Ionic Surfactant-Modified Few-Layer MoS₂ for High-Efficiency Solar-Driven Electrocatalytic Water Splitting

The quest to eliminate environmentally harmful fuels is underway, with green hydrogen emerging as a promising solution. In this study, we developed a highly effective few-layer MoS₂ catalyst using a two-step method involving liquid-phase exfoliation assisted by surfactants such as Sodium Dodecyl Sulfate (SDS) and Cetyltrimethylammonium Bromide (CTAB) and followed by hydrothermal reaction for the overall water splitting. Morphological, structural, and chemical characterizations confirmed the reduction in the number of layers and increased bandgap of MoS₂-SDS through liquid phase exfoliation. Further, the effect of the surfactants on the electrocatalytic water splitting performance was evaluated, and it was found that SDS surfactant aided MoS₂ (MoS₂-SDS) demonstrated exceptional performance for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The electrodes demonstrated low overpotentials for the hydrogen evolution reaction (HER η₁₀ = 125 mV) and oxygen evolution reaction (OER η₁₀ = 213 mV), accompanied by a high surface area, significantly low charge transfer resistance, and electrochemical durability for over 20 h. In addition, overall water splitting performance was evaluated over 110 h with a Faradaic efficiency of over 90% and energy conversion efficiency of 60%. For a sustainable future, green hydrogen generated via renewable solar energy using few-layer MoS₂-SDS has emerged as a highly promising alternative to noble metal-based catalysts for practical electrocatalytic alkaline water splitting.