Featured scientist: Edson Roberto Leite.

Prof Edson Roberto Leite
Prof Edson Roberto Leite

Edson Roberto Leite memories related to science are all very pleasant: the book about rockets in his childhood in the interior of São Paulo, the opportunity to use an exceptional microscope during the sabbatical period in the United States, the discovery of a mechanism for the growth of nanocrystals at the Brazilian National Synchrotron Light Laboratory…

Some of these wonderful memories include the many occasions experienced alongside his tutor and scientific father, Professor José Arana Varela, a prominent Brazilian materials scientist who died in 2016. Arana Varela was honored by B-MRS with the creation, in 2019, of an award that bears his name, and which annually distinguishes a prominent researcher from Brazil, who gives a plenary lecture at the Society’s annual event. In its first edition, the award was befittingly granted to Edson Roberto Leite, professor at the Federal University of São Carlos (UFSCar) and scientific director of the Brazilian National Nanotechnology Laboratory (LNNano-CNPEM). Leite is also editor for Latin America of the Journal of Nanoparticle Research (Springer).

Edson Roberto Leite received his first degree in Materials Engineering from UFSCar in 1988. In doubt between pursuing a career in industry or academia, he initially tried to reconcile both. After graduating, he worked in the research and development area at 3M, while doing his master’s degree and starting his doctorate, both in Materials Science and Engineering at UFSCar. In 1992, he left the company in order to dedicate his time to the doctorate, a decision that he recalls did not please his father-in-law, who was concerned with the livelihood of the family that by now included two children. However, over the years, the results of this decision have been very positive. In 1994, shortly after defending his doctorate, Leite became a professor in the Chemistry Department at UFSCar and started a career as a researcher in materials, which would not only be fruitful, but also enjoyable.

Co-author of more than 400 scientific articles published with more than 19 thousand citations, today Leite has an h index of 72 (Google Scholar). The scientist is also the editor of three books related to materials for energy and co-author of a book on the process of nucleation and growth of nanocrystals. Leite received several awards, including the Scopus Prize from Elsevier/CAPES (2006), for the excellence of his scientific production as a whole, and the John Simon Guggenheim Memorial Foundation Fellowship (2009), awarded to scientists with exceptional research skills. In 2012, Edson Leite was elected member of the World Academy of Ceramics and the Academy of Sciences of the State of São Paulo. In 2014, he was cochair of the Spring Meeting of Materials Research Society, held in San Frascisco (USA). In 2019 he was elected full member of the Brazilian Academy of Sciences (ABC).

Read our interview and learn more about this scientist, his main contributions and his memories of Professor Arana Varela.

B-MRS newsletter: At school, you had more affinity with science subjects, right? Do you remember how this taste for science originated?

Edson Roberto Leite: A person’s story always has the personal version and the version of the people who interacted with him. I will recount my perspective of how it happened.

At school I always had a strong affinity for Science and History. A striking memory was when I was in the third grade of elementary school and my father took me to the Municipal Library of Araras to take out a membership card so I could access books. The first book I chose was about rockets. I have always loved the conquest of space and the science behind fundamental historical moments. It is noteworthy that man had reached the moon only a few years earlier, nuclear power was seen as the global energy solution and semiconductors were just beginning.

In addition to this fond memory, there were other motivations, including Jonny Quest, a really cool cartoon. This animation, in addition to the adventures, had a lot of science fiction, and Jonny’s father (Dr. Benton Quest) was a renowned scientist with an excellent research laboratory in his own home.

My childhood, then, was always marked by a strong influence of science classes. I think it easily guided me to choose Engineering. At first the idea was to become a mechanical engineer, but during my prep course for the entrance exam I was introduced to Materials Engineering, at UFSCar. I took the exam in the middle of 1983 and passed. From then on I knew what I wanted and what I liked.

However, there was still a doubt, whether to go to the academic area or go to industry (my father was a Nestlé employee in Araras and the industrial sector always caught my attention). During my undergraduate studies, I went to live at the student housing headed by Celso V. Santilli (today an important researcher in the field of Materials, Professor at IQ-UNESP-Araraquara) and he helped me to participate in an undergraduate research program with professors Elson Longo and José Arana Varela. That was when I learned what science was and that increased my taste for the academic area. In 1984, I had the first undergraduate scholarship from FAPESP under the guidance of Professor Varela (who was a visiting professor in the Materials Engineering department (DEMa) at UFSCar). In 1988 I graduated, joined the DEMa-UFSCar master’s degree program and went to work as a development engineer at 3M do Brasil, in Sumaré, SP. My director at 3M was the engineer Aloysio Pizarro and he released me for the master’s degree (which I defended in 1990 under the guidance of Professor Elson) and for the doctorate (in 1990). In 1992, I realized it would be impossible to reconcile the research area and my activities at 3M, so I left 3M to focus entirely on my academic research, returning to São Carlos. I finished my doctorate in 1993 under the supervision of Professor José A. Varela. In January 1994, I became an adjunct professor in the Chemistry department at UFSCar and joined LIEC (Interdisciplinary Laboratory of Electrochemistry and Ceramics), founded by Elson, Varela and Bulhões (Professor Luís Otávio S. Bulhões). I went back to the place that had introduced me to science.

