Three-dimensional carbon network-supported black phosphorus-cobalt heterojunctions: An efficient electrocatalyst for...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Black phosphorus (BP) is a 2D material with promising electrocatalytic properties.
• However, BP's poor stability in oxygen/water environments limits its application.
• Developing stable BP-based electrocatalysts is crucial.

Purpose of the Study:

• To synthesize and characterize BP-Co heterojunctions on a CNT@NC support for enhanced electrocatalysis.
• To investigate the effect of the BP-Co Schottky junction on BP's stability and electronic properties.
• To evaluate the oxygen evolution reaction (OER) performance of the novel catalyst.

Main Methods:

• Synthesis of BP-Co/CNT@NC via pyrolysis of ZnCo-zeolitic imidazolate frameworks and solvothermal treatment.
• Characterization of the material's structure and electronic properties.
• Density functional theory (DFT) calculations to analyze interfacial electron transfer and band structure.
• Electrocatalytic testing for OER performance, including overpotential, Tafel slope, and long-term stability.

Main Results:

• The BP-Co Schottky junction significantly improved BP's stability and conductivity.
• DFT calculations confirmed electron redistribution and a strong built-in field at the BP-Co interface.
• The optimized BP-Co/CNT@NC catalyst demonstrated superior OER performance with a low overpotential (370 mV at 100 mA/cm²) and a Tafel slope of 40 mV/dec.
• Excellent OER performance was observed at high current densities (100-400 mA/cm²).

Conclusions:

• The developed BP-Co/CNT@NC heterojunction effectively enhances the stability and electrocatalytic activity of black phosphorus.
• This strategy provides a pathway for utilizing BP-based materials in demanding electrocatalytic applications.
• The improved OER performance highlights the potential of Schottky junctions in catalyst design.