Upconversion red light emission and luminescence thermometry of Gd2O3:Er3+ @Gd2O3:Yb3+ core-shell nanofibers synthesized via electrospinning

Gd2O3:Er3+@Gd2O3:Yb3+ core-shell nanofibers with cubic phase were successfully fabricated by electrospinning method. The structural, morphological properties were investigated by X-Ray diffraction, scanning electron microscopy. Under 980 nm excitation, the upconversion photoluminescence in visible light exhibits strong red emitting band with obvious splitting peaks resulted from stark splitting of energy level. The visible emissions are sensitive to temperature in the range of 303-543 K. The red emission displays quenching with elevation of temperature. The activation energy for thermal quenching is equal to 0.1408 eV. The temperature dependent multi-peaks of red emission were systematically investigated. Based on valley and peak ratio of I680.31nm/ I683.03nm in upconversion emission spectra, temperature sensing with constant absolute sensitivity was achieved. These results suggest Gd2O3:Er3+@Gd2O3:Yb3+ nanofibers are promising candidates for luminescence thermometry, which may provide their application values in both scientific research and industry.