Graphene Quantum Dot‐Triggered Polyaniline‐ZnO Nano‐Leaves: Multifunctional Platform for Photocatalysis, Green Hydrogen Generation, Electrochemical Sensing, and Antimicrobial Resistance

Abstract Zinc Oxide, renowned for its outstanding optoelectronic properties as a model n‐type metal oxide, has been hailed as a promising material for the future. However, its practical application as an efficient photocatalyst is hindered by its low quantum efficiency and rapid electron–hole recombination. To circumvent this challenge and create ZnO‐based materials that respond to varied spectral range, the current project achieved successful preparation of graphene quantum dot decorated polyaniline‐wrapped zinc oxide nano‐leaves via facile route. The prepared photocatalyst was characterized by AT‐FTIR, UV–vis, and Raman spectroscopy, Four‐Probe conductivity meter and photoluminescence. Maximum hydrogen production achieved with 20 mg of fabricated photocatalyst was 6131 µmol/g with Apparent Quantum Efficiency (AQE) greater than 10%. The electrochemical evaluation of the fabricated system revealed a specific capacitance of 130 F/g at a scan rate of 10 mV/s. Electrical conductivity measurements using a Four‐Probe conductivity meter indicated a conductivity of 3.764 S/cm and a resistivity of 0.1358 Ω cm. These results highlight the potential of the prepared ternary nanocomposite for energy storage applications. Moreover, the synthesized PZGQD nanohybrid demonstrated promising environmental remediation capabilities, achieving 59% removal of tetracycline hydrochloride (TCH) at a rate constant of 0.01196 min −1 . Notably, the nanohybrid also exhibited significant antimicrobial activity, outperforming standard antibiotics against certain microbial strains.