Interfacial Synergy of Ultralong Jagged Pt85Mo15-S Nanowires with Abundant Active Sites on Enhanced Hydrogen Evolution in Alkaline Solution

Higher electrocatalytic activity of hydrogen evolution in basic media on Pt based catalysts is largely dependent on the intrinsic microscopic surface chemical environment. Given the fundamental mechanism of interfacial interaction between Pt and oxophilic components, engineering a moderate oxygen-friendly surface environment of Pt based catalysts is beneficial to endowing Pt with a high catalytic activity of hydrogen evolution reaction (HER). Herein, we fabricated a ultralong jagged Pt85Mo15-S nanowires with rich interfacial active sites by using S as “active auxiliary” to demonstrate the enhanced catalytic HER performance. Strikingly, the Pt85Mo15-S nanowires exhibit an exceptional activity with 3.62 times specific current density and 4.03 times mass current density higher than those of commercial Pt/C, as well as excellent stability towards alkaline HER. The X-ray photoelectron spectroscopy reveals that S element could prevent the further oxidization of Mo, and then leading enough electron transfer from Mo to Pt. In addition, the theoretical calculations demonstrate that the water dissociation energy barrier can be significantly reduced under the interfacial synergy of intimate contact between Pt and MoSx. This work illustrates a new strategy to advance fundamental exploration on electrocatalytic materials, which makes a systematic approach to build the interfacial model catalyst available for fundamental electrocatalytic studies of alkaline HER.