1T-Phase molybdenum sulfide/cobalt oxide nanopillars hybrid nanostructure coupled with nitrogen-doped carbon thin-film as high efficiency electrocatalyst for oxygen evolution

Abstract

High efficient and durable catalysts are always needed to lower the kinetic barriers as well as prolong the service life associated with oxygen evolution reaction (OER). Herein, a sequential synthetic strategy is considered to prepare a hierarchical nanostructure, in which each component can be configured to achieve their full potential so that endows the resulting nanocatalyst a good overall performance. In order to realize this, well-organized cobalt oxide (Co3O4) nanopillars are firstly grown onto ultrathin 1T-molybdenum sulfide (1T-MoS2) to obtain high surface area electrocatalyst, providing electron transfer pathways and structural stability. After that, zeolitic imidazolate framework-67 (ZIF-67) derived carbonization film is further in situ deposited on the surface of nanopillars to generate plentiful active sites, thereby accelerating OER kinetics. Based on the combination of different components, the electron transfer capability, catalytic activity and durability are optimized and fully implemented. The obtained nanocatalyst (defined as 1T-MoS2/Co3O4/CN) exhibits the superior OER catalytic ability with the overpotential of 202 mV and Tafel slope of 57 mV·dec−1 at 10 mA·cm−2 in 0.1 M KOH, and good durability with a minor chronoamperometric decay of 9.15 % after 60,000 s of polarization.