Broadband UV Excited LaF₃:Eu 3+ Based Inorganic-Organic Mixed Hybrid Nanoparticles for Strong Luminescence.

Lanthanide ion doped nanoparticles can coordinate with some organic ligands to form the inorganic-organic hybrid nanoparticles, which exhibit greatly enhanced luminescence as a result of the energy transfer from the organic ligands to the lanthanide ions. However, when coordinating with a single type of organic ligand, their luminescence excitation spectral bandwidth is still quite limited. In this work, Eu3+-doped LaF3 (LaF3:Eu3+) nanoparticles, as the model inorganic material, were synthesized using the hydrothermal method. Instead of coordinating with a single type of organic ligand as previously studied, the LaF3:Eu3+ nanoparticles simultaneously coordinate with both benzoic acid and 2-thenoyltrifluoroacetone to form the inorganic-organic mixed hybrid nanoparticles. The mixed hybrid nanoparticles possess a broadband excitation spectrum (200~400 nm) which perfectly covers the entire ultraviolet (UV) spectral range of the solar radiation. By down-converting the UV light to visible light, their broadband UV excitation spectrum will be extremely beneficial to the enhancement of the conversion efficiency of silicon solar cells.