Layered MoS2 coupled MOFs-derived dual-phase TiO2 for enhanced photoelectrochemical performance

Abstract

In this work, we demonstrate a facile two-step hydrothermal method to synthesize layered MoS₂ coupled metal organic framework (MOF) derived dual-phase TiO₂ (MDT), as a photoanode for photoelectrochemical (PEC) water splitting and dye sensitized solar cells (DSSCs). The MOF-derived TiO₂ with a controllable pore size effectively prolongs the light traveling length and facilitates the interfacial carrier transport. Coupled with MoS₂, the visible light response property and the surface water oxidation kinetics of TiO₂ are obviously enhanced. Importantly, the multi-junction between layered MoS₂ and dual-phase TiO₂ suppresses the recombination rate of photoinduced electron–hole pairs and effectively enhances charge transfer kinetics. Used as a photoanode for DSSCs, the MDT demonstrates a maximum photocurrent density (J) of 17.72 mA cm⁻² with a power conversion efficiency (η) of 8.96%, more than 2 times higher than that of pure TiO₂ (η = 4.41%). Applied as a photoanode for PEC water splitting, it shows a photocurrent density of 1.2 mA cm⁻² at 1.23 V vs. RHE, compared with that of pure TiO₂ (J = 0.6 mA cm⁻²). The greatly improved PEC performance provides methods for building solar energy conversion devices by constructing MOF-derived functional materials.