Self-powered, visible-light photodetector based on thermally reduced graphene oxide–ZnO (rGO–ZnO) hybrid nanostructure

Abstract

Here we report a new type of self-powered, visible-light photodetector fabricated from thermally reduced rGO-ZnO hybrid nanostructure. The photocurrent generation of the photodetectors under zero-bias enables hybrid rGO-ZnO devices to work like photovoltaic cells, which could power themselves without electrical power input. The thermal treatment at elevated temperature not only reduces graphene oxide (GO) into reduced graphene oxide (rGO), but also dopes the ZnO nanoparticles with carbon atoms, enabling their visible-light photoresponse capability. The pronounced and fast photocurrent generation was attributed to the efficient charge transfer between the rGO and carbon-doped ZnO nanoparticles, which were in intimate contact. The efficient charge transfer of the rGO-ZnO hybrid nanostructures also indicates that there could be applications in other light energy harvesting devices, including solar cells, sensors and visible-light photocatalysis.

Realization of a reduced graphene oxide/ZnO nanorod photodetector, suitable for self-powered applications

“…The other point which can be observed in this table is that there is not any measurable output sensitivity to red illumination in ZnO structure; however the rGO/ZnO structure shows a detectable sensitivity. This observation can be related to both the photogenerated carriers in rGO and the trap-assisted photogenerated carriers in ZnO, which are originated from the carbon-induced midgap subbands [8]. Also, it is notable that the reported output sensitivity (S) is enhanced by about two orders of magnitude, comparing to previously reported photodetector based on rGO/ZnO nanoparticle [8], at similar bias voltages.…”

“…This observation can be related to both the photogenerated carriers in rGO and the trap-assisted photogenerated carriers in ZnO, which are originated from the carbon-induced midgap subbands [8]. Also, it is notable that the reported output sensitivity (S) is enhanced by about two orders of magnitude, comparing to previously reported photodetector based on rGO/ZnO nanoparticle [8], at similar bias voltages. The observed synergic effect of rGO and ZnO nanorods in the realized hybrid UV photodetector can be attributed to the high optical absorption in ZnO nanorod array, effective charge transfer between the ZnO/rGO interface and fast charge transport by rGO.…”

“…Similarly, the weak Schottky contact at the interface of ZnO/rGO layer can help to separation of photogenerated carriers near the junction and lead to enhance the optoelectric sensitivity. the surface of nanorods [8]. Table 3 summarizes the achieved output characteristics of the realized self-powered photodetectors, which highlights the improved photoresponse of the rGO/ZnO based nanogenerator in comparison with the ZnO based structure.…”

“…This attractive properties make graphene an excellent carrier transporter material in optoelectronic devices, which benefits from both high carrier mobility and optical transparency [4][5][6]. Regarding this, some groups have applied semiconductor-graphene hybrid photodetectors and reported improved performances [7][8][9]. On the other hand, reduced graphene oxide (rGO) can be achieved by simple and low cost synthesis methods, and shows properties similar to graphene sheets.…”

Analytical Model of Double Gate MOSFET for High Sensitivity Low Power Photosensor

“…Thus it is capable for detection mainly in UV, visible region. Photodetection in the visible-light zone is of great importance for various applications including environmental and biological research, sensing, detection, missile launch and imaging applications [31]. Various applications of UV detectors are UV dosimetry and imaging, solar UV measurements and astronomical studies, flame sensors (fire alarm systems, missile plume detection, combustion engine control) and biological and chemical sensors (ozone detection, determination of pollution levels in air, biological agents detection etc.)…”