Preparation of nanostructured PbI2/Si photodetector by magnetic field-assisted laser ablation in liquid

In this study, we report the synthesis of lead iodide PbI 2 nanoparticles (NPs) by magnetic field-assisted pulsed laser ablation in ethanol. Results of X-ray diffraction (XRD) show that the PbI 2 nanoparticles convert from amorphous to polycrystalline with a hexagonal structure as the magnetic field is applied. Star-like morphology is obtained when the magnetic field is used. UV–Vis results revealed that applying the magnetic field causes an increase in the optical band gap of PbI 2 NPs from 3.9 to 4.2 eV. The influence of the magnetic field on the figures of merit of the p-PbI 2 /n-Si heterojunction photodetectors was studied. current–voltage properties of the p-PbI 2 /n-Si heterojunction improved significantly when a magnetic field was applied. The fabricated photodetector works in the spectral region extending from visible to near infrared. Two peaks of response were observed in the responsivity data, whereas three peaks of response were observed in the responsivity of the photodetector fabricated with a magnetic field. The responsivity of the p-PbI 2 /n-Si photodetector increased from 0.23 to 0.64 A/W after the magnetic field was applied.