Highly
efficient electro-oxidation of benzylamine to generate value-added
chemicals coupled with the hydrogen evolution reaction (HER) is crucial
but challenging. Herein, targeted regulation of the electronic states
of Ni sites was realized via simple yet precise nitridation engineering.
Benefiting from the insertion of N atoms into the Ni lattice, the
Ni3N electrode exhibits superior activity, selectivity,
and stability for the benzylamine oxidation reaction (BOR). Especially,
under the industrially relevant current (∼250 mA), the Ni3N catalyst remains ∼95% selective for benzonitrile
production, reaching 1.43 mmol h–1 cm–2. Experimental and theoretical findings reveal that the formation
of Ni–N bonds upshifts the Ni d-band center and optimizes the
electrophilic properties of Ni sites, which contributes to the adsorption
and dehydrogenations process of benzylamine. Furthermore, due to the
work function difference between Ni and Ni3N, a strong
mutual interaction occurs at the heterogeneous interface for Ni-Ni3N, which endows it with the appropriate H* adsorption energy
and thus excellent HER performance. Impressively, the integrated solar-energy-driven
BOR coupled with the HER electrolyzer affords 10 mA cm–2 at an ultralow voltage of 1.4 V and exhibits a promising practical
application (ηsolar‑to‑hydrogen = 13.8%).
This work offers a new perspective for the bifunctional design of
nitrides in the field of electrosynthesis.