Gap States Assisted MoO3 Nanobelt Photodetector with Wide Spectrum Response

作者：Xiang Du; Han Cheng; Zhang Jialin; Chen Wei^*

来源：Scientific Reports, 2014, 4(1): 4891.

DOI：10.1038/srep04891

Molybdenum oxides have been widely investigated for their broad applications ranging from electronics to energy storage. Photodetectors based on molybdenum trioxide (MoO3), however, were seldom reported owing to their low conductivity and weak photoresponse. Herein we report a photodetector based on single MoO3 nanobelt with wide visible spectrum response by introducing substantial gap states via H-2 annealing. The pristine MoO3 nanobelt possessed low electrical conductance and no photoresponse for nearly all visible lights. The H-2 annealing can significantly improve the conductance of MoO3 nanobelt, and result in a good photodetector with wide visible spectrum response. Under illumination of 680 nm light, the photodetector exhibited high responsivity of similar to 56 A/W and external quantum efficiency of similar to 10200%. As corroborated by in situ ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy investigations, such strong wide spectrum photoresponse arises from the largely enriched gap states in the MoO3 nanobelt after H-2 annealing.

• 出版日期2014-5-8