Sustainable fabrication of <scp>ZnO</scp> nanorod/ <scp>PVDF</scp> nanocomposites for ultraviolet photodetection and energy harvesting

Abstract This study explores the sustainable fabrication and characterization of poly(vinylidene fluoride) (PVDF) nanocomposite films doped with zinc oxide nanorods (ZnO‐NRs), synthesized via a green method using Cymbopogon citratus (lemongrass) as a natural reducing agent. Zinc acetate served as the precursor, enabling the first successful green synthesis of ZnO‐NRs. HRTEM confirmed the formation of uniform ZnO‐NRs with diameters of ~50 nm and lengths between 1 and 2 μm. The nanorods were incorporated into the PVDF matrix through sol–gel processing, and thin films were deposited onto ultrasonically cleaned glass substrates using spin coating. Structural, optical, and morphological properties were analyzed comprehensively. XRD revealed enhanced crystallinity with increasing ZnO content. UV–Vis spectroscopy confirmed a ZnO‐NR absorption peak at 375 nm, indicating a direct bandgap of 3.31 eV and improved UV‐light absorption. FTIR analysis demonstrated an α‐ to β‐phase transformation in PVDF, enhancing its piezoelectric properties. SEM and EDX confirmed uniform ZnO‐NR distribution within the PVDF matrix. Electrical properties were evaluated via current–voltage (I‐V) measurements of Au/PVDF/ZnO‐NR Schottky diodes, showing a significant photocurrent increase with photon energy. These results highlight the material's potential for UV photodetectors and piezoelectric energy harvesting. The green synthesis approach emphasizes environmental sustainability, making it promising for next‐generation optoelectronic applications. Highlights Eco‐friendly synthesis of ZnO‐NRs using Cymbopogon citratus . PVDF/ZnO‐NR films exhibit improved crystallinity and UV absorption. FTIR confirms α‐ to β‐phase transformation, enhancing piezoelectricity. SEM/EDX verifies uniform ZnO‐NR distribution in PVDF. Nanocomposite films show enhanced photocurrent for UV detection.