Hierarchical whisker-on-sheet NiCoP with adjustable surface structure for efficient hydrogen evolution reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Efficient hydrogen evolution reaction (HER) catalysts are crucial for renewable energy technologies.
• Developing novel electrocatalysts with enhanced activity and stability remains a key challenge.

Purpose of the Study:

• To synthesize hierarchical whisker-on-sheet (HWS) NiCoP anchored on Ni foam (NF) for efficient HER.
• To investigate the effect of surface structure and KOH activation on HER performance.

Main Methods:

• Controllable phosphidation of a hierarchical whisker-on-sheet Ni-Co-carbonates hydroxide precursor grown on Ni foam.
• Optimization of experimental parameters to control precursor formation and material microstructure.
• Electrochemical testing for hydrogen evolution reaction (HER) activity and performance evaluation before and after KOH activation.

Main Results:

• The synthesized HWS NiCoP/NF exhibited low overpotentials for HER (η10=59 mV, η100=220 mV).
• KOH surface activation dramatically enhanced HER performance (η10=42 mV, η100=141 mV).
• HWS NiCoP/NF outperformed other NiCoP morphologies, attributed to unique structure and hydrated metal formation post-treatment.

Conclusions:

• Hierarchical whisker-on-sheet NiCoP on Ni foam is a highly efficient electrocatalyst for HER.
• Surface activation via KOH treatment significantly improves catalytic activity.
• Tailoring material microstructure is a promising strategy for designing advanced HER catalysts.