Low‐Pt Bifunctional Electrode for Durable and Efficient Hydrogen Production via Hexamethylenediamine‐Assisted Water Electrolysis

Abstract The efficiency of water electrolysis for hydrogen production is significantly hindered by the slow kinetics of the oxygen evolution reaction (OER), posing challenges for its industrial application. Herein, a Pt/Ni(OH) 2 self‐supported electrode with a Pt loading as low as 0.036 mg·cm −2 is synthesized via a one‐step sodium dodecyl sulfate assisted anodization coupled with electrodeposition method. The electrode exhibits superior performances for both the hydrogen evolution reaction (HER) and the electrooxidation of hexamethylenediamine (HMDAOR) compared to commercially available 20% Pt/C in both acidic and alkaline systems. Notably, it can be operated continuously over 600 h at an industrial grade current densities of 1400 and 1000 mA·cm −2 in acidic and alkaline electrolytes, respectively, demonstrating its outstanding long‐term stability. It can achieve a current density of 1000 mA·cm −2 for hydrogen production at a cell voltage of 1.561 V in HMDA‐assisted water electrolysis, demonstrating its practical application in water electrolysis. The enhanced performance can be attributed to the Ni‐induced modulation of the Pt electronic structure, strong Pt‐support interaction enhanced the intrinsic activity of Pt, and synergistic effects between Pt and Ni. These provide valuable insights to design advanced catalysts for water electrolysis, and to broad their application in hydrogen production and wastewater treatment areas.