Photoconduction Properties in Tungsten Disulfide Nanostructures.

We reported the photoconduction properties of tungsten disulfide (WS 2 ) nanoflakes obtained by the mechanical exfoliation method. The photocurrent measurements were carried out using a 532 nm laser source with different illumination powers. The results reveal a linear dependence of photocurrent on the excitation power, and the photoresponsivity shows an independent behavior at higher light intensities (400-4000 Wm -2 ). The WS 2 photodetector exhibits superior performance with responsivity in the range of 36-73 AW -1 and a normalized gain in the range of 3.5-7.3 10 -6 cm 2 V -1 at a lower bias voltage of 1 V. The admirable photoresponse at different light intensities suggests that WS 2 nanostructures are of potential as a building block for novel optoelectronic device applications.