Ultrathin 1T-phase MoS2 nanosheets decorated hollow carbon microspheres as highly efficient catalysts for solar energy harvesting and storage

Abstract

The composite of MoS2 and hollow carbon sphere (MoS2@HCS) is prepared via a glucose-assisted one pot synthesis. The composite consists of hierarchical spheres with a diameter of 0.5–4 μm and these hollow spheres are decorated with a number of curled and interlaced MoS2 nanosheets. After the composite is subject to the lithium intercalation, the MoS2 is converted from 2H to 1T phase. In this current work, the activities of 1T-MoS2@HCS toward photocatalytic hydrogen evolution and the reduction of I3− in dye-sensitized solar cells (DSCs) are systemically investigated. When evaluated as the photocatalyst for hydrogen evolution, the amount of evolved hydrogen over 1T-MoS2@HCS can reach 143 μmol in 2 h, being 3.6 times higher than as-synthesized 2H-MoS2@HCS. Additionally, the 1T-MoS2@HCS can be employed as the counter electrode (CE) material in DSCs. The DSCs based on 1T-MoS2@HCS CE possesses the power conversion efficiency of 8.94%, being higher than that with 2H-MoS2@HCS CE (8.16%) and comparable to that with Pt CE (8.87%). Our study demonstrates that 1T-MoS2@HCS has a great potential as an inexpensive alternative to Pt catalysts.