Potassium electrochemical optimization of MoS2 catalytic hydrogen evolution reaction performance

Abstract

Transition metal dichalcogenides, particularly molybdenum disulfide (MoS2), are gaining attention for their abundant resources, low cost, and high catalytic activity. However, challenges such as agglomeration, poor electrical conductivity, and low active site density limit their use in hydrogen evolution reactions (HER). This study presents a flexible self-supporting catalytic electrode, C@MoSx@pCNF, developed through potassium electrochemical intercalation. This method fragments the MoS2 nanosheets encapsulated in conductive carbon into smaller lamellas, transforming them into an amorphous structure. Compared to crystalline MoS2, the amorphous MoSx exhibits increased active sites and enhanced superhydrophilic and superhydrophobic properties. Under acidic conditions, the C@MoSx@pCNF electrode shows a low overpotential of 51 mV at a current density of 10 mA cm-2 with a Tafel slope of 77 mV dec-1, highlighting its exceptional HER performance and providing a new approach to enhance the catalytic efficiency of MoS2.