title: Structure and Photoluminescent Properties of ZnO Encapsulated in Mesoporous Silica SBA-15 Fabricated by Two-Solvent Strategy.
abstract: The two-solvent method was employed to prepare ZnO encapsulated in mesoporous silica (ZnO/SBA-15). The prepared ZnO/SBA-15 samples have been studied by X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, nitrogen adsorption-desorption isotherm, and photoluminescence spectroscopy. The ZnO/SBA-15 nanocomposite has the ordered hexagonal mesostructure of SBA-15. ZnO clusters of a high loading are distributed in the channels of SBA-15. Photoluminescence spectra show the UV emission band around 368 nm, the violet emission around 420 nm, and the blue emission around 457 nm. The UV emission is attributed to band-edge emission of ZnO. The violet emission results from the oxygen vacancies on the ZnO-SiO(2) interface traps. The blue emission is from the oxygen vacancies or interstitial zinc ions of ZnO. The UV emission and blue emission show a blue-shift phenomenon due to quantum-confinement-induced energy gap enhancement of ZnO clusters. The ZnO clusters encapsulated in SBA-15 can be used as light-emitting diodes and ultraviolet nanolasers.
authors.affiliation: Institute of Materials Science and Engineering, Lanzhou University, Lanzhou, 730000 China.
authors.forename: Qingshan
authors.initials: Q
authors.lastname: Lu
authors.forename: Zhongying
authors.initials: Z
authors.lastname: Wang
authors.forename: Jiangong
authors.initials: J
authors.lastname: Li
authors.forename: Peiyu
authors.initials: P
authors.lastname: Wang
authors.forename: Xialei
authors.initials: X
authors.lastname: Ye