Abstract
Significant efforts have been made to develop highly active non-noble metal-based, affordable metallic and stable electro-catalysts for hydrogen evolution reaction (HER). Strong acid and bases are now used in HER operations to achieve large-scale, sustained H2 fuel production. However, few studies have utilized phosphate-buffered neutral electrolytes (PBS) in the field of neutral electrolyte technology. In this work, a certain alloys with a Ni–Cr basis have been produced as favorable components for the HER under neutral conditions. Additionally, the current investigations are emphasizing on the concentration of buffer phosphate species in the HER activity of various materials. By employing polarization and electrochemical impedance spectroscopy (EIS) in neutral solutions, the electro-catalytic activity of new alloys on HER was evaluated. According to the preliminary findings, the examined Ni–Cr-based alloys show superior HER catalytic activity in neutral electrolytes. Additionally, the Ni–Cr alloy matrix with Fe and Mo added enhances HER electrocatalytic efficiency while lowering interfacial charge transfer resistance. Due to its low overpotential of −297 mV @ 10 mA cm−2 and Tafel slope of 94 mV dec−1 in 1.0 M PBS media, the Ni–Cr–Mo–Fe alloy exhibits an efficient HER, suggesting that the Ni–Cr–Mo–Fe electrode will be a potential noble metal-free electro-catalyst for HER. The Ni–Cr–Mo–Fe cathode is a readily available and affordable material for the production of HER in neutral medium.
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•Ni–Cr-based alloys exhibits remarkable HER with low Tafel slopes and lower overpotential.•The Ni–Cr–Mo–Fe alloy exhibited high HER in 1.0 M PBS solution.•An overpotential of 297 mV vs RHE is sufficient to deliver 10 mA cm−2 from neutral water.•HER on the Ni–Cr-based alloys is conducted by Volmer–Heyrovsky mechanism.•This research provides new and efficient non-precious catalysts for HER.