Accumulated charge density at the interface boosts the urea oxidation reaction activity of Ni3N/Ni3S2 heterointerface.

[Display omitted] • Ni 3 N (1 1 0)/Ni 3 S 2 (0 1 0) heterointerface was successfully synthesized via the nitridation of β -Ni(OH) 2 by urea. • Accumulated charge density and enhanced DOS lower the reaction barriers of the rate-controlling step of *CONHN to *CONN. • The cooperation of nickel moieties at the heterointerface results in the superb intrinsic UOR activity. • Ni 3 N (1 1 0)/Ni 3 S 2 (0 1 0) heterointerface exhibits superior UOR activity, selectivity and durability. Optimizing the adsorption strength of multiple intermediates at one single active site at the same time is rather difficult. Heterointerface engineering provides more than one type of active sites to function, which may dramatically enhance the intrinsic urea oxidation reaction (UOR) activity of catalysts. Herein, a Ni 3 N (1 1 0)/Ni 3 S 2 (0 1 0) heterointerface was fabricated. The electronic interactions between the two phases generates an accumulated charge density heterointerface and endows the heterointerface with more enhanced density of states, which facilitates the adsorption and desorption of more UOR intermediates, thus lowering the theoretical reaction barrier for the rate-controlling step of *CONHN to *CONN. The nickel moieties on Ni 3 N side tends to bond carbonyl and the nickel moieties on Ni 3 S 2 side preferentially bond amnio. The cooperation of both nickel moieties contributes to the superb intrinsic UOR activity of Ni 3 N (1 1 0)/Ni 3 S 2 (0 1 0) heterointerface. As a consequence, Ni 3 N (1 1 0)/Ni 3 S 2 (0 1 0) heterointerface showcases outstanding UOR activity, reaching 105.66 mA·cm−2 at 1.6 V. This work provides an excellent UOR catalyst and helps to better understand the cooperation mechanism of the active sites at the heterointerface. [ABSTRACT FROM AUTHOR]