Engineering active sites on hierarchical transition bimetal oxides/sulfides heterostructure array enabling robust overall water splitting
Panlong Zhai, Yanxue Zhang, Yunzhen Wu, Junfeng Gao, Bo Zhang, Shuyan Cao, Yanting Zhang, Zhuwei Li, Licheng Sun, Jungang Hou
Abstract
Abstract Rational design of the catalysts is impressive for sustainable energy conversion. However, there is a grand challenge to engineer active sites at the interface. Herein, hierarchical transition bimetal oxides/sulfides heterostructure arrays interacting two-dimensional MoO x /MoS 2 nanosheets attached to one-dimensional NiO x /Ni 3 S 2 nanorods were fabricated by oxidation/hydrogenation-induced surface reconfiguration strategy. The NiMoO x /NiMoS heterostructure array exhibits the overpotentials of 38 mV for hydrogen evolution and 186 mV for oxygen evolution at 10 mA cm −2 , even surviving at a large current density of 500 mA cm −2 with long-term stability. Due to optimized adsorption energies and accelerated water splitting kinetics by theory calculations, the assembled two-electrode cell delivers the industrially relevant current densities of 500 and 1000 mA cm −2 at record low cell voltages of 1.60 and 1.66 V with excellent durability. This research provides a promising avenue to enhance the electrocatalytic performance of the catalysts by engineering interfacial active sites toward large-scale water splitting.