Pd Single Atoms/Clusters at the Oxygen Defect-Rich WOx_C Nanowire Structure Facilitate H* Adsorption and Desorption for Efficient and Stable Hydrogen Evolution Reaction

The development of low-cost, highly active, and stable catalysts for hydrogen production from electrolyzed water is imminent. Herein, a Pd single-atom/clusters catalyst based on an oxygen-rich defective WOx_C nanowire mesh structure was successfully designed. The prepared Pd1.54/WOx_C 1:1 catalyst exhibits HER activity (overpotential of 19 mV to RHE at 10 mA cm–2) and stability (The current loss of Pd1.54/WOx_C 1:1 is negligible after 10,000 cycles or 24 h of chronoamperometry test at 200 mA cm–2). The introduction of atomic Pd species further increased the oxygen defect concentration in the catalyst, which, in turn, aided the anchoring and dispersion of atomic Pd species. In addition, in situ Raman spectra and theoretical calculations show that the introduction of oxygen-rich defects and Pd single-atom/cluster sites helps promote H* adsorption and desorption and further lowers the energy barrier of the whole HER process. This study provides an idea of commercial hydrogen production from electrolyzed water.