Pt/α-MoC Catalyst Boosting pH-Universal Hydrogen Evolution Reaction at High Current Densities.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Efficient hydrogen evolution reaction (HER) electrocatalysts are crucial for industrial water electrolysis and green hydrogen production.
• Developing pH-universal catalysts that operate effectively at high current densities remains a significant challenge.

Purpose of the Study:

• To construct and evaluate a subnanometric Pt/α-MoC electrocatalyst for pH-universal hydrogen evolution reaction (HER).
• To investigate the synergistic mechanism between Pt and α-MoC for enhanced HER performance at high current densities.

Main Methods:

• Synthesis of subnanometric Pt/α-MoC electrocatalyst.
• Electrochemical characterization of HER performance in all-pH electrolytes.
• Quasi-in situ X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations.

Main Results:

• Pt/α-MoC exhibits excellent HER performance, achieving a current density of 1000 mA cm^-2 at a low overpotential of 125 mV.
• The catalyst demonstrates efficient water dissociation by α-MoC and favorable proton desorption kinetics on Pt sites.
• A proton exchange membrane water electrolysis device using Pt/α-MoC showed low cell voltage (1.65 V at 1 A cm^-2) and stability over 300 hours.

Conclusions:

• The synergistic effect between α-MoC and atomically dispersed Pt enables highly efficient HER, particularly at high current densities.
• Pt/α-MoC is a promising, scalable electrocatalyst for industrial green hydrogen production.
• This study provides valuable insights for designing advanced electrocatalysts for high-performance water electrolysis.