Topological metal and noncentrosymmetric superconductor α-BiPd as an efficient candidate for the hydrogen evolution reaction

Abstract

Due to the metal hydride, Pd-based electrodes are not an ideal electrocatalyst for the hydrogen evolution reaction (HER), which is an important half-reaction of water splitting. Herein, we firstly propose to utilize topological metal and noncentrosymmetric superconductor α-BiPd in the HER process to reduce the metal hydride effect and systematically evaluate the catalyst properties by combining experimental measurements and first-principles calculations. It is demonstrated that bulk α-BiPd can be exfoliated into nanosheets with ∼5 nm thickness by liquid-phase exfoliation. The as-prepared α-BiPd nanosheets exhibit high performance with a low overpotential of 144 mV at −10 mA cm⁻² and a Tafel slope of 104.0 mV dec⁻¹, which is far superior to that of a Pd electrode. Besides, α-BiPd nanosheets show good stability over 13 h in chronoamperometry measurements. First-principles calculations also point out that ΔG is close to zero within 0.2 eV even at 0.5 ML coverage, indicating both good HER catalytic reactivity per site and large reactive surface coverage. Both experiments and theory indicate that α-BiPd nanosheets are a promising catalyst for energy conversion.