Those moments influenced me…

B-MRS newsletter: In your assessment, what are your main contributions to the Materials area?

Edson Roberto Leite: Ever since undergraduate research, I have been working mainly with inorganic materials, more specifically with ceramic materials. So, I will report the contributions I believe are most important, according to my point of view (in fact these may be the contributions I most enjoyed working with).

Since 1994 I have been working with chemical and physical-chemical materials and have been involved in several areas, among them: chemical synthesis of ceramic oxides, synthesis of nanoparticles with controlled size and morphology, growth of nanocrystals, electrical properties of ceramic oxides, materials for application in alternative energy devices and transmission electron microscopy (TEM). During this period, always developing works in collaboration with professors Elson Longo and José A. Varela, at LIEC of DQ-UFSCar. Among these different areas I will highlight my contributions to the growth of nanocrystals and the work on alternative energy.

In 1998, that is, 4 years after I was hired, I went on a sabbatical in the USA, in the group of Professor Martin P. Harmer, at Lehigh University (Betlehem, PA). In my sabbatical, I worked on converting polycrystalline ceramics into monocrystalline ceramics, using controlled grain growth. It was a wonderful year and my recollection of that period is vivid in my memory. I still remember the smell of the laboratory and the friendships I cultivated. From a professional point of view, the work drew my attention to the process of solid-state crystal growth. My contribution to the project was to characterize the growth process using advanced transmission electron microscopy techniques. At that time I had the opportunity to operate the VG-603 analytical transmission electron microscope. There were few microscopes like this being produced, and I still remember the words of the coordinator of the Lehigh microscopy laboratory, Dr. Dave Ackland saying that “few researchers in the world have had the honor of operating this equipment.” Returning to Brazil in 1999, I dedicated a lot of my time to microscopy and, with the help of the newly created Electronic Microscopy Laboratory of LNLS (created in 1997 by Dr. Daniel Ugarte), I began studying the process of growing nanocrystals in colloidal solution. I quickly identified, for SnO2 nanocrystals, a growth mechanism recently described in the literature known as “Oriented Attachment” (OA). The first article we published about this nanocrystal growth mechanism was in 2003. During this period I created a group of high-level master and doctoral students (today these students are researchers and professors), which truly allowed exploring this growth mechanism. In fact, we published, almost simultaneously with American groups, the first kinetic model to describe this growth process, and shortly afterwards we published two important articles, one related to the growth of anisotropic nanocrystals and the other correlating the OA process with a polymerization process. Both articles are considered pioneers in the area. International recognition in the area came with the invitation to publish two review articles (one at Nanoscale and the other at CrysEngComm), one of them in collaboration with leading international experts in the field of nanocrystal growth kinetics by OA.

I started working in alternative energy in 2004, when I helped organize a symposium on the theme at the MRS Spring Meeting in San Francisco. After that, we invested in this area and, with a new group of brilliant students, we achieved fantastic results, between 2007 and 2016, regarding the development of hematite photo anodes to promote water photo-electrolysis aimed at hydrogen production. We developed an electrode manufacturing process based on colloidal nanocrystal deposition. This enabled the highest impact publications of my career, in journals such as JACS and Energy Environ. Sci. In the same period we developed a method for synthesizing MoS2 (2D material), combining non-hydrolytic sol-gel method and microwave reaction. This again resulted in excellent materials for electrocatalysis and for supercapacitors. This research also enabled publications in high-impact journals, such as Chem. Comm and Advanced Energy Materials. Without a doubt, this team of students placed us in the state-of-the-art to develop materials for alternative energy.

I would like to highlight just one more important contribution, which was in the study of the combustion process in glass-melting furnaces, carried out with funding from White Martins/Praxair. In this work, carried out with Professor Carlos Paskocimas (currently at UFRN) and Professors Elson and Varela, we characterized the corrosion rate of the furnaces and proposed technological solutions to inhibit this corrosion. This work was a success at the time and we were invited to present the results at Corning Glass and Praxair in the United States.

