1T-Phase MoS2 Nanosheets on TiO2 Nanorod Arrays: 3D Photoanode with Extraordinary Catalytic Performance

A novel three-dimensional (3D) photoanode with exfoliated MoS2 nanosheets on TiO2 nanorod arrays (TiO2 NAs) was successfully fabricated by combining hydrothermal and drop-casting methods. The influences of the different phases (1T and 2H) of the MoS2 nanosheets on the photoelectrochemical (PEC) performances of such a TiO2 NAs/MoS2 3D system have been systematically investigated. Parallel experiments revealed that the TiO2 NAs/1T-MoS2 composite with optimized 1T-MoS2 loading exhibited the highest photoelectric conversion efficiency, which was about 440 and 93% higher than those of the TiO2 NAs and the TiO2 NAs/2H-MoS2 counterpart, respectively. The enhanced catalytic performances of the TiO2 NAs/1T-MoS2 composite can be attributed to the superior conductivity of 1T-MoS2 and the strong interaction between TiO2 NAs and 1T-MoS2. The photogenerated holes can therefore transfer from the TiO2 NAs to the 1T-MoS2, thus leading to enhanced charge separation efficiency.