Preparation of a novel nanocomposite NaLuF4:Gd,Yb,Tm@SiO2@Ag@TiO2 with high photocatalytic activity driven by simulated solar light.

A novel nanocomposite photocatalyst NaLuF4:Gd,Yb,Tm@SiO2@Ag@TiO2 was developed for the first time. This composite material has a sandwich structure, including a NaLuF4:Gd,Yb,Tm upconversion nanocrystals (UCNCs) core, a media shell of amorphous SiO2 decorated with Ag nanoparticles, and an outer shell of anatase TiO2. The designed new structure takes advantage of the synergetic effect of UCNCs, Ag nanoparticles and TiO2.

Fabrication of a novel nanocomposite Ag/graphene@SiO2-NaLuF4:Yb,Gd,Er for large enhancement upconversion luminescence.

Upconversion nanocrystals have a lot of advantages over other fluorescent materials. However, their applications are still limited due to their comparatively low upconversion luminescence (UCL). In the present study, a novel nanocomposite of Ag/graphene@SiO2-NaLuF4:Yb,Gd,Er for enhancing UCL was fabricated successfully, and its morphology, crystalline phase, composition, and fluorescent property were investigated.

Synthesis of a novel core-shell nanocomposite Ag@SiO2@Lu2O3:Gd/Yb/Er for large enhancing upconversion luminescence and bioimaging.

Upconversion nanocrystals have many advantages over other fluorescent materials. However, their upconversion luminescence intensities are not desirable, limiting their applications for highly sensitive detection. Therefore, it is really important to enhance upconversion luminescent intensities of upconversion nanocrystals.

Synthesis of NaLuF4-based nanocrystals and large enhancement of upconversion luminescence of NaLuF4:Gd, Yb, Er by coating an active shell for bioimaging.

A series of NaLuF4-based hexagonal phase upconversion nanocrystals (UCNs) were synthesized by a facile solvothermal method and the properties of the UCNs were investigated. The results show that the as-prepared nanocrystals exhibit pure hexagonal lattice structures, uniform morphologies, high monodispersities and excellent upconversion luminescence. The upconversion luminescence (UCL) intensities of the UCNs can be enhanced by coating with a shell of NaLuF4.

Enhancing upconversion luminescence of NaYF4:Yb/Er nanocrystals by Mo(3+) doping and their application in bioimaging.

Enhancement of upconversion luminescence is imperative for the applications of upconversion nanocrystals (UCNs). In this work, we investigated the upconversion luminescence enhancement of NaYF4:Yb/Er by Mo(3+) ion doping. It was found that the upconversion luminescence intensities of the green and red emissions of UCNs co-doped with 10 mol% Mo(3+) ions were enhanced by 6 and 8 times, respectively.