B-MRS newsletter: You were celebrated in the first edition of the B-MRS José Arana Varela award, which honors this prominent Brazilian scientist (who died in 2016), former president of B-MRS. Professor Varela was your doctoral advisor and co-author of many published articles. Could you share with us some memories about Professor Varela and comment on the scientific partnership both of you developed over time? Feel free to leave any more personal comments.

Edson Roberto Leite: As I mentioned above, I was introduced to Professors Varela and Elson during my undergraduate years, and Professor Varela was my undergraduate and PhD advisor. In fact, I was Varela’s first doctoral student, in 1993. Being the first to win this award is an honor, which made me very happy. Besides being my advisor, Professor Varela was a tutor and almost a father, teaching me and introducing me to the national and international scientific community. It was with him that I made my first trip abroad, in 1993, where he introduced me to the great names of international Ceramics at the American Congress of The American Ceramic Society. It was at this opportunity that I met Professor Gary Messing and Professor Harmer. I remember him introducing me to the famous Professor W.D. Kingery, the father of modern Ceramics. It was Varela who encouraged me to be a member of World Academy of Ceramics. There were several trips, opening new work fronts and new research areas. As a tutor and advisor he knew how to get my attention and point out my mistakes. I remember, more recently, at an MRS Fall meeting in Boston (USA), a long discussion that we had where he, without hesitation, “pulled my ear” and helped me handle future problems I would face as a group leader in the Materials Chemistry area. I know he saw me as a rebellious student, but I’m sure he was proud of the training he gave me. His premature death took me by surprise and I miss him very much. I miss our discussions, our conversations and especially his advice and guidance.

B-MRS newsletter: Please leave a message for our younger readers who are starting a scientific career or are evaluating this possibility.

Edson Roberto Leite: I am not good with words, my students and former students know that I am very direct. I never worried about planning my career, everything was happening as I followed my instincts. What I am today is largely due to my students and the support of two scientific parents, professors Elson and Varela. My job is not a job, it is a hobby. So my message is: To achieve success in a scientific career you must really like what you do.

History of Materials Research: 30 years of LIEC – UFSCar.

The Interdisciplinary Laboratory of Electrochemistry and Ceramics (LIEC) of the Federal University of São Carlos (UFSCar) is completing 30 years of scientific research, development of innovative products and processes, training of scientists and extension activities.

The idea of creating an interdisciplinary laboratory emerged in 1988, from discussions of three research professors, two from UFSCar and the third from UNESP – Araraquara, with education background in chemistry, physics and physical chemistry. These professors were Elson Longo da Silva, Luís Otávio de Sousa Bulhões and José Arana Varela (deceased in 2016). “The idea came about because we had obtained equipment from funding agencies, but there was not enough space in our respective departments to allocate them,” recounted Elson Longo, now professor emeritus of UFSCar, during the commemoration of the anniversary of LIEC, on March 23.

The idea was materialized thanks to a partnership with Companhia Brasileira de Metais e Metalurgia (CBMM) to finance the construction of the building that would house the equipment. The company, Longo said, was interested in the future laboratory developing some products. “Fortunately, we secured their support for the construction of the building at UFSCar,” explained Longo

Soon after, the laboratory began to receive students interested in participating in the research. The first ones, recalls Longo, were Edson Roberto Leite (now professor at UFSCar), Carlos Alberto Paskocimas (currently at UFRN) Ernesto Chaves Pereira (UFSCar) and Maria Aparecida Zaghete (UNESP). “It can be said that over the past 30 years there have been hundreds of students who have completed their studies at LIEC,” said Longo. In addition to students from various UFSCar courses, LIEC has received young people from other institutions in Brazil and abroad for classes, courses and research at all levels of education.

Partnerships with the industrial sector have marked the history of LIEC in the following years. “The various research themes have been developed, and also changing, from theoretical reflections and from contacts with various companies,” declares Longo. “I emphasize that it was not the production of reflexive knowledge of business needs; on the contrary, such needs have given rise to new interpretive models and dialogues with other theories,” he clarifies.

One of the longest-standing industrial partners is Companhia Siderúrgica Nacional (CSN), with which the laboratory continues to work. Initially, LIEC helped the company eliminate the corrosion that the ceramic burner experienced. “The solution to this problem put the team to research and solve problems related to blast furnace, race channel, torpedo car, converter etc.,” Longo recalled.

Another example cited by Longo is the partnership with 3M of Brazil. LIEC collaborated with the company in the implementation of a varistor plant in Ribeirão Preto, some 100 km from São Carlos. “This collaboration allowed us to open another research sub-area, whereby we produced the first tin oxide varistor,” added the professor emeritus.

