Bi nanodendrites for highly efficient electrocatalytic NO reduction to NH3 at ambient conditions

Electrocatalytic NO reduction into value-added NH3 addresses the need for NO emission abatement and presents a sustainable alternative to the industrial Haber-Bosch process. It is however challenged by unsatisfactory conversion efficiencies due to competitive hydrogen evolution and requires highly active and selective catalysts for NO reduction reaction (NORR). In this work, we report the Bi nanodendrites (Bi NDs) with sufficient exposure of catalytic sites act as a high-efficiency NORR electrocatalyst toward selective NH3 synthesis. This catalyst attains a remarkable NH3 yield of 1194 mu g h(-1) mg(cat)(-1). and a Faradaic efficiency as high as 89.2% in neutral media, making it one of the most promising aqueous-based NORR catalysts for NO-to-NH3 conversion. Additionally, we coupled Bi NDs-loaded carbon paper into an aqueous Zn-NO battery with a Zn plate anode to provide a peak power density of 2.33 mW cm(-2) and an NH3 yield of up to 84.4 mu g h(-1) cm(-2). NO reduction mechanism on the Bi (012) surface is further revealed and discussed with theoretical calculations. (C) 2022 Elsevier Ltd. All rights reserved.

Automated summary

This study reports a highly efficient electrocatalyst for the selective reduction of NO to NH3. The catalyst exhibits high NH3 yield and Faradaic efficiency in neutral media, making it a promising catalyst for aqueous-based NO-to-NH3 conversion.