Rational synthesis of Au3Cu@Rhx core–shell aerogel electrocatalysts for efficient hydrogen evolution reaction

Alkaline water electrolysis is a promising technology for generating green hydrogen from renewable electricity. However, this process is hindered by high energy barriers associated with intermediate desorption, which limits overall efficiency. Herein, we report the rational synthesis of defect-rich Au 3 Cu@Rh aerogels as high-performance electrocatalysts for the hydrogen evolution reaction (HER) under alkaline conditions. Comprehensive material characterization combined with density functional theory (DFT) calculations reveal the pivotal role of defect-rich structure in boosting catalytic activity. Owing to the abundant crystallographic defects at the atomic-level and a well-defined core–shell heterointerface, the optimized Au 3 Cu@Rh 3 aerogel exhibits exceptional HER performance, requiring an overpotential of merely 51.5 mV to deliver a current density of 10 mA cm −2 . This work provides a novel synthesis strategy and demonstrates its broad potential for the tailored fabrication of multicomponent core–shell aerogels with superior electrocatalytic properties. Graphical abstract