Efficient near-infrared quantum cutting in Yb3+ doped CaNb2O6 phosphor based on energy transfer

An efficient near-infrared (NIR) quantum cutting (QC) phosphor, CaNb2O6:Yb3+, has been developed to realize broadband downconversion from ultraviolet (UV) into NIR. Upon the excitation of UV light in the broad absorption band of niobate groups, an intense NIR emission of Yb3+ ion around 1 μm, matching the maximum spectral response of Si-based solar cells very well, was obtained. Through the analyses of the measured luminescence spectra and decay lifetimes, a mechanism of energy transfer from niobate groups to Yb3+ ions was proposed to rationalize the downconversion process. This broadband NIR QC phosphor might have potential application in enhancing response of Si-based solar cells via spectral modification.

► An efficient quantum cutting CaNb2O6:Yb3+ phosphor is prepared and characterized.
► Broadband downconversion from ultraviolet into near-infrared is realized.
► Cooperative energy transfer from niobate groups to Yb3+ ions is demonstrated.