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In this work, the electrical property of Au/graphene oxide/p-InP hetero-structure has been evaluated byI–VandC–Vmeasurements in dark and illuminated conditions (visible light). The diode exhibited significant rectifying behavior, thus indicating the heterojunction-type diode. The key electrical parameters of heterojunction diode including ideality factor (n), series resistance (Rs), shunt resistance (Rsh), and barrier height (Фb) are estimated fromI–Vdata based on the theory of thermionic emission. The modified Norde and Cheung’s methods were utilized to evaluate the electrical parameters and compared the results. The current conduction mechanism at different voltage regions ofI–Vhas also been investigated. The variation of 1/C2versus voltage signifies linearity at high frequency (1 MHz), indicating that the type of heterojunction can be abrupt. The experimental outcomes of this study revealed that the performance of heterojunction diode in dark is considerably good as compared to the illumination condition with respect to the lower values ofФb,n,Rs, and interface state density (Nss).

This paper investigates the properties of the urchin-like hollow spheres of vanadium pentoxide (UHS V2O5) network device. The device exhibited high photocurrent of μA with 102 rectification ratio under illumination due to the formation of a network device structure that reduced junction barrier and providing more electronic paths in our photodetector. The photovoltaic characteristics near zero bias were also observed when the device irradiated by 450 nm of 29.8 mW/cm2. The calculated open circuit voltage and short-circuit current were 0.26 V and 0.105 μA, respectively. The key performing parameters responsivity and specific detectivity of the fabricated device were (7.18-0.91) A/W and (5.94 × 1011-7.5 × 1010) Jones, respectively under the bias voltage of −5 V and an illumination power from (3.3–29.8) mW/cm2. The high-performance is attributed to the high-quality well-distributed UHS V2O5 network device that has more active sites and a large area of illumination that facilitate oxygen adsorption and desorption at the V2O5 surface.

Hybrid nanocomposite photodetectors are ideal systems with substantial applications as promising materials in the field of optoelectronics. In this study, the hydrothermal method was used to hybridise 2D rGO onto 1D V2O5 nanorods to form hybrid nanocomposites with excellent electrical and photoconduction properties. Five different percentages of rGO content were added to V2O5 nanorods to examine the photodetection properties. A comprehensive comparison suggested that the optimal content of rGO intercalated into V2O5 nanorods were determined by gaining maximum photoresponse . The high performance of optimised photodetectors is ascribed to various photoconductive paths, effective generation, and transport along with lower recombination of carriers in devices. For the optimised VG40 photodetectors responsivity and specific detectivity were calculated as 12.6 A/W and 5.78 × 1011 Jones respectively, for 532 nm illumination source at a bias voltage of -2 V. A closer examination found that the optimized VG40 shows photovoltaic behaviour at 0 V. The excellent device performance of the synergistic effect of rGO is due to improve current generation and transport mechanisms. These results demonstrated a suitable approach for the synthesis of a surfactant or binder-free hybrid nanocomposite for practical photodetection applications.

In this paper, a graphene photodetector modified with both gold nanoparticles and silver nanoparticles was discussed. The performance of the photodetector was improved by the common electrode structure prepared by transferring graphene on the top of the device. The gold nanoparticles and silver nanoparticles prepared via the annealing process can excite localized surface plasmon under illumination, and the photoresponse of the photodetector in the wavelength range of 400−470 nm and 510−620 nm. The responsivity increased by up to 2.8 times. As the photosensitive material, graphene on the top participated in photoelectric response, improving the performance of the photodetector in the wavelength range of 400−850 nm, and realized 1.4–1.5 times performance improvement in the wide-band range. Through the above improvements, the responsivity of the photodetector under 400−470 nm and 510−620 nm illumination increased by 2–4 times; the specific detectivity under 450 nm illumination increased by 2.7 times, and the external quantum efficiency increased by 400 %. Therefore, the photodetector can achieve enhancement in its multi-band selective response and improvement in its optical detection performance in a wide-band range.