Although the research on layered MoS2 photodetectors
has made great progress, their poor light absorption ability and complex
preparation process hinder their further commercial application. In
the present work, we report the growth of MoS2 square nanotubes
with high purity via a facile hydrothermal method for the first time.
Microstructure characterization demonstrates that the cavity structure
of the nanotubes can bring about a light trapping effect, thus obtaining
a strong photoelectric performance. The as-constructed MoS2 square nanotube photodetector with a paper substrate displays a
broadband response with a detection range of 375 to 915 nm. It exhibits
excellent performance with a high responsivity of 2.33 mA/W under
915 nm light irradiation, which is comparable to the best ones ever
reported for polycrystalline MoS2 photodetectors.