Alloy/strain engineering of Pt-based nanowires with controllable electronic structures towards boosted water electrolysis catalysis

Abstract

Low-dimensional platinum-based catalysts have aroused tremendous interest in electrocatalysis, benefiting from their high specific activity and novel electronic structures. Nevertheless, the practical application has been hampered by their complex synthesis process and finitely exposed active sites. Herein, we report novel 1D Pt-based nanowires (NWs) with inner tensile strain, multiple catalytically active lattice steps, and controllable electronic structures, which can be yielded through a facile large-scale room temperature reduction method on the gram scale. The favored geometrical and electronic structures are beneficial to improve the specific activity of catalytic sites towards boosting the water electrolysis process. By simply doping the second element (Ir or Ru) and inducing a tensile strain, the hydrogen evolution reaction (HER) can be substantially accelerated. In particular, PtIr-300 NWs/C showed an ultra-low overpotential of −9 mV and −18 mV at a current density of 10 mA cm⁻² and 100 mA cm⁻². Additionally, PtIr-300 NWs/C attained 17.1-fold and 49.3-fold enhancement for the mass activity and intrinsic activity of HER recorded at 15 mV compared to Pt/C in 0.5 M H₂SO₄. This work paved a way to the design and construction of an efficient electrocatalyst.