An efficient electrocatalytic catalyst for hydrogen production: MoS2/Cu2S/PANI with 'wheat ear' structure

In this study, MoS 2 /Cu 2 S/PANI with ‘wheat ear' structure was synthesized on nickel foam (NF) for electrocatalytic hydrogen production. The experimental results show that the catalyst exhibits excellent HER performance. At a current density of 10 mA cm −2 , it only has an overpotential of 98 mV. And it has good durability within 24 h. Compared with other materials, MoS 2 /Cu 2 S/PANI has better catalytic performance. There are three reasons for the enhancement of catalytic activity. On the one hand, polyaniline (PANI) has strong conductivity, which can improve the poor conductivity of MoS 2 . On the other hand, the nitrogen species derived from the PANI structural unit tend to bind metal ions such as Cu 2+ . Make the active material more evenly dispersed on the substrate. Cu 2+ further attracted negatively charged molybdate (MoO 4 2− ) to distribute uniformly on the surface of PANI. As a result, the synthesized molybdenum disulfide (MoS 2 ) is not stacked together, the specific surface area becomes larger, and the active sites increase. In addition, Cu 2 S, as a strong chemical bond between PANI and MoS 2 , should act as an electron transfer channel in the HER process. All of these make the composites exhibit excellent HER performance and thermal stability. Graphical abstract Synthesis mechanism of MoS 2 /Cu 2 S/PANI on nickel foam