title: Luminescence enhancement of ZnO-core/a-SiN(x):H-shell nanorod arrays.
abstract: We report a remarkable improvement of photoluminescence from ZnO-core/a-SiN(x):H-shell nanorod arrays by modulating the bandgap of a-SiN(x):H shell. The a-SiN(x):H shell with a large bandgap can significantly enhance UV emission by more than 8 times compared with the uncoated ZnO nanorods. Moreover, it is found that the deep-level defect emission can be almost completely suppressed for all the core-shell nanostructures, which is independent of the bandgaps of a-SiN(x):H shells. Combining with the analysis of infrared absorption spectrum and luminescence characteristics of NH(x)-plasma treated ZnO nanorods, the improved photoluminescence is attributed to the decrease of nonradiative recombination probability and the reduction of surface band bending of ZnO cores due to the H and N passivation and the screening effect from the a-SiN(x):H shells. Our findings open up new possibilities for fabricating stable and efficient UV-only emitting devices.
authors.affiliation: Department of Physics and Electronic Engineering, Hanshan Normal University, Chaozhou, Guangdong 521041, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Huang
authors.forename: Shuigang
authors.initials: S
authors.lastname: Xu
authors.forename: Yanqing
authors.initials: Y
authors.lastname: Guo
authors.forename: Wenhao
authors.initials: W
authors.lastname: Guo
authors.forename: Xiang
authors.initials: X
authors.lastname: Wang
authors.forename: Chao
authors.initials: C
authors.lastname: Song
authors.forename: Jie
authors.initials: J
authors.lastname: Song
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.forename: Kin Ming
authors.initials: KM
authors.lastname: Ho
authors.forename: Ning
authors.initials: N
authors.lastname: Wang