Realization of a Piezophototronic Device Based on Reduced Graphene Oxide/MoS2 Heterostructure

In this letter, we present a piezophototronic device based on reduced graphene oxide (rGO)/MoS
₂
heterostructure on a flexible substrate. Here, we benefit from the semiconducting and piezoelectric behaviors of MoS
₂
sheets, besides the 2-D properties of rGO sheets. To elaborate the piezophototronic behavior, first, we have studied the stress-induced and optoelectronic behaviors separately. It is shown that the rGO sheets play a dominant role in stress-induced variations of the electrical behavior of rGO/MoS
₂
bplay a dominant role in stress-induced variations of the electrical behavior of rGO/MoSased device. On the other hand, utilizing MoS
₂
sheets results in increasing the photoresponsivity of rGO/MoS
₂
-based photodetector by a factor of about 2.1, comparing with rGO-based device (at λ = 450 nm). Finally, the investigated piezophototronic behavior of the realized rGO/MoS
₂
-based device proves a responsivity enhancement of ~97%, by applying illumination and alternative strain (0.03%) simultaneously. The observed responsivity enhancement is attributed to the stress-induced piezopotential in MoS
₂
sheets, and the modulation of the Schottky barrier at rGO/MoS
₂
interface. The achieved results open up promising horizons for the coupling superior properties of MoS
₂
sheets, to realize new generation of high performance optoelectronic devices.