High-power hybrid alkali-acid fuel cell for synchronous glycerol valorization implemented by high-entropy sulfide electrocatalyst

Abstract

Developing highly efficient electrocatalysts for selective glycerol oxidation reaction (GOR) is crucial to implement biomass valorization and to advance the energy conversion efficiency of glycerol fuel cells. Herein, a hybrid alkali-acid direct glycerol fuel cell (DGFC) that can not only deliver a high power density but also enable glycerol valorization conversion is demonstrated. Such double-benefits electrochemical device is implemented by in situ growth of FeCoNiCrMnS2 nanoparticles on carbon cloth (FeCoNiCrMnS2/CC) as anode, which exhibits high activity and selectivity for GOR with low overpotential and high Faradaic efficiency toward the formate product. Based on the results of finite element method simulations of element distribution on FeCoNiCrMnS2, the electrocatalytic sites was investigate by density functional theory in conjunction with Monte Carlo and machine learning simulations and confirmed that the desired catalytic properties primarily originate from the Ni and Co sites, while Cr and Mn optimized the electronic structure of these sites. The as-developed DGFC can release a maximum peak power density of 50.1 mW cm−2 and stably generate formate with high selectivity. The present work may inspire to contrive the newly advanced energy device and provide fresh impetus for the development of newly high-entropy materials for a variety of application.