biostudies-literatureUnknown16(6)Sharma IA self-powered visible-light photodetector was fabricated using a coumarin-derived Schiff base, 4-FMCSB, as the active layer. The compound was synthesized via a two-step process and characterized using FT-IR, NMR, MALDI-TOF-MS, and UV-vis spectroscopy. The optical band gap of 4-FMCSB was determined to be 2.33 eV, with DFT calculations confirming a HOMO-LUMO gap of 2.79 eV. Thin films of 4-FMCSB were deposited on ITO substrates via spin coating, and aluminium contacts were thermally evaporated to form Al/4-FMCSB/ITO photodetectors. The device exhibited a strong rectification ratio, rapid photo response (rise time: 510 ms; fall time: 210 ms), and efficient operation under zero bias. Key performance metrics included a responsivity of 12.6 mA W-1, detectivity of 9.31 ×RSC advances5455-5465https://www.ebi.ac.uk/biostudies/studies/S-EPMC12834207biostudies-literatureDesign and fabrication of a zero-bias visible light photodetector based on a coumarin-derived Schiff base thin film.PMC12834207K A JShil SKekuda DAnil Kumar NVSharma IfalseDesign and fabrication of a zero-bias visible light photodetector based on a coumarin-derived Schiff base thin film.A self-powered visible-light photodetector was fabricated using a coumarin-derived Schiff base, 4-FMCSB, as the active layer. The compound was synthesized via a two-step process and characterized using FT-IR, NMR, MALDI-TOF-MS, and UV-vis spectroscopy. The optical band gap of 4-FMCSB was determined to be 2.33 eV, with DFT calculations confirming a HOMO-LUMO gap of 2.79 eV. Thin films of 4-FMCSB were deposited on ITO substrates via spin coating, and aluminium contacts were thermally evaporated to form Al/4-FMCSB/ITO photodetectors. The device exhibited a strong rectification ratio, rapid photo response (rise time: 510 ms; fall time: 210 ms), and efficient operation under zero bias. Key performance metrics included a responsivity of 12.6 mA W-1, detectivity of 9.31 ×2026-01-01T00:00:00Z2026 Jan2026-06-13T05:28:03.828Z2026-06-13T03:09:15.966ZS-EPMC128342074160219810.1039/d5ra09436d