A Highly Sensitive Ag/MG-CQDs/ZnO NP Ultraviolet Photodetector

This article reports the fabrication of marigold flower-derived carbon quantum dots (MG-CQDs) and ZnO nanoparticle (NP)-layered thin-film-based ultraviolet (UV) photodetector (PD) on Si/SiO2 substrates. The MG-CQDs have been green synthesized from natural biomass marigold (MG) flowers by a facile, low-cost hydrothermal synthesis method. The ZnO NPs have been prepared through a rapid sol–gel process. The Ag/MG-CQDs/ZnO NP-layered thin-film-based fabricated UV PDs have good responsivity (
${R}$
), external quantum efficiency (EQE), and detectivity (
${D}^{\ast }$
) values 42.78 A/W, 14535.54%, and
${1.99}\times {10}^{{13}}$
jones, respectively, under UV radiation (365 nm). The response time of Ag/MG-CQDs/ZnO NP-fabricated UV PD shows adequate rise time (0.213 s) and fall time (0.085 s).