Photoluminescence enhancement OF Er3+-DOPED ZnO/SiO2 nanocomposites fabricated through two-step synthesis

• Published in: Optical materials 2019-06, Vol.92, p.262-266
• Main Authors: Hien, Le Thi Thu, Van Du, Nguyen, Ha, Ngo Ngoc, Hoa, Nguyen Duc, Khiem, Tran Ngoc, Chien, Nguyen Duc
• Format: Article
• Language: English
• Subjects: Energy transfer; Rare earth dopant; Sol–gel; ZnO/SiO2 nanocomposite
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2019.04.043

In this study, we demonstrated two processes for the fabrication of thin films comprising ZnO nanocrystals dispersed in a SiO2 matrix doped with Er3+ ions (Er3+-doped SiO2/ZnO nanocomposites). The thin films can be applied as SiO2 glasses for optical waveguide materials working at the 1.54 μm band. In the first process, the conventional sol–gel method was utilized to generate homogeneous materials wherein ZnO nanoparticles formed after heat treatment. In the second process, SiO2 and ZnO sols were separately prepared before the fabrication of Er3+-doped nanocomposites. Different fabrication conditions, such as doping concentration and heat treatment temperature, and the optical properties of the corresponding prepared films were presented. The optical properties of the two material systems were compared to propose and discuss different excitation mechanisms via the interaction between intermediate ZnO nanocrystals and Er3+dopants. •Thin films comprise Er3+-doped ZnO/SiO2 nanocomposites.•Optimal conditions obtained for different fabrication processes.•The separation of ZnO nanocrystals and Er3+ dopants enhances Er-related PL.•Excitation mechanisms of Er3+ dopants are proposed and discussed.