Spectral Conversion From Ultraviolet to Near Infrared in Yb3+-Doped Pyrovanadate Zn2V2O7 Particles

Yb3+-doped Zn2V2O7 particles were synthesized via the Pechini method. The crystal structure and morphology of the polycrystalline samples were investigated by X-ray powder diffraction and scanning electron microscopy measurements, respectively. The reflectance spectrum, photoluminescence excitation, emission spectra, and the absolute quantum efficiency of the IR emission (900-1100) were measured. The intense near-IR emission around 1000nm attributed to the F-2(5/2) F-2(7/2) transition of Yb3+ was observed under the excitation of ultraviolet light in the Yb3+-doped pyrovanadate. The efficient energy transfer from VO4 groups into Yb3+ ions was confirmed by the optical spectra and fluorescent lifetime measurements. These results demonstrate that the Yb3+-doped pyrovanadate particles are promising materials for spectral conversion from visible sunlight to near-infrared emission and it may have potential application for spectral convertor to enhance the photoelectric conversion efficiency of c-Si solar cells.