Amorphous/Crystalline Heterojunction Engineered High-Density Strain in RuSeTe for Efficient Alkaline Hydrogen...

The efficiency and durability of electrocatalysts for the alkaline hydrogen evolution reaction (HER) are impeded by high overpotentials and sluggish kinetics, limiting their practical application. Here, we present a novel class of RuSeTe-based electrocatalysts featuring high-density tensile strain induced by amorphous/crystalline heterojunctions, where the strain distribution density is precisely regulated via interface length manipulation. Theoretical and experimental analyses reveal that the tensile strain optimizes the d-band center and water adsorption energy, significantly reducing the energy barrier of the Volmer step. The optimized RuSeTe catalyst achieves an ultralow overpotential of 20 mV at 10 mA cm^{- 2} and a Tafel slope of 33 mV dec^{- 1} in alkaline media, outperforming state-of-the-art Ru-based chalcogenides. Furthermore, the catalyst exhibits sustained durability for 1100 h (>45 days) at a current density of 100 mA cm^-2, maintaining a nearly constant potential throughout the test. This work proposes a universal strategy for inducing high-density strain through amorphous/crystalline heterointerface engineering, offering new insights into designing efficient and stable HER catalysts.