B-MRS members are co-authors of an article that is among the most read 100 papers of Scientific Reports in 2018 in the area of materials.

Prof Elson Longo
Prof Elson Longo

Professor Elson Longo (CDMF-UFSCar), founding member and former president of B-MRS, is the corresponding author of an article that appears in the Top 100 2018 ranking of the journal Scientific Reports in the area of Materials Science. The ranking highlights the most read articles in 2018, among those published that year in the journal of the Nature group. The paper was published on January 30, 2018 and received 1,042 views throughout the year.

Entitled Towards the scale-up of the formation of nanoparticles on alpha-Ag2WO4 with bactericidal properties by femtosecond laser irradiation, the article is signed by eleven authors, six of them from Brazilian institutions, including the researcher Camila Cristina de Foggi (UNESP), who is also a B-MRS member.

The work proposes a new process to produce bactericidal nanocomposites based on silver nanoparticles and semiconductor materials. The method increases 32 times the bactericidal action of the nanocomposite and, at the same time, generates a new class of spherical nanoparticles.

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B-MRS Newsletter. Year 6, issue 3.


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Newsletter of the
Brazilian Materials
Research Society

Year 6, issue 3. April 8, 2019.

B-MRS News

XVIII B-MRS Meeting. Abstracts must be submitted by April 15. See the message of the event coordinators, directed to the entire scientific community. Here.

University Chapters Program. Student teams from UFMS and UNIFESP São José dos Campos have joined this B-MRS program, which is now present in the 5 regions of Brazil. Know more.

Elections for Board of Directors and Council. B-MRS presents the electoral commission, which is conducting the process. Know more.

Featured Paper

A team of researchers from Brazilian universities developed a film that simultaneously releases two antibacterial and anticancer active ingredients. The material demonstrated efficiency, in vitro, in the elimination of bacteria and cancer cells. The film has potential to be used in the topical treatment of infectious lesions and malignant tumors. The work was reported in ACS Applied Materials and Interfaces. Know more.

figura news

Featured Scientist

This month our interview is with the scientist who led the introduction and development in Brazil of structural and molecular crystallography by X-rays – now widely used in our community. In that field, she founded the first laboratory and a scientific society. She also formed several generations of structural crystallographers distributed throughout the country, and also collaborated with dozens of scientists from various areas and countries to unravel the structure of materials and molecules. We are referring to Yvonne Primerano Mascarenhas (USP), who will be honored by B-MRS in the XVIII B-MRS Meeting. Know more.

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News from B-MRS Members

– B-MRS member Aldo J. G. Zarbin (UFPR) wrote about the future of Chemistry in Nature Chemistry at the invitation of the journal. Know more.

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

Website: www.sbpmat.org.br/18encontro/

Deadline for abstract submission: April 15th.

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. See instructions for authors, here.

Symposia. 23 symposia proposed by the international scientific community compose this edition of the event. See the symposia list, here.

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, aqui.

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.

Venue of the opening session. The Opening Ceremony, the Memorial Lecture and the Cocktail will be held in the Cristo Luz Complex. More information, here.

Memorial Lecture. The traditional Memorial Lecture Joaquim da Costa Ribeiro will be given by Professor Yvonne Primerano Mascarenhas (IFSC – USP). Know more about the speaker.

Plenary lectures. Leading scientists from institutions in Germany, Italy, Spain and the United States will deliver plenary talks on cutting-edge 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. 37 companies have already confirmed their participation in the event. Those interested in sponsoring/support can contact Alexandre at the e-mail comercial@sbpmat.org.br.

Reading Tips

– Using advanced experimental technique and simulations, scientists reveal details of how crystal formation occurs, layer by layer, at the atomic level. Study contributes to the development of high quality materials (Nature Physics). Know more.

– Scientists were able to produce nanostructures of crystalline metals using nanomolds. In addition to overcoming experimental challenges and creating simple techniques, they explained the mechanisms involved in this nanomodeling (Physical Review Letters). Know more.

