Preparation of Cu@AgI Core–Shell Nanocolloid via Pulsed Laser Ablation for Enhanced Al/Cu@AgI/Si/Al Photodetector Performance

Abstract

This study seeks to synthesize Cu@AgI core-shell structures by laser ablation to fabricate high-performance Al/Cu@AgI/Si/Al photodetectors. The XRD results revealed that the AgI sample displayed diffraction peaks corresponding to silver iodide and silver oxide. The mean crystallite sizes were 28.08 nm for AgI and 31.28 nm for the core-shell structure. The particles had a quasi-spherical morphology, with a minimum diameter of 37.99 nm. The energy bandgap was 2.85 eV for AgI and 2.68 eV for Cu@AgI. The FTIR spectra indicated no notable alterations in the Cu@AgI core-shell structure, indicating the absence of lattice vibrations for AgI in the mid-IR. The Al/Cu@AgI/Si/Al photodetectors demonstrated peak specific detection at 450 nm and 900 nm, with quantum efficiency rising from 48.83% to 80.74%.