Controllable synthesis and upconversion emission of ultrasmall near-monodisperse lanthanide-doped Sr2LaF7 nanocrystals

• Published in: Journal of alloys and compounds Vol. 609; pp. 262 - 267
• Main Authors: Mao, Yifu, Ma, Mo, Gong, Lunjun, Xu, Changfu, Ren, Guozhong, Yang, Qibin
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 05.10.2014; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Nanocrystals and nanoparticles; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Sr2LaF7 nanocrystal; Ultrasmall; Upconversion; Sr2LaF7 nanocrystal; Upconversion; Ultrasmall; Doping; Photoluminescence; Solvothermal synthesis; Fluorescence; Frequency conversion; Lanthanum Strontium Fluorides Mixed; LaF; Rare earth additions; Chromaticity; Energy transfer; Nanocrystal; Crystal structure; Sr
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.04.168

[Display omitted] •Apropos NaOH content facilitates the growth of pure phase Sr2LaF7 NCs.•Yb3+ doping is favorable to the formation of Sr2LaF7 NCs with uniform size.•Ultrasmall near-monodispersed Sr2LaF7 NCs(sub-10nm) were synthesized for the first time.•Intense multicolor upconversion can be obtained by properly lanthanide doping. Fluorite phase Sr2LaF7 nanocrystals (NCs) were synthesized via solvothermal method using oleic acid as capping ligands. The effects of preparing conditions on the phase structure, crystal size, morphology, and upconversion (UC) emission properties of the products were studied. The results reveal that just apropos NaOH content facilitates the growth of near-monodispersed pure phase Sr2LaF7 NCs, and Yb3+ doping is favorable to the formation of pure Sr2LaF7 phase with more uniform size distribution. The average crystalline size of the products can be controlled less than 10nm. Following appropriate lanthanide ions doping, the NCs show intense blue, yellow, and white-color UC emission under the excitation of a 980nm laser. The energy transfer UC mechanisms for the fluorescent intensity were also investigated.