Photoluminescence Properties Of Rare Earth Doped Perovskite Layered Compounds And Nanosheets

Two dimensional nanomaterials attract much attention in recent years. Preparing two dimensional nanomaterials with photoluminescence properties has potential applications in electronic and biomedical area. Perovskite layered compounds were used as starting materials to prepare nanosheets. Rare earth elements were doped in starting materials to prepare nanosheets with photoluminescence properties. Er3+/Yb3+ions co-doped LaNb2O7and La2Ti3O10nanosheets, and Nd3+ions doped LaNb2O7nanosheets was prepared and photoluminescence properties of them were analysed. The conclusions and results were summarized as follows:Er3+/Yb3+co-doped KLaNb2O7samples were prepared by high temperature solid method as starting materials. Samples of HLaNb2O7were carried out by proton exchange, and two dimensional nanosheets colloidal solution was achieved by exfoliation progress. The size of nanosheets was analyzed by AFM that the thickness is1.6nm. The morphologies of starting materials, proton-exchanged forms and deposition of exfoliated HLaNb2O7were analyzed by SEM. Emission spectra were measured using an excitation with the wavelength of980nm, and excitation wavelength of525nm-553nm and653nm-666nm were obtained. The dependence of up-conversion luminescence intensity of materials on Er3+/Yb3+co-doping concentrations, proton exchange and exfoliation progress were analyzed.Er3+/Yb3+co-doped K2La2Ti3O10samples were prepared by high temperature solid method, HLa2Ti3O10were carried out by proton exchange, and nanosheets colloidal solution was achieved by exfoliation progress. Emission spectra were measured using an excitation with the wavelength of980nm, and excitation wavelength of525nm-553nm and653nm-666nm were obtained. The dependence of up-conversion luminescence intensity of materials on Er3+/Yb3+co-doping concentrations were analyzed. Besides, the reason for that the up-conversion luminescence intensity of samples after proton exchange was sharply decreased was analyzed. Nd3+doped KLaNb2O7samples were prepared by high temperature solid method, HLzNb2O7were carried out by proton exchange, and two dimensional nanosheets colloidal solution was achieved by exfoliation progress. The size of nanosheets was analyzed by AFM that the thickness is1.64nm. Emission spectra was measured using an excitation with the wavelength of808nm, and excitation wavelength of880nm,1060nm,1340nm were obtained. The dependence of photoluminescence intensity of nanosheets colloidal solution on Nd3+doping concentrations and organic medium were analyzed. Surface modification of nanosheets using silane coupling agent were analyzed, and the photoluminescence intensity of modified nanosheets was obviously increased. It was proved that the photoluminescence intensity of nanosheets was affected by environment around them. The reasons for decreasing of photoluminescence intensity and the methods for increasing photoluminescence intensity were analyzed.