Long-term stability is a crucial performance indicator for HER catalysts, particularly in acidic environments. The durability of the optimized TC-3 catalyst was evaluated by conducting stability tests at a high current density of 4 A/cm 2 . Remarkably, the TC-3 catalyst demonstrates exceptional stability, maintaining a constant potential over an extended period of continuous electrolysis exceeding 150 hours (> 6 days), as evident from Fig. . The exceptional performance of TC-3 (e.g., long-term stability and low overpotential) at an ultrahigh current density of 4 A/cm 2 stands among the best electrocatalysts reported in prior work for acidic HER (Table ) . The outstanding stability of the TC-3 catalyst can be attributed to the inherent corrosion resistance of tungsten carbides and the strong bonding between tungsten carbide and the substrate formed during the synthesis process.