Synergistic interface engineering and structural optimization of non-noble metal telluride-nitride electrocatalysts for sustainably overall seawater electrolysis

Searching for ideal candidates with high electrocatalytic performance for both HER and OER is a major objective to realize the large-scale H2 production by seawater electrolysis. Herein, we report delicate, heterostructured NiTe-NiCoN and NiTe-NiFeN electrocatalysts, which exhibit outstanding HER and OER performance, respectively. Impressively, the NiTe-NiCoN || NiTe-NiFeN couples in alkaline seawater solution delivered 400 mA cm−2 at 1.84 V along with long-term stability. Further analysis has revealed that not only heterogeneous interface engineering ensures exposure of abundant active sites and faster electron-mass transfer, but also induces electron modulation that optimizes the absorption/desorption for the reaction intermediates to enhanced the intrinsic activity. Notably, a high electric field intensity generated by the nanosheet-nanorod structure induces a local “hydroxide enrichment” environment that promotes the OER kinetics. This work shed lights on these novel heterostructured electrocatalysts with strong synergy, while demonstrating the key role of the unique nanostructures in high-efficiency seawater electrolysis. [Display omitted] •NiTe-NiCoN and NiTe-NiFeN with core-shell nanorod arrays ensure a high active area, good electrical conductivity and seawater corrosion resistance.•Electronic modulation to enhance the intrinsic activity is achieved through interfacial synergy between metal nitrides and nickel telluride.•The nanostructure-induced "hot spots" effect modulates the electric field state to promote seawater OER kinetics and suppress the side effects of chlorine.