Two-Dimensional Alloyed Mo0.5W0.5S2 Nanosheets for Photoelectrochemical Photodetection

In the field of photodetection, transition metal dichalcogenides (TMDs) have currently been one of the main active materials, where molybdenum disulfide and tungsten disulfide have been widely explored. In this study, two-dimensional (2D) Mo0.5W0.5S2 was successfully prepared by a liquid phase exfoliation method. The 2D structure of Mo0.5W0.5S2 nanosheets (NSs) is evident from the characterization images based on transmission electron microscopy and scanning electron microscopy. The as-fabricated Mo0.5W0.5S2 NSs are directly used as active materials for constructing photoelectrochemical type photodetectors (PDs), exhibiting excellent photoresponse performances. The photoelectric detection perform-ance of Mo0.5W0.5S2 was investigated in alkaline electrolytes with various concentrations, and the effect of bias potentials is also revealed. In addition, the Mo0.5W0.5S2 NSs exhibit outstanding stability in 1000 cycles, where the average decrements of 0.2 and 0.08% per cycle are observed for the fresh sample and the one stored for 1 month, respectively. It is believed that this study will provide a valuable reference for the research of TMD-based PDs.