Unraveling Electron Transfer Dynamics in (Co-Mo)S Heterostructures for Sustainable Hydrogen Evolution

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Scalable synthesis of efficient electrocatalysts with sustained activity is crucial for practical water splitting.
• Developing advanced materials for hydrogen production is a key area in sustainable energy research.

Purpose of the Study:

• To report a confined mechanochemical strategy for ultrafast and scalable synthesis of mesoporous (Co-Mo)S heterostructures.
• To evaluate the bifunctional electrocatalytic performance and durability of the synthesized (Co-Mo)S catalyst for water splitting.

Main Methods:

• Confined mechanochemical synthesis of mesoporous (Co-Mo)S heterostructures.
• Electrochemical characterization including overpotential, Tafel slopes, Faradaic efficiency, and electrochemical impedance spectroscopy (EIS).
• Kinetic analysis using Arrhenius studies and trumpet plot analysis across varying pH.

Main Results:

• The optimized (Co-Mo)S catalyst delivered low overpotentials (150 mV for HER, 311 mV for OER) and minimal charge-transfer resistance (3.8 Ω).
• High Faradaic efficiencies (96% for HER, 98% for OER) and accelerated electron-transfer dynamics were observed.
• An alkaline electrolyzer using (Co-Mo)S achieved 10 mA cm⁻² at 1.58 V, demonstrating practical potential and robust durability.

Conclusions:

• Interfacial engineering in (Co-Mo)S heterostructures enhances charge transfer and catalytic kinetics.
• The confined mechanochemical strategy offers a scalable pathway for advanced electrocatalysts.
• The developed (Co-Mo)S catalyst shows significant promise for efficient and sustainable hydrogen production.