Preparation, characterization and luminescence properties of perovskite La2Ti2O7:Eu3+ nanobelts by electrospinning

Quasi-one-dimensional [La(NO3)Eu3+(NO3)Ti3+(SO4)(2)]/PVP composite nanobelts were fabricated via electrospinning, and La2Ti2O7:Eu3+ nanobelts have been obtained after the relevant composite nanobelts were calcined at 800 degrees C in air for 8h. The structural properties were characterized by x-ray diffraction(XRD), field emission scanning electron microscope(FESEM), and transmission electron microscope(TEM). XRD analysis indicates that La2Ti2O7:Eu3+ nanobelts are monoclinic in structure with space group P2(1). FESEM and TEM analysis indicate the surface of [La(NO3)Eu3+(NO3)Ti3+(SO4)(2)]/PVP composite nanobelts is smooth, the width is ca. 3-4 mu m, and the thickness is ca. 160 nm. La2Ti2O7:Eu3+ nanobelts are composed of nanorods with the length ranging from 270 to 660 nm. The width of La2Ti2O7:Eu3+ nanobelts is ca. 3 mu m, and the thickness is ca. 140 nm. The photoluminescent(PL) properties of the La2Ti2O7:Eu3+ nanobelts were also studied. It is observed that the charge-transfer excitation bands of Eu3+ in the nanobelts are red-shifted with the increase of doping Eu3+ ion concentration. Under ultraviolet excitation of 274 nm, the La2Ti2O7:Eu3+ nanobelts emit the main emission peak at 615 nm, corresponding to D-5(0)-> F-7(2) transition of Eu3+. The PL emission intensity of Eu3+ increases with its doping concentration from 1 mol% to 9 mol% without concentration quenching effect. Possible formation mechanism of La2Ti2O7:Eu3+ nanobelts was proposed.