Heteromorphic Zn0.76Co0.24S/Co3S4/NF as an efficient electrocatalyst to enhance hydrogen evolution reaction performance

Abstract

In order to design an efficient and stable non-noble metal hydrogen evolution catalyst, heteromorphic Zn0.76Co0.24S/Co3S4/NF catalyst was synthesized by hydrothermal vulcanization of ZnCo-LDH precursor. Meanwhile, by changing the curing time and the contents of Zn and Co precursors, a series of Zn0.76Co0.24S/Co3S4/NF catalysts with different proportions of bi-active components (Zn0.76Co0.24S and Co3S4) were obtained. In particular, the Zn0.76Co0.24S/Co3S4/NF-4 h (1:2) catalyst has a typical heterostructure and 3D nanosheet network structure. The nanosheets are composed of nanoparticles with an average size of 3.1 nm. More importantly, the Zn0.76Co0.24S/Co3S4/NF-4 h (1:2) catalyst shows a very low overpotential of 120 mV at a current density of 10 mA cm−2. Even, at the large current density of 200 mA cm−2, the Zn0.76Co0.24S/Co3S4/NF-4 h (1:2) catalyst only has the overpotential of 280 mV. Moreover, the overpotential of Zn0.76Co0.24S/Co3S4/NF-4 h (1:2) catalyst is almost unchanged after 500 cycles at a current density of 10 mA cm−2. The excellent HER activity and stability of the catalyst can be attributed to the heterostructure, which can further increase the number of active sites. This work provides a new direction for the preparation of highly efficient and stable heteromorphic non-noble metal catalysts for hydrogen evolution reaction.