Electronically modulated nickel boron by CeO doping as a highly efficient electrocatalyst towards overall water...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing efficient, durable, and economical non-noble metal electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) remains a significant challenge.
• Bifunctional catalysts that can perform both HER and OER are crucial for efficient water splitting.

Purpose of the Study:

• To explore the strategy of doping metal borides with rare earth metal oxides to create highly efficient bifunctional electrocatalysts.
• To develop a novel CeO2-doped NiB catalyst supported on nickel foam (CeO2-NiB@NF) for enhanced electrocatalytic activity and stability.

Main Methods:

• Fabrication of the CeO2-NiB@NF electrocatalyst using a one-step mild electroless plating reaction.
• Electrochemical characterization of the catalyst for HER and OER performance, including overpotential measurements.
• Testing of the catalyst in a two-electrode electrolyzer for overall water splitting and stability assessment.

Main Results:

• The CeO2-NiB@NF electrode achieved a current density of 10 mA cm-2 at low overpotentials of 19 mV for HER and 274 mV for OER.
• A two-electrode electrolyzer using CeO2-NiB@NF required only 1.424 V to achieve 10 mA cm-2 for overall water splitting, surpassing commercial Pt-C/NF∥IrO2/NF.
• The catalyst exhibited good stability, operating for 100 hours at 10 mA cm-2, and demonstrated industrial-grade current density.

Conclusions:

• The CeO2-NiB@NF catalyst presents a highly efficient and durable bifunctional electrocatalyst for water splitting.
• Doping metal borides with rare earth metal oxides offers a promising new avenue for developing advanced non-precious metal catalysts.
• This research provides a novel strategy for the design of cost-effective and high-performance electrocatalysts for energy conversion applications.