High-efficiency electrocatalytic nitrite reduction toward ammonia synthesis on CoP@TiO₂ nanoribbon array

Area of Science:

• Materials Science
• Electrochemistry
• Environmental Science

Background:

• Nitrite (NO2-) is an environmental contaminant requiring removal.
• Electrochemical reduction offers a sustainable route for ammonia (NH3) production.
• Highly efficient electrocatalysts are crucial for selective NO2- to NH3 conversion.

Purpose of the Study:

• To develop and evaluate a novel electrocatalyst for selective nitrite reduction to ammonia.
• To investigate the performance of CoP nanoparticle-decorated TiO2 nanoribbon arrays (CoP@TiO2/TP) for this application.
• To assess the potential of this system in a practical energy storage device.

Main Methods:

• Synthesis of CoP nanoparticle-decorated TiO2 nanoribbon arrays on a Ti plate (CoP@TiO2/TP).
• Electrochemical characterization of the CoP@TiO2/TP electrode for nitrite reduction in NaOH.
• Fabrication and testing of a Zn-NO2- battery utilizing the developed electrocatalyst.

Main Results:

• The CoP@TiO2/TP electrode exhibited a high NH3 yield (849.57 μmol h-1 cm-2) and Faradaic efficiency (97.01%).
• The electrocatalyst demonstrated good stability during nitrite reduction.
• A Zn-NO2- battery achieved a power density of 1.24 mW cm-2 and produced NH3.

Conclusions:

• CoP@TiO2/TP is a highly efficient electrocatalyst for selective nitrite to ammonia conversion.
• The developed material shows promise for both environmental remediation and sustainable ammonia synthesis.
• The integration into a Zn-NO2- battery highlights its potential for practical applications.