High‐Entropy Nitrides as Superior Electrocatalysts: Unveiling the Role of Entropy in Enhanced Performance
Jinpei Hei, Nannan Wang, Rui Jing, Xiaodong Chen, Xiaojie Yin, Jing Li, Peng Zuo, Yanjun Yin, Lifeng Cui
Abstract
High-entropy nitrides (HENs) are emerging as promising electrocatalysts due to their diverse elemental composition, tunable electrochemical properties, and a wide range of active sites that enhance adsorption and oxidation reactions. However, the unclear role of entropy has limited their full potential in electrocatalysis. In this study, we introduce a novel and straightforward method for synthesizing (CoNiCuVW)N with variable entropy levels using halite as a molten salt. By exploiting the synergistic effects of multiple metal components, we achieve robust bonding between the N-doped carbon substrate and HEN nanoparticles, resulting in a homogeneous element distribution. This uniformity leads to exceptional catalytic performance for the oxygen reduction reaction (ORR) in alkaline electrolytes, with an onset potential of 0.96 V and a half-wave potential of 0.91 V. Additionally, HEN-based zinc-air batteries exhibit impressive performance, achieving 1.55 V and maintaining 60% roundtrip efficiency over approximately 400 cycles. Density functional theory (DFT) calculations suggest that the high-entropy, homogeneous distribution of elements enhances active site availability, modulates electronic structure, and optimizes kinetics, thereby lowering reaction barriers during the ORR. This work not only facilitates the development of structurally ordered HEN nanoparticles but also lays the foundation for further exploration in electrochemical applications.