Parallel to the projects with companies, LIEC carried out, from the beginning, research in structural ceramics based on zirconia oxide stabilized with rare earths and alkaline earth metals. Thus began the collaboration of the laboratory with the theoretical chemist Juan Andrés, professor of the Universitat Jaume I (Spain) – a cooperation that has lasted for 29 years.

As for the extension activities, LIEC also has successful examples, such as the project through which it brought technical knowledge to artistic ceramics artisans from 9 Brazilian states.

In the 21st century, from multidisciplinary laboratory to materials development center

The year 2000 was a turning point in the scientific trajectory of LIEC. The laboratory was approved in the call for FAPESP CEPID projects, and denominated as Multidisciplinary Center for the Development of Ceramic Materials (CMDMC), and with the guarantee of continuous financing for 11 years. Consequently, the area of diffusion of knowledge was created, international collaborations multiplied (covering more than a dozen countries), and support was given to creating spin-off companies. From this environment came Nanox, specialized in bactericidal nanoparticles, and CosmoScience, dedicated to the characterization of cosmetics.

“This is when LIEC initiated comprehensive modifications in the research of ceramic semiconductors using the Pechini method,” Longo said. “There has been significant expansion in the research on piezoelectric materials, sensors, nanometric particles and thin films for non-volatile memory applications,” affirmed LIEC’s founder.

In 2013, LIEC was again contemplated with the FAPESP CEPID project, now denominated the Center for the Development of Functional Materials (CDMF). In this phase, which continues to this day, the diffusion of knowledge has grown remarkably through the use of social networks and the creation of videos, educational games and radio and television programs. In addition, LIEC researchers have established two spinoffs, NChemi Nanomaterials, of nanomaterials, and Katléia, which specializes in capillary diagnostics. In the scientific research activities, the laboratory has concentrated efforts in obtaining semiconductor nanoparticles with controlled reaction kinetics and morphology.

During the event of the 23rd, Professor Longo thanked everyone who built and still builds the history of LIEC, as well as UFSCar and the funding agencies CAPES, CNPq, FAPESP and FINEP. Finally, Longo addressed a few words to the new generations of researchers who will continue the work. The emeritus professor recommended that they plant new seeds for other crops, and that they create their own models and reinvent themselves.

The emeritus professor’s speech ended with this message: “In these moments of moral and ethical crisis that our country experiences, allied to a silent project of dismantling research and public education at all levels, it is imperative that we gather energies for many present and future confrontations”.

In the first line, from the left, LIEC professors. In the other lines, staff and students of the lab. Photo taken in 2004, at the Chemistry Department of UFSCar.
In the first line, from the left, some LIEC professors. In the other lines, staff and students of the lab. Photo taken in 2004, at the Chemistry Department of UFSCar.

José Arana Varela: Note of Condolences.

It is with deep regret that SBPMat announces the passing of Prof. José Arana Varela of the Chemistry Institute of Unesp, Araraquara, on 05/17/2016. Professor Varela was one of the founders of SBPMat, and its president from 2010 to 2011.

SBPMat sympathizes with the family of Professor Varela, in a sad day when Brazilian science loses one its exponents.

Interview with Professor Jose Arana Varela, honored with the Bridge Building Award from American Ceramic Society.

Professor Arana Varela (to the left) receiving the award. Photo by American Ceramic Society.

On the last January 27th, in Daytona Beach (Florida, United States), during the 38th edition of International Conference and Exposition on Advanced Ceramics and Composites, the Bridge Building Award of the American Ceramic Society was given to a Brazilian for the first time, Professor José AranaVarela, president of our SBPMat from 2010 to 2011. The honor annually distinguishes people from outside the United States who have notably contributed to the field of engineering ceramics.

Graduated in Physics from University of São Paulo in 1968, Arana Varela also has a Master’s Degree in Physics for the Instituto Tecnológico de Aeronáutica (ITA), becoming a Master in 1975. He took his PhD from 1977 to 1981 at University of Washington (United States), conducting research in the field of ceramic materials.

Currently, Arana Varela is Full Professor at Universidade Estadual Paulista Julio de Mesquita Filho (UNESP) and president-director of the executive board of São Paulo Research Foundation (Fapesp), as well as member of the council for competitivity and innovation at São Paulo Federation of Industries (FIESP). Professor Arana Varela is also full member of the Brazilian Academy of Sciences (ABC), among other associations, and member of the editorial body for the journals Ceramics International, Science of Sintering, Cerâmica and Materials Research. Besides, he coordinates the innovation division at the Multidisciplinary Center for Development of Ceramic Materials.

