Synergistic integration of self-supported 1T/2H-WS₂ and nitrogen-doped rGO on carbon cloth for pH-universal electrocatalytic hydrogen evolution

Hydrogen economy based on electrochemical water splitting exemplified one of the most promising means for overcoming the rapid consumption of fossil fuels and the serious deterioration of global climate. The development of earth-abundant, efficient, and durable electrocatalysts for hydrogen evolution reaction (HER) plays a vital role in the commercialization of water electrolysis. Regard, the self-supported electrode with unique nitrogen-doped reduced graphene oxide (N-rGO) nanoflakes and WS₂ hierarchical nanoflower that were grown directly on carbon cloth (CC) substrate (WS₂/N-rGO/CC) was successfully synthesized using a facile dual-step hydrothermal approach. The as-synthesized 50% 1T/2H-WS₂/N-rGO/CC (WGC), which possessed high metallic 1T phase of 57% not only efficiently exposed more active sites and accelerated mass/charge diffusion, but also endowed excellent structural lustiness, robust stability, and durability at a high current density. As a result, the 50% WGC exhibited lower overpotentials and Tafel slopes of 21.13 mV (29.55 mV∙dec⁻¹) and 80.35 mV (137.02 mV∙dec⁻¹) as compared to 20% Pt-C/CC, respectively for catalyzing acidic and alkaline hydrogen evolution reactions. Pivotally, the as-synthesized 50% WGC also depicted long-term stability for more than 8 h in the high-current-density regions (100 and 220 mA∙cm⁻²). In brief, this work reveals a self-supported electrode as an extraordinary alternative to Pt-based catalysts for HER in a wide pH range, while paving a facile strategy to develop advanced electrocatalysts with abundant heterointerfaces for practical applications in energy-saving hydrogen production.