Journal of Fundamentals of Renewable Energy and Applications
Open Access
ISSN: 2090-4541
+44 1300 500008
ISSN: 2090-4541
+44 1300 500008
Ioan Cezar Marcu
University of Bucharest, Romania
Keynote: J Fundam Renewable Energy Appl
The electronic and redox properties of oxide-based catalysts strongly influence their catalytic performance in oxidation reactions. A useful and highly sensitive technique to characterize them is the in situ electrical conductivity measurement. This allows to gain insight into the key features of the redox catalysts that determine their catalytic performance in order to better understand the origin of the catalytic effect and the reaction mechanism involved and, consequently, to improve the catalysts on a scientific basis or to rationally design efficient new ones. The oxidation catalysts are semiconducting metal oxides and function during catalysis via a heterogeneous redox mechanism involving the reduction and re-oxidation of the solid in the catalytic cycle. This behavior can be studied by following the evolution of the electrical conductivity of the oxide as a function of the nature of the gas phase in contact with this. For example, in the presence of oxygen the electrical conductivity of an n-type oxide decreases, while in the presence of reducing molecules, such as hydrocarbons, H2, CO, which consume lattice oxygen species, it increases. In this work, electrical conductivity studies of several oxide-based catalysts have been performed as a function of temperature and oxygen partial pressure. Also, temporal responses during sequential exposures to different gaseous atmospheres, including the reaction mixture, in conditions similar to those of catalysis were analyzed. Correlations between their redox properties and their catalytic performance in different oxidation reactions have been established and the origin of their catalytic behavior has been elucidated.
Ioan Cezar Marcu completed his PhD in Catalysis in 2002 at the Institute of Catalysis – University Lyon 1, France, and Postdoctoral studies in 2007 at the Institute Charles Gerhardt Montpellier, France. He received his Habilitation in Catalysis in 2013 and is now Associate Professor of Chemical Technology and Catalysis at UB and Senior Researcher at the Research Center for Catalysts and Catalytic Processes of UB. His research interests cover the field of catalysis by metal oxides. He published more than 70 papers including a book chapter and has been serving as an Editorial Board Member of two international journals.