Architecting a 1T-phase material with metal NPs enriching HER kinetics in alkaline and seawater electrolytes

Creating sophisticated and captivating electrocatalysts to produce hydrogen is extremely attractive but highly challenging with noble metal (NM)-free catalysts. The production of hydrogen fuel through seawater electrolysis is an advancing sustainable alternative for mass utilization. In this work, we constructed CuS nanoparticles (NPs) on a thin 1T phase of WS₂/WO₃ heterointerface, stabilized by ammonium ion (NH₄⁺) intercalation (Cu@1T-N-W NSs). The developed NPs on a thin metallic sheets achieves high electrical conductivity and enhanced intrinsic activity in all of the edges and both basal planes. The Cu@1T-N-W NS required only 121.8 mV and 158.2 mV to achieve 10 mA cm⁻² in 1 M KOH and natural seawater + 1 M KOH electrolytes, respectively. An operando EIS study reveals the complete electron-ion transportation and faster kinetics with various potentials. This work provides a unique path to design an NM-free catalyst with a stable metallic 1T phase for efficient hydrogen generation in alkaline and seawater electrolysis.