His scientific papers gather over 6,500 citations. In the last 13 years, he has been the author of more than 500 articles, published in international journals. Up to this moment, he has advised and co-advised assignments for over 30 masters and over 40 doctoral theses.

Throughout his career, he has received more than 20 awards from organizations such as American Ceramic Society, Sociedad Española de Cerámica y Vidrio, CNPq, Associação Brasileira de Metalurgia e Materiais and Associação Brasileira de Cerâmica.

A brief interview with the researcher can be seen below:

SBPMat Bulletin: – Tell us a little bit about your story: which were the opportunities and choices that led you to become a researcher in the field of ceramic materials?

José Arana Varela: – Our choice of being a scientist in mateirals started during the Master’s at ITA, in  1972. During this period (in 1975), I met Professor O. J. Whittemore from the University of Washington, Seattle, during his visit to Universidade Federal de São Carlos for a year. As my master’s research was related to a physico-chemical view of thermal decomposition of talcum, which is a ceramic material, Professor Whittemore became interested in it and made some remarks regarding ceramic processing (his specialty). Thence the invitation for a doctorate in Seattle (from 1977 to 1981).

SBPMat Bulletin: – In your own analysis, which were your main contributions to the science and technology of materials? Specifically, can you comment on your main contributions to the field of engineering ceramics, the focus of Bridge Building Award?

José Arana Varela: — As the main theme of our doctoral theses was related to sintering models, we performed a simple study about variable effects, such as water vapor and heating rate in densification and microstructure of magnesium oxide ceramic. We created a model to take into account the structural rearrangement in sintering process.

Considering the evolution on application of ceramic materials in Microelectronics, due to functionality of these materials, we started the Electroceramic line in the 90’s. The functionality initially chosen was resistivity variation with electrical field (ceramic varistors) due to its application, mostly with lightning rods and electric circuits protectors. After understanding and contributing with varistor’s system based on zinc oxide (ZnO), we proposed to change the system considering another semi-conductor (stannous oxide). In this case, we developed throughout the years a stannous oxide varistor with properties that were much superior to traditional ZnO varistors.

Other contributions are related to development of thin ceramic films with Perovskite structure, with the purpose of optimizing their dielectric, piezoelectric and ferroelectric properties by using chemical deposition. We have advanced in the knowledge of chemical deposition, which we call polymeric precursors methods. One of the applications of these films are related to the manufacture of ferroelectric memories. With this, our students have worked in characterizing thin films with ferroelectric properties in some systems such as barium titanate, lead zirconate titanate, as well as strontium niobate and tantalate. A patent in ferroelectric memories, licensed to Panasonic, was proposed by a group led by Professor Carlos Paz de Araujo, at University of Colorado.

The latest contribution is related to sensors with nanometric structure, in collaboration with a group led by Professor Harry Tuller at MIT. Recent results were very promising and they showed great sensitivity in nanosensors based on stannous monoxide. It is important to point out that we have recently applied for patent regarding this study.

SBPMat Bulletin: – “Bridge building”, building bridges. Can you share with us a retrospective on the main bridges built throughout your career and the ones you would like to build?

José Arana Varela: — Our bridges have been built from the moment we finished our PhD at University of Washington. I continued to collaborate with Professor Whittemore for decade and I started other partnerships with Professor Gary Messing at Penn State University e then Professor Richard Bradt at University of Alabama.

Concurrently, we had joint projects in Europe with Professor João Baptista at Universidade de Aveiro, Portugal and with Doctor José Fernandez from Institute of Ceramics and Glass in Madrid, related to the subject of Electroceramics. We began to collaborate with groups in Bordeaux, France (Professor Marc Onillon), as well as André Perrin at University of Rennes. The collaborations proceeded with groups led by Professor Paolo Nanni at University of Genoa, concurrently with group led by Professor Danilo Suvorov at Josef Stephan Institute, in Slovenia and Professor Harry Tuller at MIT, in Boston.

SBPMat Bulletin: — Would you like to leave a message for our readers who are developing their academic or industry career as materials researchers?

José Arana Varela: — Science of Materials is fundamental to developing new useful technologies that will resolve society’s greatest problems. Great advancement in knowledge of ceramic materials, mostly their application in production of energy, communication, environmental control, etc., has been increasing in the past 20 years, mainly because of increased collaboration among researchers in different parts of the world. Science of Materials stopped being polarized between the United States and Europe (Germany, England and France) and it relies on contributions from other players in Asia and certainly Brazil. Fundamental knowledge of mass and charge transportation mechanisms, as well as structure of materials in nanometric scale, is essential to new developments and advances in technology.