Vertical MoSe2-MoOx p-n heterojunction and its application in optoelectronics

摘要

The hybrid n-type 2D transition-metal dichalcogenide (TMD)/p-type oxide van der Waals (vdW) heterojunction nanosheets consist of 2D layered MoSe2 (the n-type 2D material) and MoOx (the p-type oxide) which are grown on SiO2/Si substrates for the first time via chemical vapor deposition technique, displaying the regular hexagon structures with the average length dimension of sides of similar to 8 mu m. Vertical MoSe2-MoOx p-n heterojunctions demonstrate obviously current-rectifying characteristic, and it can be tuned via gate voltage. What is more, the photodetector based on vertical MoSe2-MoOx heterojunctions displays optimal photoresponse behavior, generating the responsivity, detectivity, and external quantum efficiency to 3.4 AW(-1), 0.85. x. 10(8) Jones, and 1665.6%, respectively, at V-ds = 5 V with the light wavelength of 254 nm under 0.29mWcm(-2). These results furnish a building block on investigating the flexible and transparent properties of vdW and further optimizing the structure of the devices for better optoelectronic and electronic performance.