Modulating amorphous/crystalline heterogeneous interface in RuCoMoyOx grown on nickel foam to achieve efficient overall water splitting

Abstract

Due to the vast difference in structure and the unique electronic state at the heterointerface, the amorphous/crystalline (a/c) heterostructure exhibits excellent potential in electrocatalysis. However, there are great challenges in constructing the material with ample a/c-heterointerfaces and controllably modulated a/c-heterointerface region through a simple one-step method. Herein, the a/c-RuCoMoyOx/NF (nickel foam) electrocatalyst is synthesized by the coprecipitation-microwave treatment method. Notably, microwave time directly affects the ratio of amorphous region (RuCoMoOx) to crystalline region (CoMoO4 and CoO). Surprisingly, the a/c-RuCoMoyOx/NF with abundant crystallinity/amorphous heterointerfaces exhibits the ultralow η10 values of 39 and 166 mV for HER and OER, which are 0.5-fold and 0.63-fold lower than that of Pt/C-NF and RuO2-NF benchmarks, respectively. Overall, this work provides a novel idea and convenient method for the construction of amorphous/crystalline heterointerfaces with modulated interface region, and guides the direction for the preparation of superior electrocatalysts by regulating the a/c-heterointerface region.