Historical experimental data and theoretical volcano map-accelerated cross-scale design of a highly active and durable ternary alloy electrocatalyst for formic acid oxidation

Abstract

Traditional studies in comprehensive multicomponent spaces driven by redundant chemical experiments may overlook important features. Herein, we introduce historical experimental data and a theoretical volcano map, coupled with thermodynamic stability, to provide insights by feature ranking based on a robust formic acid oxidation reaction (FOR) database. Results indicate that the PdCuNi alloy catalyst screened by density functional theory (DFT) calculations and machine learning (ML) is a promising candidate for FOR. Electron-deficient surface Ni atoms promote the reduction of the thermodynamic energy barrier of FOR. A PdCuNi medium entropy alloy aerogel (PdCuNi AA) was successfully synthesized through a simple one-pot NaBH₄-reduction synthesis strategy. The obtained catalyst exhibits a mass activity of 2.7 A mg⁻¹, surpassing those of PdCu, PdNi and commercial Pd/C by approximately 2.1-, 2.7- and 6.9-fold, respectively. Moreover, PdCuNi AA achieves an impressive power density of around 153 mW cm⁻² with 0.5 mg cm⁻² loading in the anode of direct formic acid fuel cells. Combining cutting-edge methods to drive innovative catalyst design will play a key role in advancing the development of fuel cells.