Exploring the Electrical Performance of GO:Ag Nanoparticles Synthesized via Bacterial Method for Interfacial Applications in Ag/GO:Ag/p-Si Structures: I-V and C-V Analysis

Abstract In this study, Ag-doped graphene oxide (GO:Ag) nanoparticles were successfully synthesized via an eco-friendly bacterial reduction method, marking the first reported use of this biological approach in GO:Ag nanocomposite fabrication. The synthesized nanoparticles, characterized by TEM, revealed Ag particles ranging from 45 to 70 nm homogeneously distributed on GO sheets. These GO:Ag nanocomposites were deposited on both glass and p-type silicon (p-Si) substrates using a controlled drop-casting method at 300 °C to form uniform thin films. Optical measurements indicated a narrowed band gap of 0.75 eV, attributed to the electronic interaction between Ag and GO. XRD and Raman analyses confirmed the presence of crystalline cubic-phase Ag nanoparticles within the hexagonal GO lattice. SEM and EDX results showed uniform dispersion of 47–78 nm Ag nanospheres throughout the film. Cross-sectional SEM analysis further revealed the typical wrinkled, sheet-like morphology of the GO layers, confirming their retention and layered stacking during film formation. The resulting thin films were integrated as an interfacial layer in Ag/GO:Ag/p-Si/Ag diode structures. Electrical characterizations under ambient conditions demonstrated rectifying behavior, with calculated parameters including an ideality factor of 2.30, a barrier height of 0.76 eV, and a saturation current of 1.78 × 10 −17 A. Capacitance–voltage (C–V) measurements further provided insights into doping concentration, diffusion potential, and interface quality. These findings validate the potential of biologically synthesized GO:Ag thin films as a sustainable, low-cost, and effective material for future nanoelectronic device applications.