Luminescent Gd2O3:Eu, NaGdF4:Eu, and NaGdF4:Ce/Eu Nanoparticles: Synthesis, Photophysical Properties, and Application for Enhanced Solar Cell Efficiency

Results of the synthesis and comprehensive characterization of rare earth oxide and fluoride nanoparticles Gd2O3:Eu3+, NaGdF4:Eu3+, and NaGdF4:Ce3+/Eu3+ are presented here. All nanoparticles were synthesized by thermal decomposition of organometallic precursors in high-boiling organic solvents. Structure, morphology and phase composition were studied using a wide range of physicochemical methods. It turned out that the introduction of Ce3+ with its allowed 4f–5d transitions promotes broadening of the excitation spectrum and significant enhancement of Eu3+ emission upon irradiation in the 254 nm region. Particular attention was paid to the study of energy transfer mechanisms, including the effect of Eu3+ ion concentration on the efficiency of cascade energy transfer along the Ce3+ → Gd3+ → Eu3+ channel. In order to assess the application potential, synthesized nanoparticles were encapsulated in a polyvinyl alcohol matrix and deposited on the surface of silicon solar cells. Resulting coating made it possible to increase the efficiency of photocurrent generation due to the spectral conversion of radiation from ultraviolet to visible spectral range.