Efficiently Synergistic Hydrogen Evolution Realized by Trace Amount of Pt-Decorated Defect-Rich SnS₂ Nanosheets

The electrocatalytic hydrogen evolution reaction (HER) has attracted increasing attention in the field of hydrogen-based economy, whereat developing cheap and efficient catalysts to reduce the use of Pt-based catalysts is highly required. Tin disulfide (SnS 2 ) as a new rising star has exhibited intriguing properties in energy storage and conversion applications, while showing slow progress in HER due to the inherent poor activity. Herein, we demonstrate the successful structural engineering and simultaneous integration of trace amount Pt in SnS 2 nanosheets via a facile and effective in situ cycling voltammetry activation process, leading to the efficiently synergistic HER. Defect-rich SnS 2 nanosheets decorated with a trace amount (0.37 wt %) of Pt exhibit greatly enhanced HER activity due to the synergy between them, revealing low onset potential of 32 mV and overpotential of 117 mV at 10 mA/cm 2, small Tafel slope of 69 mV/dec, and large exchange current density of 394.46 μA/cm 2 . Present work provides an intriguing strategy for developing ultralow loading Pt electrocatalysts with high HER performance.