In situ investigation of the catalytic activity of cerium (IV) oxide nanoparticles over alpha,beta-unsaturated compounds using Raman spectroscopy

• Grant number: 22/12491-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2022
• End date: February 29, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Italo Odone Mazali
• Grantee: Gustavo Damasceno Lima de Andrade
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 14/50906-9 - INCT 2014: in Functional Complex Materials, AP.TEM
• Associated scholarship(s): 23/07570-9 - Study of catalytic activity of ceria nanorods using batch reactor and advanced surface characterization of the catalyst, BE.EP.IC

Abstract

Heterogenous catalysis is an interesting alternative for the selective reduction of ±,²-unsaturated carbonyl compounds. Recent study shows the eficiency and selectivity of the reduction of crotonaldehyde to crotyl alcohol when using CeO2 nanorods, and the adsoption of different ±,²-unsaturated compounds on CeO2 has already been reported in literature. Thus, nanorods of this non-stoichiometric oxide is an option for the application in crotonaldehyde catalysis. Specifically, the oxygen vacancies that are present in the CeO2 nanorods have a prominent role in guaranteeing the selectivity and efficiency of the reation. The study of the oxygen vacancies concentration in CeO2 was shown possible using the in situ Raman spectroscopy technique. Therefore, this project proposes the study of the formation and consumption of oxygen vacancies on the surface of CeO2 nanorods using in situ Raman spectroscopy, while the nanoparticles act as catalysts of the reduction of diferent ±,²-unsaturated carbonyl compounds. Such accompaniment will allow a better comprehention of the role of non- stoichiometric deffects in the reations that are catalyzed by this material. Furthermore, the nanorods will be treated through different processes, those being cominution and leaching, and the impacts of such treatments over the reversibility of oxygen vacancies during the catalysis will be observed. The selective reduction of ±,²-unsaturated carbonyl compounds to unsaturated alcohols using CeO2 nanoparticles would represent a valuable advance in different industries, given the great importance of these alcohols as intermediates in production chains of drugs, flavourings and fragancies. The ±,²-unsaturated carbonyl compounds that will be studied are crotonaldehyde, 2-methylcrotonaldehyde, mesityl oxide and cinnamaldehyde.