Self-powered poly(3-hexylthiophene)/ZnO heterojunction ultraviolet photodetectors decorated by silver nanoparticles

Self-powered poly (3-hexylthiophene)/zinc oxide (P3HT/ZnO) heterojunction ultraviolet photodetectors decorated by silver nanoparticles (Ag NPs) were fabricated by sol-gel and spin-coating techniques. The ultraviolet photoresponse performance of the P3HT/ZnO heterojunction photodetectors influenced by the position of plasmonic Ag NPs was investigated. The responsivity and detectivity of the P3HT/Ag/ZnO photodetector with placed Ag NPs at the interface of ZnO and P3HT layers enhanced to 1.92 and 1.15 times compared to the reference devices. When the Ag NPs embedded into ZnO layer , the responsivity, detectivity and external quantum efficiency were 16.42 mA/W, 5.97 × 10 11 Jones, and 5.36 %, respectively, which were 5.77 times, 4.64 times and 5.77 times to that of the pristine P3HT/ZnO photodetector. The enhancement mechanism of plasmonic metallic nanoparticles to the performance of the photodetectors was discussed in details. This study presents a simple route to high performance self-powered photodetectors.