FeNi LDH/V₂CT_x/NF as Self-Supported Bifunctional Electrocatalyst for Highly Effective Overall Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Developing efficient bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) remains a significant challenge.
• Hierarchical nanostructures with strong interfacial interactions are crucial for enhancing electrocatalytic activity and stability.

Purpose of the Study:

• To synthesize a self-supported bifunctional electrode using FeNi layered double hydroxide (LDH) on V2CTx/nickel foam (NF).
• To investigate the enhanced electrocatalytic performance for OER and HER due to improved conductivity and exposed active sites.

Main Methods:

• Fabrication of FeNi LDH/V2CTx/NF electrode via hydrothermal deposition.
• Characterization of the electrode's structure, conductivity, and stability.
• Electrochemical testing in 1 M KOH for OER, HER, and overall water splitting.

Main Results:

• The FeNi LDH/V2CTx/NF electrode exhibited low overpotentials of 222 mV for OER and 151 mV for HER at 10 mA cm⁻².
• The nanohybrid structure prevented FeNi LDH aggregation, enhancing active site exposure and stability.
• Achieved a current density of 10 mA cm⁻² at 1.74 V for overall water splitting.

Conclusions:

• The FeNi LDH/V2CTx/NF electrode demonstrates excellent bifunctional electrocatalytic activity for water splitting.
• Simple synthesis strategies and structural engineering, including conductive substrates and hierarchical structures, can significantly improve electrocatalyst performance.