Mulberry‐Inspired Nickel‐Niobium Phosphide on Plasma‐Defect‐Engineered Carbon Support for High‐Performance Hydrogen Evolution

Bimetallic phosphate electrocatalysts on carbon‐cloth support are among the most promising industry‐relevant solutions for electrocatalytic hydrogen production. To address the persistent issue of hetero‐phase interfacing on carbon support while ensuring high activity and stability, a low‐cost, high‐performance hydrogen evolution reaction (HER) electrocatalyst is developed. Bi‐phase Ni12P5‐Ni4Nb5P4 nanocrystals with rich heterointerfaces and phase edges are successfully fabricated on carbon cloth (CC), which is enabled by intentional defect creation by atmospheric pressure dielectric barrier discharge (DBD) plasma (PCC). The obtained Ni12P5‐Ni4Nb5P4/PCC electrocatalyst exhibits excellent HER performance, heralded by the low overpotentials of 81 and 287 mV for delivering current densities of 10 (j10) and 500 (j500) mA cm−2, respectively. Meanwhile, the Ni12P5‐Ni4Nb5P4/PCC maintains spectacular catalytic activity at high current density region (>j615), which outperformed the industry‐relevant benchmark Pt/C/PCC catalyst. The catalyst grown on the plasma‐treated support shows remarkably longer operation and ultra‐stable electrocatalytic characteristics over 100 h continuous operation. Ab initio numerical simulations reveal that Ni atoms exposed in the heterointerfaces act as the main catalytically active centers for HER. Ni–Nb phosphides resembling mulberry structures are successfully prepared on the surface of plasma‐treated carbon cloth. Owing to the intentional defect creation by the plasma, the electrocatalytic activity and stability of the Ni12P5‐Ni4Nb5P4/PCC catalyst are improved. The overpotential at a current density of 10 and 500 mA cm−2 is only 81 and 287 mV in an alkaline electrolyte, respectively.