Electrochemical Reduction of Nitrate to Ammonia Catalysed by Single Atoms and Metallic Oxides

• Grant number: 24/03807-7
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2025
• End date: January 31, 2028
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Raphael Nagao de Sousa
• Grantee: Raphael Nagao de Sousa
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated scholarship(s): 25/03895-6 - ELECTROREDUCTION OF NITRATE TO AMMONIA ON Co3O4/Ag2O TANDEM ELECTRODES, BP.PD

Abstract

Nitrogen gas, as the main component of air, has been used for mass ammonia production for over a century, providing enough nutrition for agriculture and the world population growth. In recent years, significant effort has been made to develop sustainable production processes of ammonia under mild conditions, with the aim of addressing the intensive energy consumption and high carbon emissions associated with the traditional Haber-Bosch process. Among various approaches, the electrochemical nitrate reduction reaction (NO3RR) stands out, which allows the simultaneous removal of nitrate from contaminated streams and the generation of ammonia using renewable electricity as an energy source. In this project, we propose the use of two classes of electrocatalysts to improve the performance of this reaction, namely: single atoms (Co, Cu, Ni and Fe) supported on bidimensional matrixes (PHI and NC) and nanostructured (plates and wires) metal oxides (Co3O4, Cu2O and Ag2O) based on transition metals. Both alternatives have physicochemical properties required to reduce the high overpotential to trigger the reaction and to increase Faradaic efficiency followed by high yield rates of ammonia production. The focus of this project is not only to evaluate the electrochemical performance of the material, but to identify the electrocatalyst's active sites and the adjustment of its activity with the aid of in situ monitoring of the reaction intermediates along with the electronic and structural material properties using operando X-rays absorption spectroscopic advanced techniques. (AU)