The co-modification of MoS2 and CdS on TiO2 nanotube array for improved photoelectrochemical properties

Herein, a heterostructure of MoS2/CdS/TiO2 nanotube arrays is constructed by successive ionic layer adsorption/reaction of CdS and dipping-assembly of MoS2 on the vertically oriented TiO2 nanotubes prepared by anodization method. The heterostructure is extensively investigated in terms of the composition, morphology, structural, and optical properties. It is observed that the co-modification of TiO2 nanotube arrays with CdS and MoS2 significantly enhances the visible light response and boosts the facile photo-generated electrons' transfer and charge separation efficiencies. Therefore, the prepared heterostructure photo-anode exhibits significantly enhanced photoelectrochemical properties including photocurrent, open circuit potential, and photo-conversion efficiencies compared with that of pure TiO2 nanotube arrays and CdS/TiO2 nanotube systems. Interestingly, it is found that the MoS2 coatings on the surface of CdS/TiO2 nanotube arrays greatly enhance their photoelectrochemical stability. The presented work demonstrates that MoS2/CdS/TiO2 nanotube heterostructures are a promising material for improved photoelectrochemical properties.