Metal telluride-nitride electrocatalysts for sustainably overall seawater electrolysis

Abstract

High-efficiency alkaline seawater electrolysis is a promising strategy to promote the sustainability of wide-ranging hydrogen (H2) production, and the global goal of carbon neutrality. Searching for an ideal candidate with low cost and high electrocatalytic performance for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) is a major objective. Herein, we report delicate, heterostuctured NiTe-NiCoN and NiTe-NiFeN electrocatalysts constructed of nickel cobalt nitride and nickel iron nitride nanosheets uniformly anchored on NiTe nanorod arrays, respectively, which ensure outstanding HER and OER activity along with ultra-long-term stability. Impressively, the NiTe-NiCoN || NiTe-NiFeN couples in alkaline seawater solution delivered 500 mA cm−2 at a record low voltage of 1.84 V, and realized an industry-level performance via a solar-powered system and a wind-power system. Further comprehensive analysis has revealed that interface engineering strategy not only ensures that the surficial nitride exposes abundant active sites, but also induces electron modulation that optimizes the binding strength of absorption/desorption for the reaction intermediates to enhanced the the intrinsic activity, as well as facilitate faster electron-mass transfer. Notably, a high electric field intensity generated by the unique nanosheet-nanorod structure induces a local “hydroxide enrichment” environment that effectively promotes the OER kinetics, while inhibits the side effects of chlorine. 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.