Synthesis and characterization of high-entropy oxides (HEO) and their medium- (MEO) and low-entropy (LEO) analogues derived from metal glycerolates for green hydrogen production from water electrolysis

• Grant number: 25/15836-4
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2025
• End date: September 30, 2027
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Josué Martins Gonçalves
• Grantee: João Lucas Gonçalves de Sousa Borges
• Host Institution: Instituto Mackenzie de Pesquisas em Grafeno e Nanotecnologias (Mackgraphe). Universidade Presbiteriana Mackenzie (UPM). São Paulo , SP, Brazil
• Associated research grant: 23/17560-0 - Designing new high-entropy coordination compounds via spray-drying and their derivatives for energy conversion and storage, AP.JP

Abstract

This project proposes the synthesis and characterization of high-entropy oxides (HEOs), as well as their medium-entropy (MEOs) and low-entropy (LEOs) analogs, derived from metal glycerolate (M-Gly) precursors obtained via spray drying. These materials will be applied as electrocatalysts for green hydrogen production through water electrolysis, a strategic technology in the global energy transition toward decarbonization. The proposal includes the development of two distinct material series: one focused on the hydrogen evolution reaction (HER), based on Ni, Co, Cu, Mn, and Mo; and another for the oxygen evolution reaction (OER), using Ni, Fe, V, Mn, and Mo. These metals were selected for their relative abundance, reported catalytic performance, and their synergistic behavior when combined in high-entropy systems. The material synthesis will involve calcination steps at different temperatures (400, 600, and 800¿°C) in an oxidizing atmosphere, aiming to obtain hollow and porous spheres with a spinel-type structure (AB¿O¿), optimized for electrocatalytic applications. The physicochemical characterization will include techniques such as X-ray diffraction (XRD), Raman and FTIR spectroscopy, thermal analyses (TGA/DSC), scanning and transmission electron microscopy (SEM and TEM), and EDS mapping. These analyses will be supported by state-of-the-art infrastructure available at national laboratories, where in-situ experiments will be conducted to monitor the formation of electrochemically active crystalline phases. The resulting materials will be incorporated into catalytic inks and applied onto glassy carbon electrodes, to be tested in three- and two-electrode electrochemical cell configurations for performance evaluation in HER and OER. The project aims to identify multimetallic compositions that outperform conventional noble-metal-based catalysts, contributing to more sustainable and economically viable solutions in the context of the green hydrogen economy. The proposal presents an innovative approach by employing metal glycerolate-based precursors and leveraging the concept of configurational entropy as a design tool for novel catalytic materials. The project is expected to generate frontier knowledge and unprecedented results with potential for intellectual property protection and publication in high-impact journals in the field of energy materials.