Significantly Enhanced Photoluminescence of Doped Polymer-Metal Hybrid Nanotubes


  • This work was supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (MEST) (No. R0A-2007-000-20053-0). The authors wish to thank to Professors Q. Park, D. S. Kim, and M. S. Choi for their assistance. Supporting Information is available online from Wiley InterScience or from the author.


We report on the significantly enhanced photoluminescence (PL) of hybrid double-layered nanotubes (HDLNTs) consisting of poly(3-methylthiophene) (P3MT) nanotubes with various doping levels enveloped by an inorganic, nickel (Ni) metal nanotube. From laser confocal microscopy PL experiments on a single strand of the doped-P3MT nanotubes and of their HDLNTs, the PL peak intensity of the HDLNT systems increased remarkably up to ∼350 times as the doping level of the P3MT nanotubes of the HDLNTs increased, which was confirmed by measurements of the quantum yield. In a comparison of the normalized ultraviolet and visible absorption spectra of the doped-P3MT nanotubes and their HDLNTs, new absorption peaks corresponding to surface-plasmon (SP) energy were created at 563 and 615 nm after the nanoscale Ni metal coating onto the P3MT nanotubes, and their intensity increased on increasing the doping level of the P3MT nanotube. The doping-induced bipolaron peaks of the HDLNTs of doped-P3MT/Ni were relatively reduced, compared with those of the doped-P3MT nanotubes before the Ni coating, due to the charge-transfer effect in the SP-resonance (SPR) coupling. Both energy-transfer and charge-transfer effects due to SP resonance contributed to the very-large enhancement of the PL efficiency of the doped-P3MT-based HDLNTs.