Intensifying Interfacial Reverse Hydrogen Spillover for Boosted Electrocatalytic Nitrate Reduction to Ammonia
Xiao Ouyang, Wei Qiao, Yuting Yang, Baojuan Xi, Yu Yu, Yilu Wu, Jingyun Fang, Ping Li, Shenglin Xiong
Abstract
Abstract Rational regulation of active hydrogen (*H) behavior is crucial for advancing electrocatalytic nitrate reduction reaction (NO 3 RR) to ammonia (NH 3 ), yet in‐depth understanding of the *H generation, transfer, and utilization remains ambiguous, and explorations for *H dynamic optimization are urgently needed. Herein we engineer a Ni 3 N nanosheet array intimately decorated with Cu nanoclusters (NF/Ni 3 N−Cu) for remarkably boosted NO 3 RR. From comprehensive experimental and theoretical investigations, the Ni 3 N moieties favors water dissociation to generate *H, and then *H can rapidly transfer to the Cu via unique reverse hydrogen spillover mediating interfacial Ni−N−Cu bridge bond, thus increasing *H coverage on the Cu site for subsequent deoxygenation/hydrogenation. More impressively, such intriguing reverse hydrogen spillover effect can be further strengthened via elegant engineering of the Ni 3 N/Cu heterointerface with more intimate contact. Consequently, the NF/Ni 3 N−Cu with Cu nanoclusters intimate anchoring presents record NH 3 yield rate of 1.19 mmol h −1 cm −2 and Faradaic efficiency of 98.7 % at −0.3 V vs. RHE, being on par with the state‐of‐the‐art ones. Additionally, with NF/Ni 3 N−Cu as the cathode, a high‐performing Zn−NO 3 − battery can be assembled. This contribution illuminates a novel pathway to optimize *H behavior via distinct reverse hydrogen spillover for promoted NO 3 RR and other hydrogenation reactions.