faria and Jose A. Giacometti who in the meantime have become established professors at USP. After finishing my PhD study I went to Bell Laboratories, Murray Hill, NJ. where Profs. Gross and Sessler were welcomed guest almost every year. The collaboration was extremely fruitful and resulted in a number of joint publications. In 1984 I then left Bell Labs and started to work at Siemens Corporate Research on different topics for the next 12 years and naturally the collaboration was at rest. But as soon as I became appointed Professor at TU Darmstadt I revitalized my connection to the Institute of Physics of Sao Carlos, whose polymer group is now called Grupo de Polimeros “Prof. Bernhard Gross”. From that year on I visited initially Prof. Giacometti and later Prof. Faria almost yearly for up to two month financed generously by FAPESP through various programs. These stays were always very enjoyable and busy, and quite a few publications have resulted.

B-MRS Newsletter: – How many times did you attend the B-MRS Meetings? Do you remember when was the first time?

Heinz von Seggern: – In total I have attended five Brazilian MRS meetings starting in Natal 2007, Florianopolis 2012, Joan Pessoa 2014, Rio de Janeiro 2015 and again Natal in 2017. My first stay in Natal 2007 I remember especially since I was allowed to present our work in front of a great audience on the recently discovered light emitting organic field effect transistor and, on a more personal note, I also remember the wonderful Caipirinha my wife and me were enjoying every evening during sunset at the ocean side.

B-MRS Newsletter: – You have about 40 years of strong experience as a researcher. Please leave a short message with some advice for the students and junior scientists of our community.

Heinz von Seggern: – In the context of scientific education Prof. Bernhard Gross once said to me: “For someone who knows nothing, everything is possible.” There is a lot of truth in these few words. We all tend to sometimes talk about things that seem to be obvious to us but in reality they are not. My advice therefore is, especially to young scientists, to always ask yourself whether you understand the physical and/or chemical grounds of your current research. If not I suggest to you to acquire the missing basics, which then allows you to select from “everything is possible” the physical meaningful trials. This will definitely help you to make the right decisions to continue your research in a meaningful way.