title: Enhancing UV-emissions through optical and electronic dual-function tuning of Ag nanoparticles hybridized with n-ZnO nanorods/p-GaN heterojunction light-emitting diodes.
abstract: ZnO nanorods (NRs) and Ag nanoparticles (NPs) are known to enhance the luminescence of light-emitting diodes (LEDs) through the high directionality of waveguide mode transmission and efficient energy transfer of localized surface plasmon (LSP) resonances, respectively. In this work, we have demonstrated Ag NP-incorporated n-ZnO NRs/p-GaN heterojunctions by facilely hydrothermally growing ZnO NRs on Ag NP-covered GaN, in which the Ag NPs were introduced and randomly distributed on the p-GaN surface to excite the LSP resonances. Compared with the reference LED, the light-output power of the near-band-edge (NBE) emission (ZnO, λ = 380 nm) of our hybridized structure is increased almost 1.5-2 times and can be further modified in a controlled manner by varying the surface morphology of the surrounding medium of the Ag NPs. The improved light-output power is mainly attributed to the LSP resonance between the NBE emission of ZnO NRs and LSPs in Ag NPs. We also observed different behaviors in the electroluminescence (EL) spectra as the injection current increases for the treatment and reference LEDs. This observation might be attributed to the modification of the energy band diagram for introducing Ag NPs at the interface between n-ZnO NRs and p-GaN. Our results pave the way for developing advanced nanostructured LED devices with high luminescence efficiency in the UV emission regime.
authors: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec. 4, Ting-Chou Road, Taipei 116, Taiwan. yajulee@ntnu.edu.tw.
authors: Yung-Chi
authors: YC
authors: Yao
authors: Institute of Photonic System, National Chiao Tung University, 301, Gaofa 3rd Road, Tainan 711, Taiwan. zupoyang@nctu.edu.tw.
authors: Zu-Po
authors: ZP
authors: Yang
authors: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec. 4, Ting-Chou Road, Taipei 116, Taiwan. yajulee@ntnu.edu.tw and Advanced Lighting Technology Department, Green Energy and Environment Research Laboratories, Industrial Technology Research Institute (ITRI), Hsinchu 310, Taiwan.
authors: Jung-Min
authors: JM
authors: Hwang
authors: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec. 4, Ting-Chou Road, Taipei 116, Taiwan. yajulee@ntnu.edu.tw.
authors: Yi-Lun
authors: YL
authors: Chuang
authors: Institute of Photonic System, National Chiao Tung University, 301, Gaofa 3rd Road, Tainan 711, Taiwan. zupoyang@nctu.edu.tw.
authors: Chia-Ching
authors: CC
authors: Lin
authors: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec. 4, Ting-Chou Road, Taipei 116, Taiwan. yajulee@ntnu.edu.tw.
authors: Jing-Yu
authors: JY
authors: Haung
authors: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec. 4, Ting-Chou Road, Taipei 116, Taiwan. yajulee@ntnu.edu.tw.
authors: Chun-Yang
authors: CY
authors: Chou
authors: Department of Photonics, National Cheng Kung University, 1, University Rd, Tainan, 701, Taiwan.
authors: Jinn-Kong
authors: JK
authors: Sheu
authors: Department of Electrical Engineering, Chang Gung University, 259, Wen-Hwa 1st Rd, Kwei-Shan Dist., Taoyuan, 33302, Taiwan.
authors: Meng-Tsan
authors: MT
authors: Tsai
authors: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, 88, Sec. 4, Ting-Chou Road, Taipei 116, Taiwan. yajulee@ntnu.edu.tw.
authors: Ya-Ju
authors: YJ
authors: Lee