Photodetector-Based Material from a Highly Sensitive Free-Standing Graphene Oxide/Polypyrrole Nanocomposite

Abstract

This paper describes the establishment of free-standing rolled graphene oxide (roll-GO) and polypyrrole (Ppy) using a modified Hummer method and oxidative polymerization. Then, a photodetector was created by removing a thin film of the free-standing rolled graphene oxide from a filter paper and attaching it to a tape. The chemical structure of the roll-GO was confirmed using XRD and FTIR analysis, while SEM and TEM showed that it was rolled in nature. The material had a small bandgap of 2.4 eV and a high current density in light conditions. The photodetector responded well to monochromatic light, with Jph values changing from 0.027 to 0.019 mA/cm2 as the light wavelengths decreased from 340 to 730 nm. The photoresponsivity (R) and detectivity (D) values were high, at 340 nm (0.27 mA/W and 6.0 × 107 Jones, respectively) and at 730 nm (0.19 and 4.25 × 107 Jones, respectively). The addition of Ppy improved these parameters, with the Ppy/roll-GO/tape photoelectrode showing excellent R and D values of 0.33 mA/W and 7.34 × 107 Jones, respectively. Furthermore, the production of a photocurrent at V = 0 indicated that the Ppy/roll-GO layer could be used for solar cell applications. Overall, the results suggest that the prepared free-standing Ppy/roll-GO/tape photodetector has high potential for use in the optical region between 340 and 730 nm and may be suitable for industrial applications.

Reduced Graphene Oxide/Se Microtube p–p Heterojunction for Self-Powered UV–NIR Broadband Photodetectors

“…Broadband photodetectors (PDs) play a crucial role in various fields, including environmental monitoring, imaging, fire detection, astronomical observation, remote sensing, scientific research, as well as industrial applications. − Traditional photodetector detection systems have certain drawbacks, such as complex circuitry and high energy consumption. To better adapt to diverse working environments, self-powered PDs have emerged with the advantageous feature of low power consumption or even no external energy supply. − Electron–hole pair separation and operation can be accomplished with minimal external power by utilizing heterojunctions or Schottky junctions to create an internal electric field for self-powering. − Nevertheless, self-powered PD imposes stringent requirements on hybrid materials and entails a relatively intricate preparation process, leading to higher production costs and significantly limiting the widespread adoption and utilization of PDs in practical applications. Therefore, it is imperative to consider both simplified operation and cost-effective photosensitive materials for the heterostructure while maintaining the broadband responsivity (UV–vis–IR) and self-powered properties of PDs.…”

“…RGO is a 2D-layered material that can be mass-produced at a reasonable cost using solution methods and has an abundance of oxygen functional groups. RGO possesses the advantages of a tunable band gap, modulated optoelectronic properties, enhanced light transmittance, and electrical conductivity. − As an appropriate heterostructure material for broadband PDs, the band gap of RGO is regulated by the reduction degree of GO. − High-performance IR PD based on RGO under 2 V exhibits a responsivity of 4 mA W –1 at 1550 nm, which is presented by Chitara et al In order to improve the self-powered characteristic, various semiconductors have been complexed with RGO layer materials. The RGO/Si vertical heterojunction fabricated by Li et al is extremely sensitive to light in the 365–1200 nm range, particularly at 600 nm, where it displays a responsivity of 1.52 mA W –1 with a high switch ratio of 10 4 .…”

Variable Angle Spectroscopic Ellipsometry Characterization of DMOAP-Functionalized Graphene Oxide Films

“…Graphene oxide (GO) is a material known for its immense potential [1][2][3][4][5][6], largely attributable to its extensive surface area, cost-effective production, and capability for direct interaction with various biomolecules and nanoparticles [7]. GO is distinctively characterized by a combination of sp 2 and sp 3 hybridized carbon atoms [8].…”

“…Graphene oxide (GO) is a material known for its immense potential [1][2][3][4][5][6], largely attributable to its extensive surface area, cost-effective production, and capability for direct interaction with various biomolecules and nanoparticles [7]. GO is distinctively characterized by a combination of sp 2 and sp 3 hybridized carbon atoms [8]. Furthermore, its structure is enriched by various functional groups, including epoxy, carboxyl, and hydroxyl [9], making it an ideal substrate for functionalization processes.…”

“…The optical properties of GO are greatly influenced by several key factors [18]. The intrinsic structural properties of GO, characterized by its mix of sp 2 and sp 3 hybridized carbon atoms and the presence of various functional groups, directly dictate its optical behavior. The degree of oxidation, which defines the types and amounts of oxygencontaining groups, has a direct impact on these properties.…”