Enhanced near-infrared quantum cutting luminescence in 1,2,4,5-benzenetetracarboxylic acid/NaYF4:Tb3+, Yb3+ hybrid nanoparticles

Abstract

The ultra-small-sized NaYF₄:Tb³⁺, Yb³⁺ nanoparticles and hybrid L-NaYF₄:Tb³⁺, Yb³⁺ (L: dehydro-1,2,4,5-benzenetetracarboxylic acid) nanoparticles have been prepared by a hydrothermal synthesis and water bath reflux method. X-Ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), Fourier transform infrared (FTIR) spectra, UV-vis absorption spectra, diffuse reflectance spectra, photoluminescence (PL) spectra, as well as kinetic decay are used to characterize the resulting samples. The hybrid nanoparticles display a broad absorption band from 230 nm to 530 nm by monitoring ²F_5/2 → ²F_7/2 transition of Yb³⁺ at 977 nm. Upon the excitation of π–π* transition of the organic 1,2,4,5-benzenetetracarboxylic acid (label with H₄L), the strong NIR emission at about 1000 nm that matches to energy of Si band gap of Si-based solar cells is obtained. As a downconversion luminescent converter, this kind of material might be useful in Si-based solar cells to reduce thermalization loss and enhance conversion efficiency of solar cells via spectral modification.