Evaluation of vacancies in Ni/CeO2 catalysts in CO2 reduction: an operando study

Abstract

Developing materials for appropriate CO2 reduction is a global issue and is mandatory nowadays. The chemical properties of Ni/CeO2 are particularly favorable for reducing CO2 to methane. The methodologies to achieve this objective involve structuring these materials through crystals of different morphologies, sizes, and textures. Vacancies positively affect the catalyst's activity, these can be understood using the operando methodology. The challenge of heterogeneous catalysis for this reaction is the development of catalysts resistant to coke formation and sintering so that they remain active throughout the reaction, providing higher conversions and selectivity. Using time-resolved operando Raman spectroscopy will enable elucidating of the behavior of catalysts during activation and catalytic reaction. They are very suitable for assessing catalyst structure and performance during reaction simultaneously. Specifically, bands associated with oxygen vacancies are detectable in Ni/CeO2 catalysts, but there is still little understanding in the literature of how vacancies behave during the CO2 methanation reaction. This project is associated with Marcela de Andrade Lucas, Research Internship Abroad (BEPE-FAPESP), from Universidade Estadual Paulista (Brazil) to the Institute of Catalysis and Petroleum Chemistry (ICP, CSIC, Spain), starting in September (forecast) and by three months scholarship.