Featured scientist: interview with Carlos Graeff.

Prof. Carlos Graeff
Prof. Carlos Graeff

Fascinated by science since he was a child, with a representative at his home (his father, a renowned neuroscientist), Carlos Frederico Oliveira Graeff, born at Ribeirao Preto (state of São Paulo), chose the area of Physics as his university studies. He obtained his bachelor’s (1989), master (1991) and doctor (1994) degrees in Physics from the University of Campinas (Unicamp). During his master’s and doctorate program, supervised by professor Ivan Chambouleyron, he took his first steps as a researcher in the Materials area with studies on materials based on germanium and silicon. During his doctorate he participated in a research internship at the Max Plank Institut für Festkörperforschung in Germany.

He returned to Germany in 1994 until 1996 for a postdoctoral period to work on electronic magnetic resonance, semiconductors and electronic devices at the Walter Schottky Institute of the Technische Universität München (TUM), with a grant from the German foundation Alexander Von Humboldt.

Upon returning to Brazil, he became a professor at the Department of Physics and Mathematics of the University of São Paulo (USP), where he remained for 10 years. In 2006, he joined the Faculty of Sciences of Bauru at the State University of São Paulo (UNESP) as a full professor, where he is still teaching and researching. Throughout his academic career, Graeff has been visiting professor or researcher at several institutions in France, China and Switzerland.

From 2007 to 2009, Graeff was coordinator of the Post-Graduate Program in Materials Science and Technology (POSMAT) at UNESP – Bauru campus. Between 2009 and 2014, he was the coordinator of the newly created Materials Area of CAPES, responsible for the evaluation of Brazilian post-graduate programs in Materials, among other functions. From 2011 to 2013, Graeff was president of the Humboldt Club of Brazil and in 2012 and 2013 he was scientific director of B-MRS. The scientist also fulfilled or performs management or advisory functions at Brazilian agencies FAPESP and CAPES, and at IUPAC (International Union of Pure and Applied Chemistry).

In 2017, after having participated in the editorial board of several international journals, he was appointed associate editor in the photovoltaic area of the journal Solar Energy (impact factor 4,018), of Elsevier publishing house. Also in 2017, he became Dean of Research at UNESP, a post he holds until now.

With an h index of 28, Graeff is the author of about 200 indexed papers that have more than 2,500 citations, according to Google Scholar. In three decades of scientific work, together with his team at the Laboratory of New Materials and Devices at UNESP and his numerous national and international collaborators, Graeff has contributed to the field of materials research with multiple subjects. Among his most cited articles there are studies on synthetic diamond, silicon and germanium heterostructures, conjugated polymers, latex and melanin (biological material with semiconductor properties that are promising for the development of bioelectronic devices).

The researcher has also worked in the area of photovoltaic energy (direct conversion of solar radiation into electricity), with numerous contributions to the development of solar cells based on different materials (dyes, perovskites and organic semiconductors). On this subject of photovoltaic energy, Carlos Graeff will offer a plenary lecture at the XVII B-MRS Meeting, to be held in Natal (RN) from September 16 to 20.

The following is an interview with this outstanding researcher of our community.

B-MRS Newsletter: How or why did you become a scientist? Did you always want to be a scientist? Also, briefly tell us what led you to work in the field of materials.

Carlos Graeff: My father, Frederico Graeff, is a well-known researcher and perhaps one of the most important influences in my decision. My aunts were also teachers and researchers, so from an early age I had access to the world of science from my home, which has always fascinated me. The decision to study physics was largely due to the various books I read and from the television Cosmos series presented by Carl Sagan. The decision to work in the Materials area came later on during my baccalaureate in physics after the first courses in condensed matter physics and semiconductors. From the beginning of the graduate studies I worked in materials, and soon I was attracted by the interfaces of physics with chemistry and biology in very different subjects of materials science and engineering.

B-MRS Newsletter: What do you believe are your main contributions to the Materials area? Please consider all aspects of scientific activity.

Carlos Graeff: It is always difficult to choose key contributions. In my case in particular it is easy to see, reading my CV, a very eclectic trajectory in terms of studied materials and applications. Using originality as a preference, I will dwell on three themes; the first is the production of CoS (cobalt sulfide) the basis of ecological paints for the production of electrodes for solar cells. We have achieved a simple, industrial and ecological method to replace platinum in dye-based solar cells. In the second theme, we have proposed several alternative methods for the synthesis of melanin, the material involved in tanning, and with this we have been able to produce biocompatible materials with very special characteristics with regard to, for example, solubility. We are identifying a very important defect for this material using, as a main tool, computational simulations combined with spectroscopic techniques. We are sure this material will be important in the emerging area of bioelectronics. In the third theme, we describe in detail the whole degradation process of organic semiconductors, identifying routes for the production of high sensitivity dosimeters for applications in hospitals and clinics that use, for example, gamma rays for cancer treatments and diagnosis. We also have had very unique contributions in the physics of electrically detected magnetic resonance, increasing the sensitivity and the general understanding of the physical phenomena involved. In addition to these fundamental contributions, I was responsible, proudly and with satisfaction, for the implementation of the materials area at CAPES. Another source of satisfaction regards the good students I was fortunate enough to mentor, many of them brilliant scientists. I helped and coordinated the assemblage of several laboratories both here in Brazil and abroad, most recently I helped set up a magnetic resonance laboratory in China.

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

Carlos Graeff: I started my master’s degree in 1989, a time that was perhaps as troubled as the current one, do not get discouraged! With focus and a bit of luck it is always possible to create new ideas, build a solid career and contribute to our beautiful country. We are going through a great revolution, with the emergence of new technologies that will profoundly transform society. Intelligence will increasingly play a decisive role in the direction of our society, be prepared to work in this new world of great opportunities. Always seek out dialogue with specialists from the most different areas of knowledge and from various countries. Quite possibly, in the coming years we will unravel the mysteries of how the brain works, we will master limitless forms of energy and ecological production, generate artificial intelligence. Open up to what is new, be bold, Brazil needs your citizen and entrepreneurial spirit.

B-MRS Newsletter:  You will deliver a plenary lecture at the XVII B-MRS Meeting. Leave an invitation to our community.

Carlos Graeff: Photovoltaic energy is reaching its commercial maturity, we are living an unprecedented energy revolution. In the lecture I will show some updated data on the perspectives of using photovoltaic cells in Brazil and in the world; its principles of operation; the challenges for scientists and material engineers in this relentless race for increasingly efficient, durable and environmentally friendly materials, processes and devices. I will present our group’s latest results on this topic.