High-performance self-supporting AgCoPO₄/CFP for hydrogen evolution reaction under alkaline conditions

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Electrochemical water splitting is key for renewable energy storage.
• Developing efficient, low-cost, and stable catalysts for the hydrogen evolution reaction (HER) in alkaline media is crucial.

Purpose of the Study:

• To synthesize and evaluate a novel self-supporting AgCoPO4/CFP catalyst for enhanced HER performance.
• To investigate the catalyst's activity for urea oxidation reaction (UOR) to reduce overall water splitting energy requirements.

Main Methods:

• A simple hydrothermal method was used to prepare a AgCo(CO)4 precursor on carbon fiber paper (CFP).
• Thermal phosphorization was employed to obtain the AgCoPO4/CFP catalyst.
• Electrochemical testing was performed to assess HER and UOR catalytic activity.

Main Results:

• The AgCoPO4/CFP catalyst exhibited excellent HER performance in alkaline conditions with an overpotential of 32 mV at 10 mA cm-2 and a Tafel slope of 34.4 mV dec-1.
• The catalyst demonstrated outstanding UOR activity, requiring only 1.45 V at 10 mA cm-2 with 0.5 M urea addition for overall water splitting.
• The enhanced performance is attributed to the catalyst's hydrophilic surface and the synergistic effect between Ag and Co metals.

Conclusions:

• The AgCoPO4/CFP catalyst is a highly efficient electrocatalyst for HER in alkaline media.
• The catalyst's ability to facilitate UOR offers a pathway to lower the energy demand for overall water splitting.
• This work presents a new strategy for designing and synthesizing advanced electrocatalysts for hydrogen production.