Work

In-situ reconstruction of Ni-modulated BiO 2− x for boosting electrocatalytic nitrite reduction to ammonia

Year: 2025

Type: article

Abstract: Electrocatalytic nitrite reduction reaction (NO2−RR) to synthesize ammonia (NH3) has been constrained by sluggish kinetics of water dissociation and the weak adsorption of nitrite. In this work, we develop an in-situ reconstruction strategy that transforms Ni-doped BiO2-x (NiBiO2-x) to Bi/NiBiO2-x, which exhibits excellent activity and selectivity for NO2−RR to synthesize NH3. Diverse ex-situ and in-situ characterizations reveal potential-driven structural transformation from NiBiO2-x to Bi/NiBiO2-x, which features dual Ni2+-Bi0 active sites. The Ni2+ site is able to reduce the water dissociation barrier from 0.79 to 0.41 eV, while concurrently the Bi0 site can strengthen NO2− adsorption to promote *NO2H intermediate formation. Consequently, the in-situ constructed Bi/NiBiO2-x catalyst with Ni2+-Bi0 catalytic pairs enable an excellent NO2−RR performance, achieving a NH3 Faradaic eﬃciency (FENH3) of 94.5% at −0.6 V vs. RHE. The present study opens the new direction to in-situ construct high-performance electroreduction catalysts for small molecule synthesis.

Source: Nano Research

DOI: 10.26599/nr.2025.94908176