Largely enhanced near band edge emission of ultrathin zinc oxide nanowire/gold nanoparticles composites by surface plasmon resonance

Highlights: • Ultrathin ZnO nanowire was synthesized by PEI assisted low-temperature solution method. • NBE emission was enhanced 26 times when Au nanoparticles were deposited onto the ZnO nanowire surface. • ZnO nanowire defect emission was quenched to noise level after depositing Au nanoparticles. • The changing of NBE and defect emission were caused by SPR mediated energy transferring. Ultrathin zinc oxide nanowires with diameter less than 50 nm were synthesized by polyethyleneimine assisted solution method. Zinc oxide nanowire near band edge emission was enhanced obviously by gold nanoparticles coating, and a max 26 times enhancement was realized. The defects caused visible light emission was also quenched to noise level when gold was deposited more than 10 s. The large near band edge emission enhancement was caused by surface plasmon resonance mediated luminescent energy transfer, which absorbed the visible light energy and transferred to the near band edge emission. The large surface to volume ratio enhanced the coupling strength between gold nanoparticles and ultrathin zinc oxide nanowires. This research provide a method to improve the luminescent efficiency of zinc oxide nanowires.