Strengthening heterogeneous strain in FeCoNiMo-based high-entropy alloys for advanced energy conversion

Inducing lattice distortion and applying strain between atoms to regulate the electronic structure is an effective strategy for optimizing catalytic activity; however, several challenges still remain. Herein, heterogeneous strain triggered by large-radius atoms is proposed to effectively optimize the electronic structure and energy level of FeCoNiMo-based High-entropy alloys, thereby significantly enhancing alkaline hydrogen evolution and triiodide reduction reaction performance. Following the introduction of large-radius atoms such as Nb, W or Ta into FeCoNiMo-based HEA catalysts, the overpotential at eta 10 was reduced by more than half (from 172 to 84 mV). Using FeCoNiMoNb/C as the counter electrode in photovoltaic devices, a PCE of 8.50 % was achieved, which is higher than that of FeCoNiMo- and Pt-based photovoltaic devices. This study leverages large-radius atoms to trigger strengthened heterogeneous strain within HEA catalysts, providing an innovative approach to effectively regulate their electronic structures and develop high-performance, low-cost bifunctional HEA catalysts.