Near-infrared down-conversion and energy transfer mechanism in Yb(3+)-doped Ba2LaV3O11 phosphors

• Published in: Physical chemistry chemical physics : PCCP Vol. 17; no. 39; pp. 26330 - 26337
• Main Authors: Zhao, Jin, Guo, Chongfeng, Li, Ting, Song, Dan, Su, Xiangying
• Format: Journal Article
• Language: English
• Published: England 21.10.2015
• ISSN: 1463-9084
• DOI: 10.1039/c5cp04115e

Yb(3+)-doped Ba2LaV3O11 vanadate phosphors with near-infrared (NIR) emission are synthesized via the sol-gel method. The phase purity and structure of samples are characterized by X-ray diffraction (XRD). The electronic structure of the self-activated phosphor host Ba2LaV3O11 is estimated by density functional theory (DFT) calculation, and the host absorption is mainly ascribed to the charge transition from the O-2p to V-3d states. Photoluminescence emission (PL) and excitation (PLE) spectra, decay curves, absorption spectra and theoretical quantum yields of samples are also investigated. Results indicate that Ba2LaV3O11:Yb(3+) phosphors have strong broad band absorption and efficient NIR emission, which matches well with the spectral response of the Si-based solar cells. The energy transfer processes from [VO4](3-) to Yb(3+) and possible transfer models are proposed based on the concentration of Yb(3+) ions. Results demonstrate that Ba2LaV3O11:Yb(3+) phosphors might act as a promising NIR DC solar spectral converter to enhance the efficiency of the silicon solar cells by utilizing broad band absorption of the solar spectrum.