– Research led by Brazilian scientists contributes to the development of very stable ceramic photocatalysts needed to produce alternative fuels from CO2 and artificial photosynthesis. The study was highlighted by The American Ceramic Society (The Journal of Physical Chemistry C). Know more.

Innovation. Partnership between Brazilian nanotechnology company and textile industries will soon bring to the market new functional fabrics that protect against heat, UV rays and insects, as well as prevent odors. Know more.


– Post-doctoral Fellowship in Physical Chemistry of Colloids. Know more.

Mexican Materials Societies call for symposia proposals for the XXIX IMRC that will be held in August 2020 in Cancun (Mexico). Know more.


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

I Simpósio de Pesquisa e Inovação em Materiais Funcionais. São Carlos, SP (Brazil). May 23 – 24, 2019. Site.

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

20th International Symposium on Intercalation Compounds (ISIC). Campinas, SP (Brazil). June 2 – 6, 2019. Site.

10th International Conference on Materials for Advanced Technologies (ICMAT 2019). Singapore. June 23 – 28, 2019. Site.

X Método Rietveld. Fortaleza, CE (Brazil). July 8 – 12, 2019. Site.

20th International Sol-Gel Conference. Saint Petersburg (Russia). August 25 – 30, 2019. Site.

21st Materials Research Society of Serbia Annual Conference (YUCOMAT 2019) and 11th IISS World Round Table Conference on Sintering (WRTCS 2019). Herceg Novi (Montenegro). 2 a 6 de setembro de 2019. Site.

XVIII B-MRS Meeting. Balneário Camboriú, SC (Brasil). 22 a 26 de setembro de 2019. Site.

19th Brazilian Workshop on Semiconductor Physics. Fortaleza, CE (Brasil). 18 a 22 de novembro de 2019. Site.

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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.

B-MRS presents the Electoral Commission for 2019 elections.

B-MRS Electoral Comission 2019: from the left, Cícero Cena da Silva, Laura Péres and Marco Cremona.
B-MRS Electoral Comission 2019: from the left, Cícero Cena da Silva, Laura Péres and Marco Cremona.

B-MRS  is pleased to present the committee responsible for organizing the process that at the end of this year will conclude with the election of the next Executive Board and members of the Council of the society. All active members with paid 2019 annuity will be eligible and may vote.

The members of the Electoral Commission are:

  • Prof. Cícero Rafael Cena da Silva (UFMS) .
  • Prof. Laura O. Péres (UNIFESP)
  • Prof. Marco Cremona (PUC-Rio)

The commission will soon be making available the election calendar and other information on the B-MRS  website. The information will be disclosed in B-MRS’s e-newsletter and social media, as well as sent by e-mail to the active members.

The current Executive Board of B-MRS thanks the participation of Professors Cena, Cremona and Péres in the organization of this important process of the Society.

Two more universities participate in B-MRS University Chapters program.

Members and supervisor of the UFMS UC.
Members and supervisor of the UFMS UC.

As of March, with the incorporation of a University Chapter (UC) unit at the Federal University of Mato Grosso do Sul (UFMS), Brazil’s five regions are present in the map of the B-MRS’s UCs. In addition, the map of the program gains a new spot in the state of São Paulo, through the participation of a team in the Federal University of São Paulo (UNIFESP), campus of São José dos Campos.

The UCs program, which now has 11 units, brings together undergraduate and graduate student teams from Brazilian universities around complementary activities for academic education.

According to the president of UFMS UC, Gustavo Sander Larios, M.S., the creation of the UC was motivated by the desire to increase interaction among students from different laboratories, departments and research groups. Thus, the team, which is made up of undergraduate, masters and PhD students from the areas of Materials Science, Physics and Chemistry, will stimulate the organization of seminars and scientific meetings involving members of the UC and researchers from B-MRS. “We intend to promote activities that stimulate the development of scientific knowledge, given the national and international research trends, provided through the interaction among the UC members,”adds Larios. The supervisor of this unit is Professor Cícero Rafael Cena da Silva.

