In Memoriam - Luis A. Avaca (1940–2021)
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2021-07-01 |
| Journal | Electroanalysis |
| Authors | Romeu C. Rocha‐Filho, Greg M. Swain |
| Institutions | Michigan State University, Universidade Federal de São Carlos |
Abstract
Section titled “Abstract”Luis was born in Buenos Aires, Argentina, on the 27th of March of 1940. He obtained a degree in Chemical Sciences from the Universidad de Buenos Aires in 1963. He continued working there as a teaching assistant until 1966. After spending one year as a visiting teacher at the Universidad de los Andes, in Venezuela, he moved to England and in September of 1971 obtained a Ph.D. in electrochemistry from the University of Southampton, under the supervision of Alan Bewick. Immediately after, he became a postdoctoral research assistant at the Queen Mary College of the University of London, doing research related to organic electrochemistry under the supervision of James H. P. Utley until October of 1973. In the next month he moved to Brazil, to work as a faculty member of the Institute of Physics and Chemistry of São Carlos of the University of São Paulo (IFQSC-USP), where the offering of graduate (1971) and undergraduate (1973) courses in chemistry had been recently started. In 1994, the IFQSC was split into the Institute of Physics of São Carlos and the Institute of Chemistry of São Carlos. Luis would retire from the latter as a full professor in March of 2010. During his 36 years in the University of São Paulo, Luis supervised 21 MSc and 20 PhD students as well as several postdoctoral fellows; a great number of whom are now professors of chemistry at different Brazilian universities. Among his students, he was known to be rigorous, meticulous and methodic, besides being focused on conceptual explanations. “There was no point in arguing with him without knowing how to explain what had been observed and obtained in a particular experiment. The cycle was: you do not know how to explain, you have to go back and further study until you can explain the physical phenomenon in detail. With that, whoever underwent his supervision was polished and really prepared for the scientific world outside and inside the academic walls” (Boletim Eletrônico da SBQ 2021, 1449. http://boletim.sbq.org.br/noticias/2021/n3570.php). Luis published over 150 peer-reviewed manuscripts during his academic career. He was a leader in promoting conducting diamond electrodes and research with them in electrochemistry. His work impacted two areas applying diamond electrodes: (i) electroanalysis and (ii) electrochemical-assisted chemical waste remediation. Luis and his group published on several topics over the years, but we highlight a couple of these here. First, regarding the structure-property relationships of boron-doped diamond electrodes, Luis’ team reported on the cathodic pretreatment of diamond electrodes to change surface chemistry and activate them for electron transfer. At the time the work was published in multiple papers, researchers knew that the hydrogen-terminated diamond electrode exhibited the most rapid electron-transfer kinetics for soluble aqueous redox systems. It was also recognized at the time that increasing the coverage of surface oxygen functional groups tended to make electron transfer more sluggish. One solution to this problem is hydrogen plasma treatment. However, most laboratories do not have access to a microwave plasma system for such surface pretreatment. Luis’s team learned that diamond surfaces could be rehydrogenated during cathodic polarization (e. g., Electrochim. Acta 2004, 49, 4021-4026). The pretreated conditions were optimized and generally involve potentiostatic polarization at negative potentials (e. g. −3 V vs. Ag/AgCl) in acidic electrolyte solution. This work was quite an important finding as it demonstrated an easy way to pretreat and reactivate diamond electrodes. The second area is electroanalysis. Luis’ group reported a number of elegant examples of using boron-doped diamond electrodes for the sensitive, reproducible, and stable detection of analytes like nicotine (Anal. Lett. 2005, 38, 1587-1599), pharmaceuticals like lidocaine (Electroanal. 2007, 19, 1189-1194) and pesticides such as carbaryl (Electroanal. 2006, 18, 253-258). Consistent with his philosophy of training graduate students and postdoctoral researchers, his papers were well written and organized, presented important new science, and consisted of thorough explanations of the results. Luis was an interdisciplinary scientist and conducted research studying hydrogen and oxygen evolution and water electrolysis on several electrocatalytic metals and alloys. He also worked in the area of corrosion science studying passivating coatings, such as sol gels, for stainless steel and other metals. Avaca got involved with diamond electrodes through his friendship with Christos Comninellis, who he met at ISE. [Pictured are Luis Avaca (left) and Christos Comninellis]. In fact, his first diamond electrodes were provided by the group at the Center Suisse de Electronique et de Microtechnique SA (CSEM) through Comninellis, and in 2004 he participated in the 7th Workshop Diamond Electrodes, in Interlaken, Switzerland. Luis was a warm-hearted and supportive individual, friend, and colleague. He cared deeply about his family and students. He will be missed. May his memory be a blessing to his family and friends!