Synergistic Optical and Electrical Modulation in PVP@rGO Nanocomposites for Advanced Photodetector Applications

Reduced graphene oxide (rGO) and polyvinylpyrrolidone (PVP) are promising materials for the development of advanced nanocomposites due to the excellent electrical conductivity of rGO and the ability of PVP to stabilize dispersions of nanomaterials. In this study, we present the synthesis, characterization, and optoelectronic performance of PVP@rGO nanocomposites. Graphene oxide (GO) was synthesized via a modified Hummers’ method and reduced to rGO, which was then incorporated into PVP to form stable composites. The PVP@rGO composites were characterized using X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and UV–visible spectroscopy. The XRD pattern shows a broad (002) reflection of rGO near 25°, indicative of turbostratic graphitic ordering. The calculated average crystallite size, using the Debye–Scherrer equation, is approximately 4.5 nm, suggesting partially restacked nanosheets within the composite matrix. FTIR spectra indicated the reduction of GO to rGO, with the disappearance of oxygen‐containing groups and the appearance of characteristic CC bonds. SEM imaging revealed uniform dispersion of rGO within the PVP matrix, and UV–visible analysis showed a shift in the optical bandgap with increasing rGO content. The fabricated lateral‐type photodetector exhibited a strong and stable photocurrent response under 375 nm laser illumination, achieving a photoresponsivity of 98.39 A W −1 , a specific detectivity of 1.12 × 10 12 Jones, and a photosensitivity of 1.37 × 10 3 . These results demonstrate the excellent light‐to‐current conversion efficiency and highlight the promise of PVP@rGO nanocomposites for next‐generation optoelectronic and photodetection applications.