Surface Plasmon Enhanced Nano Photodetectors Based On One Dimensional Nanostructures

Cadmium Selenium (CdSe) and Bismuth Sulfide (Bi2S3) are of particular interest because of its potential as important building blocks for a variety of electronic and optelectronic devices with moderate band-gap at room temperature. However, the device performance of the photodetector based on the two materials is still restricted by the relatively low responsivity. Extensively study has reveals that the poor device performance is mainly associated with the low cross-section of CdSe NRs, which are normally tens of nanometers in thickness.In this work, we present a plasmonic photodetector (PPD) with high sensitivity to red light illumination. The ultrasensitive PPD was composed of CdSe and Bi2S3 nanoribbons (NRs) decorated with plasmonic hollow gold nanoparticles (HGNs) on the surface, which were capable of coupling the incident light due to localized surface plasmon resonance (LSPR).It is found that the HGNs@CdSeNR and HGNs@Bi2S3NR photodetector exhibit apparent sensitivity to 650 nm light with good reproducibility. What is more, compared with the device without surface functionalization, the photocurrent is observed to increase considerably, leading to the responsivity and the detectivity have a obvious improvement. Theoretical simulation finds that the observed increase in photocurrent is due to LSPR induced direct electron transfer from the HGNs to CdSe and Bi2S3NR. The totality of this study suggests that the decoration with HGNs might be a rational strategy for managing light and optimising the device performance of semiconductor nanomaterials based optoelectronics.