Multi‐Elemental Electronic Coupling for Enhanced Hydrogen Generation

A robust polyaniline‐assisted strategy is developed to construct a self‐supported electrode constituting a nitrogen, phosphorus, sulfur tri‐doped thin graphitic carbon layer encapsulated sulfur‐doped molybdenum phosphide nanosheet array (NPSCL@S‐MoP NSs/CC) with accessible nanopores, desirable chemical compositions, and stable composite structure for efficient hydrogen evolution reaction (HER). The multiple electronic coupling effects of S‐MoP with N, P, S tri‐dopants afford effective regulation on their electrocatalytic performance by endowing abundant accessible active sites, outstanding charge‐transfer property, and d‐band center downshift with a thermodynamically favorable hydrogen adsorption free energy ( Δ G H* ) for efficient hydrogen evolution catalysis. As a result, the NPSCL@S‐MoP NSs/CC electrode exhibits overpotentials as low as 65, 114, and 49 mV at a geometric current density of 10 mA cm −2 and small Tafel slopes of 49.5, 69.3, and 53.8 mV dec −1 in 0.5  m H 2 SO 4 , 1.0  m PBS, and 1.0  m KOH, respectively, which could maintain 50 h of stable performance, almost outperforming all MoP‐based catalysts reported so far. This study provides a valuable methodology to produce interacted multi‐heteroatomic doped graphitic carbon‐transition metal phosphide electrocatalysts with superior HER performance in a wide pH range.