Hybrid effects of CdSe/ZnS quantum dots on p–n heterojunction organic nanowire

Abstract

We demonstrate that the optical and photoresponsive electrical properties of a single nanowire (NW) consisting of a p-type poly(3-hexylthiophene) (P3HT) and n-type [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) were changed by hybridization with functionalized CdSe/ZnS QDs. Surface decorating and bulky infiltrating methods were employed for the hybridization of the QDs with the NWs. For the QD-infiltrated P3HT/PCBM single NW, the current density in both dark and light conditions was clearly enhanced and the nanoscale photoluminescence (PL) intensity was reduced due to the charge transfer effect. For the P3HT/PCBM NWs decorated with QDs, the current density was not changed much, however, the PL characteristics of both the QDs and the NWs were simultaneously changed by the energy transfer effect. From time-resolved PL spectra, the exciton lifetimes of the QDs in the hybrid NWs drastically decreased through the hybridization with the NWs, supporting the charge and/or energy transfer effects.