Surface hydroxyl enriched ruthenium selenide nanoparticles for efficient seawater hydrogen evolution reaction

The rationally designed ruthenium selenide (RuSe1.6-500) nanocomposite with selenium vacancies was synthesized via a hydrothermal/annealing approach. During the annealing step, calcination under a H2/Ar atmosphere facilitated the evaporation of selenium, thereby generating selenium vacancies. This study confirmed that RuSe1.6-500 prepared by this method functions as an efficient electrocatalyst for the hydrogen evolution reaction (HER) in seawater. Furthermore, experiments and density functional theory calculations demonstrated that the enhanced electrocatalytic performance and resistance to Cl-induced corrosion in seawater can be attributed to the surface reconstruction of RuSe1.6-500 during the HER process. Specifically, the reconstruction involves the adsorption of hydroxyl groups at selenium vacancies, leading to the formation of a hydroxy-rich surface on RuSe1.6-500. The hydroxy-rich surface is responsible for the superior electrocatalytic activity and stability of RuSe1.6-500 as an electrocatalyst for the HER in seawater.