Cation vacancy-modulated PtPdRuTe five-fold twinned nanomaterial for catalyzing hydrogen evolution reaction

The hydrogen evolution reaction (HER) is an ideal model to explore the effect between the activity and the surface vacancy of catalysts. Compared to the anion vacancy, the cation vacancy is more challenging to selectively generate due to the large formation energy, and the serious lack of insight into the structure-activity relationship of cation vacancy-rich catalysts. Herein, we report a facile solid-liquid phase chemical strategy for in situ formation of cation vacancies in a five-fold twinned PtPdRuTe anisotropic structure (v-Pd3Pt29Ru62Te6 AS). Five-fold twinned AS with metal vacancies preferentially produced is confirmed by both X-ray photoelectron spectroscopy (XPS) and high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM). Due to the synergy of metal vacancies and twinned structural advantages, including the appropriate hydrogen binding energy, large exposed surface, anisotropic structure and fast mass/charge transport, v-Pd3Pt29Ru62Te6 AS exhibits significantly enhanced HER electrocatalytic performance in both alkaline and acidic solutions, with ultrasmall overpotentials of 22 and 39 mV to achieve 10 mA cm−2, respectively, and remarkable long-term stability (at least 30 h). These results herald a promising strategy to utilize defective twinned materials for advanced energy storage applications.