Members and supervisor of the UC unit at UNIFESP - São José dos Campos.
Members and supervisor of the UC unit at UNIFESP – São José dos Campos.

At the UC of the University of São José dos Campos, UNIFESP, the main objective is to disseminate Materials Engineering and Science among university students from all over the Vale do Paraíba region and also in society as a whole, says the master’s Verônica Ribeiro dos Santos, president of the unit, and Professor Manuel Henrique Lente, the supervisor of the UC. The team intends to “divulge the concept of Materials Engineering, since for many it is still unknown, given the great diversity of areas of expertise that the professional in this field is capable of carrying out.” According to Verônica Ribeiro dos Santos and professor Manuel Henrique Lente, the group aspires, in the future, to make their UC an extracurricular source of scientific and technological knowledge and to increase the number of members. Some of the activities the team intends to promote are: seminar cycles involving students and researchers from UNIFESP and other institutions; lectures by representatives of S&T support agencies, class entities, industrial sectors, etc.; technical visits to R&D institutes, companies and incubators; summer courses; dissemination lectures in high schools. In order to carry out the activities, the UC has a comprehensive team of 24 undergraduate students (Bachelor’s degree in Science and Technology, and Materials Engineering), three master’s and one doctoral students (Post-graduation in Materials Science and Engineering, PPGECM), all from UNIFESP.

Get to know B-MRS’s UCs Program and the eleven units it has so far in the states of Mato Grosso do Sul, Minas Gerais, Pará, Pernambuco, Piauí, Rio Grande do Sul and São Paulo: https://www.sbpmat.org.br/en/university-chapters/ucs-da-sbpmat/

New University Chapter established at UFPE.

UC at UFPE: tutor, board of directors (students) and some members of the unit.
UC at UFPE: tutor, board of directors (students) and some members of the unit.

The University Chapters (UCs) program of B-MRS  begins 2019 with a new member, the UC of the Brazilian Federal University of Pernambuco (UFPE). With the creation of this unit, the program will have nine UCs distributed in the south, southeast, northeast and north of the country.

The interdisciplinary team of the new UC brings together 15 students (three undergraduate, five masters and seven doctoral students) from courses in Chemistry, Biological Sciences and Materials Science at UFPE. The tutor of the unit is Professor Petrus d’Amorim Santa Cruz Oliveira.

“What motivated us to create our UC was the need to explore the world of Materials Science, reinventing new ways to broaden and bring people from all parts, thus diversifying and strengthening our education more and more,” says Karolyne Santos da Silva, president of the UC. “Our highest expectation is to awaken young people to science, showing that there are possibilities to be innovative and have the opportunity to undergo new experiences with other researchers,” adds the doctoral student in Materials Science.

In the context of B-MRS’s UCs program, the team initially plans to hold a series of events: a holiday course, the 1st Meeting of Materials Science and Engineering of Pernambuco and annual workshops.

Get to know B-MRS’s UCs Program and the nine units it has so far in the states of Minas Gerais, Pará, Pernambuco, Piauí, Rio Grande do Sul and São Paulo: https://www.sbpmat.org.br/en/university-chapters/

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

Prof. Oswaldo Luiz Alves
Prof. Oswaldo Luiz Alves

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.

New Year Message from B-MRS.

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.

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

ano novo sbpmat

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

Prof Sérgio Ricardo de Lázaro (left) and Luis Henrique da Silveira Lacerda.
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 Newsletter. Year 5, issue 11.


If you cannot see this newsletter properly, see it here

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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.

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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.

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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.


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

  • Postdoctoral fellowship at USP (SP, Brazil). Know more.


  • 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.

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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).

Prof. Heinz von Seggern.
Prof. Heinz von Seggern.

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 Vk-centers, respectively. Readout occurs by photostimulation of the electron and radiative recombination with the Vk-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.