Efficient conversion from UV light to near-IR emission in Yb3+-doped triple-layered perovskite CaLaNb3O10

Yb3+-doped triple-layered perovskite CaLaNb3O10 micro-particles were synthesized via the solid-state reaction method. The crystal structure and morphology of the polycrystalline samples were investigated by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) measurements, respectively. The reflectance spectra, photoluminescence (PL) excitation and emission spectra, the decay curves, and the absolute quantum efficiency (QE) of the near-infrared (NIR) emission (910–1100 nm) were measured. Under excitation of UV light, Yb3+-doped perovskite shows an intense NIR emission attributed to the 2F5/2 → 2F7/2 transitions of Yb3+ ions, which could match maximum spectral response of a Si-based solar cell. This is beneficial for its possible application in an enhancement of the photovoltaic conversion efficiency of solar energy utilization. The efficient energy transfer in Yb3+-doped CaLaNb3O10 from NbO6 groups into Yb3+ ions was confirmed by the spectra and fluorescent decay measurements. Cooperative energy transfer (CET) was supposed to be the NIR emission mechanism.

CaRNb3O10 is a self-activated oxide due to charge transfer transition in octahedral NbO6 groups. CaLaNb3O10:Yb3+ presents intense IR emission due to the cooperative energy transfer from host (NbO6) to Yb3+ is responsible. It could be expected to be potentially applicable for enhancing photovoltaic conversion efficiency of Si-based solar cells.Figure optionsDownload as PowerPoint slide