Phase-dependent electrocatalytic nitrate reduction to ammonia on Janus Cu@Ni tandem catalyst

Lou, Yao-Yin, Zheng, Qi-Zheng, Zhou, Shi-Yuan, Fang, Jia-Yi, Akdim, Ouardia, Ding, Xing-Yu, Oh, Rena, Park, Gyeong-Su, Huang, Xiaoyang and Sun, Shi-Gang 2024. Phase-dependent electrocatalytic nitrate reduction to ammonia on Janus Cu@Ni tandem catalyst. ACS Catalysis 14 , 5098–5108. 10.1021/acscatal.4c00479

Preview

PDF - Published Version Available under License Creative Commons Attribution. Download (5MB) | Preview

Abstract

Electrosynthesis of NH3 from nitrate anion (NO3–) reduction (NO3–RR) is a cascade reaction, which is considered a great potential alternative to the Haber–Bosch route to reduce CO2 emissions and alleviate the adverse effects of excessive NO3– contamination in the environment. Frequently, solid solution alloys (SSAs) with a single-phase active site may struggle to fully utilize their benefits during the entire process of nitrate (NO3–) reduction, which involves multiple intermediate reactions. In this study, we showed that by separating Cu and Ni in a Janus Cu@Ni catalyst structure, we can achieve high performance in NO3–RR, yielding a high Faradaic efficiency (92.5%) and a production rate of NH3 (1127 mmol h–1 g–1) at −0.2 V versus RHE, compared to CuNi SSA (82.6%, 264 mmol h–1 g–1). Here, we demonstrate that a Janus Cu@Ni catalyst with short-range ordered catalytic sites favors the adsorption of NO through a bridge-bond mode. Simultaneously, a hydrogen spillover process was observed, in which Ni dissociates H2O to generate *H which spontaneously migrates to adjacent catalytic sites to hydrogenate the *NOx intermediates. This facilitates N–O bond cleavage, resulting in the NH3 production rate nearly 5 times higher than that of CuNi SSA, where NO was linearly bonded on its surface. The study of this catalytic effect, a cooperative tandem enhancement, provides insights into the design of multifunctional heterogeneous catalysts for electrochemical NH3 synthesis.

Item Type:	Article
Date Type:	Published Online
Status:	Published
Schools:	Chemistry Cardiff Catalysis Institute (CCI)
Publisher:	American Chemical Society
ISSN:	2155-5435
Funders:	National Natural Science Foundation of China (NSFC)
Date of First Compliant Deposit:	22 March 2024
Date of Acceptance:	4 March 2024
Last Modified:	28 Mar 2024 10:45
URI:	https://orca.cardiff.ac.uk/id/eprint/167478

Actions (repository staff only)

Edit Item