Ambient γ-Rays-Mediated Noble-Metal Deposition on Defect-Rich Manganese Oxide for Glycerol-Assisted H₂ Evolution at...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient electrocatalysts is key for energy-saving hydrogen production.
• Novel synthesis methods are needed to create advanced bifunctional electrocatalysts.

Purpose of the Study:

• To report a novel ambient and controllable gamma-ray radiation reduction method for synthesizing noble metal nanoparticles on defect-rich manganese oxides (M@MnO_2-x).
• To investigate the efficacy of these M@MnO_2-x electrocatalysts for glycerol-assisted hydrogen (H₂) evolution.

Main Methods:

• Synthesis of M@MnO_2-x (M=Ru, Pt, Pd, Ir) nanoparticles anchored on defect-rich manganese oxides using gamma-ray radiation reduction.
• Electrochemical performance evaluation for glycerol-assisted H₂ evolution in a continuous-flow electrolyzer.
• In situ spectroscopic analysis and theoretical calculations to elucidate reaction mechanisms.

Main Results:

• Gamma-ray reduction simultaneously formed nanoparticles and defect supports bridged by stable metal-oxygen bonds.
• Ru@MnO_2-x exhibited excellent performance, achieving 0.5 A cm^-2 at a low cell voltage of 1.68 V with remarkable stability.
• Interfacial Ru-O-Mn bonds activated catalytic sites, balancing glycerol and OH* adsorption and promoting H₂O dissociation and hydrogen desorption.

Conclusions:

• The gamma-ray radiation reduction is an effective method for synthesizing stable, high-performance bifunctional electrocatalysts.
• The defect-rich MnO₂ support and defect-regulated Ru sites synergistically enhance glycerol-assisted hydrogen production.
• This approach offers a promising pathway for energy-saving hydrogen generation.