Atomic interactions of two-dimensional PtS2 quantum dots/TiC heterostructures for hydrogen evolution reaction

Two-dimensional quantum dots (2D QDs) comprising PtS2 with low Pt loading (0.002 wt.%) distributed on a distinctive CVD-grown titanium carbide substrate (PtS2/TiC) was successfully synthesized and employed for a hydrogen evolution reaction (HER). Notably, despite the low loading of the former component, PtS2/TiC showed excellent HER activity with a superior overpotential (55 mV at 10 mA/cm−2) to that of commercial Pt/C (50 mV at 10 mA/cm−2). The Faraday efficiency of PtS2/TiC was found to be 92.5 %, revealing the superior properties of hydrogen production. The In-situ Raman spectra reveal the important role of S atoms in PtS2 as the active sites for HER, as evidenced by SH bonding formation at 2532 cm-1 during the HER process. This study provides a fundamental understanding essential for the design of more efficient catalysts in the field of electrochemical applications.