Facile Synthesis of Heterogeneous Indium Nanoparticles for Formate Production via CO2 Electroreduction

Ana Cristina Pérez-Sequera; Manuel Antonio Diaz-Perez; Mayra Anabel Lara Angulo; Juan P Holgado; Juan Carlos Serrano-Ruiz

doi:10.3390/nano13081304

Facile Synthesis of Heterogeneous Indium Nanoparticles for Formate Production via CO₂ Electroreduction

Nanomaterials (Basel). 2023 Apr 7;13(8):1304. doi: 10.3390/nano13081304.

Authors

Ana Cristina Pérez-Sequera¹, Manuel Antonio Diaz-Perez¹, Mayra Anabel Lara Angulo¹, Juan P Holgado², Juan Carlos Serrano-Ruiz¹

Affiliations

¹ Materials and Sustainability Group, Department of Engineering, Universidad Loyola Andalucía, Avda. de las Universidades s/n, 41704 Dos Hermanas, Spain.
² Instituto de Ciencia de Materiales de Sevilla and Departamento de Química Inorgánica, CSIC-Univ de Sevilla, Av. Américo Vespucio, 49, 41092 Seville, Spain.

Abstract

In this study, a simple and scalable method to obtain heterogeneous indium nanoparticles and carbon-supported indium nanoparticles under mild conditions is described. Physicochemical characterization by X-ray diffraction (XRD), X-ray photoelectron microscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed heterogeneous morphologies for the In nanoparticles in all cases. Apart from In⁰, XPS revealed the presence of oxidized In species on the carbon-supported samples, whereas these species were not observed for the unsupported samples. The best-in-class catalyst (In₅₀/C₅₀) exhibited a high formate Faradaic efficiency (FE) near the unit (above 97%) at -1.6 V vs. Ag/AgCl, achieving a stable current density around -10 mA·cm_geo^-2, in a common H-cell. While In⁰ sites are the main active sites for the reaction, the presence of oxidized In species could play a role in the improved performance of the supported samples.

Keywords: CO2 conversion; CO2 electroreduction; carbon-supported materials; formate production; heterogeneous catalysts; indium catalysts.

Grants and funding

J.C.S.R. would like to thank the Spanish Ministry of Science and Innovation for financial support through the Ramón y Cajal Program, Grant: RYC-2015-19230 and the Research, Development and Innovation projects program, Project number: PID2019-108453GB-C22.