Hierarchical Cobalt–Nickel Phosphide/Molybdenum Disulfide Hybrid Electrocatalyst Triggering Efficient Hydrogen Generation in a Wider pH Range
Xiaoxiao Cheng, Yun Tong
Abstract
Structural engineering of the molybdenum disulfide (MoS 2 ) retains its importance for the application of the hydrogen evolution reaction (HER) in a full pH range. However, the catalytic performance of reported MoS 2 -based materials, especially in neutral conditions, is unsatisfactory. Herein, an effective synergy between CoP, Ni 2 P, and MoS 2 nanosheets is established via a simple strategy, which constructs a self-supporting (CoP/Ni 2 P/MoS 2 –CC) electrode endowed with abundant catalytic active sites, optimal electronic structure, and improved charge transfer capability. The optimized CoP/Ni 2 P/MoS 2 –CC sample shows low overpotentials of 335, 119, and 211 mV at 100 mA cm –2 in neutral, alkaline, and acidic electrolytes with small Tafel slopes of 63, 62, and 82 mV dec –1, respectively. Remarkably, the catalytic performance in neutral medium is superior to that of most of the reported MoS 2 -based hybrid electrocatalysts. Our work proves a facile and feasible strategy to promote the pH-universal catalytic activities of MoS 2 -based heterogeneous structures for hydrogen production.