Core-shell ZnO:Ga-SiO nanocrystals: limiting particle agglomeration and increasing luminescence surface defect passivation

• Published in: RSC advances Vol. 9; no. 5; pp. 28946 - 28952
• Main Authors: Prochzková, Lenka, Van ek, Vojt ch, uba, Václav, Pjatkan, Radek, Martinez-Turtos, Rosana, Jakubec, Ivo, Buryi, Maksym, Omelkov, Sergey, Auffray, Etiennette, Lecoq, Paul, Mihóková, Eva, Nikl, Martin
• Format: Journal Article
• Published: 17.09.2019
• ISSN: 2046-2069
• DOI: 10.1039/c9ra04421c

Heat treatment is needed to increase the luminescence intensity of ZnO:Ga particles, but it comes at the cost of higher particle agglomeration. Higher agglomeration results in low transparency of scintillating powder when embedded in a matrix and constitutes one of the biggest disadvantages, besides low light yield and low stopping power, of ZnO:Ga powder. Limiting ZnO:Ga particle size is therefore a key step in order to prepare highly luminescent and transparent composites with prospects for optical applications. In this work, SiO 2 coating was successfully used to improve luminescence intensity or limitation of crystallite size growth during further annealing. Furthermore, ZnO:Ga and ZnO:Ga-SiO 2 core-shells were embedded in a polystyrene matrix. Heat treatment is needed to increase the luminescence intensity of ZnO:Ga particles, but it comes at the cost of higher particle agglomeration.