The Pt-free 1T/2H-MoS2/CdS/MnOx hollow core-shell nanocomposites toward overall water splitting via HER/OER synergy of 1T-MoS2/MnOx

Abstract

Hydrogen evolution reaction/Oxygen evolution reaction (HER/OER) synergy would be the most important issue for overall water splitting. The Pt-free 1T/2H-MoS2/CdS/MnOx hollow core–shell nanocomposites are fabricated via a continuous hydrothermal–chemical method; therefore, the OER co-catalysts MnOx and CdS shell are deposited on the surface of SiO2 nanosphere templates continuously via hydrothermal–chemical method. Subsequently, the SiO2 templates are etched via chemical method and the 2H-MoS2/CdS hollow core–shell heterojunction and 1T-MoS2 HER co-catalyst are introduced via one-step hydrothermal method. Evaluated by photocatalytic performance, the 1T/2H-MoS2/CdS/MnOx exhibits an enhanced HER performance of about ~50 folds than that of single CdS hollow nanosphere, and achieves a decent overall water splitting performance of about ~1668.00(H2)/824.61(O2) μmol/g∙h, which can be mainly ascribed to the well HER/OER synergy and formation of hollow core–shell structure. Therefore, the 1T-MoS2 with quick electron transport and decent solid/liquid interface can promote the photogenerated electron diffusing, the MnOx with mixed Mn3+/Mn4+ ions can activate the hole-related species for OH− oxidation and promote H2O2 decomposition, the 2H–MoS2/CdS heterojunction can separate the charge carrier and meet the potential to achieve overall water splitting. Additionally, the 1T/2H-MoS2 with decent lattice matching can improve the charge carrier transport, the 1T-MoS2 with sufficient specific surface areas can increase active sites and the hollow core–shell structure can increase solar efficiency which is also beneficial for enhancing the overall water splitting performance and stability.