The generation of broadband white emission of theα-Y2Si2O7 nanocrystals was observed upon excitation by focused beam ofCW lasers operating in near infrared,visible and blue regions.The influence of excitation energy ...The generation of broadband white emission of theα-Y2Si2O7 nanocrystals was observed upon excitation by focused beam ofCW lasers operating in near infrared,visible and blue regions.The influence of excitation energy on order of process is presented.The temperature of sample emitting laser induced white emission(LIWE)was determined by luminescence nanothermometry technique.It is found that the temperature is much lower than that predicted by blackbody model characterized with the same energy.It is shown that the LIWE is accompanied by efficient photocurrent.An origin of white emission is discussed in terms of multiphoton ionization process leading to the inter valence charge transfer emission.展开更多
Rare earth(Ⅲ)diphenyl-4-amine sulfonates(RE(DAS)3·xH2O,RE=Eu^3+,Tb^3+)phosphors were synthesized by precursor method from barium diphenyl-4-amine sulfonate and rare earth sulfates.FTIR,TG/DSC coupled to mass spe...Rare earth(Ⅲ)diphenyl-4-amine sulfonates(RE(DAS)3·xH2O,RE=Eu^3+,Tb^3+)phosphors were synthesized by precursor method from barium diphenyl-4-amine sulfonate and rare earth sulfates.FTIR,TG/DSC coupled to mass spectrometry(TG/DSC/MS),X-ray powder diffraction(XPD),scanning electron microscopy(SEM)and photo luminesce nce(PL)spectroscopy were utilized to structurally and morphologically characterize the samples.Thermal decomposition of Eu(DAS)3·7H2O and Tb(DAS)3·2H2O at 973 K under dynamic air atmosphere results in crystalline Eu2O2SO4 and Tb2O2SO4 materials,respectively.Accordingly,MS spectra reveal the liberation of thermal decomposition products of precursors,largely as CO2,NO2 and SO2 gases.The diphenyl-4-amine sulfonate(DAS)ligand demonstrats a good stabilizing property for Eu^3+and Tb^3+ions.The Eu(DAS)3·7H2O and Tb(DAS)3·2H2O compounds display efficient red and green emissions,under UV excitation,arising from the 5D0→7FJ(J=0-4)and 5D4→7FJ(J=0-6)transitions of the Eu^3+and Tb^3+ions,respectively.展开更多
基金Project supported by the Natonal Research Centre,Poland(UMO-2015/19/N/ST5/02680)
文摘The generation of broadband white emission of theα-Y2Si2O7 nanocrystals was observed upon excitation by focused beam ofCW lasers operating in near infrared,visible and blue regions.The influence of excitation energy on order of process is presented.The temperature of sample emitting laser induced white emission(LIWE)was determined by luminescence nanothermometry technique.It is found that the temperature is much lower than that predicted by blackbody model characterized with the same energy.It is shown that the LIWE is accompanied by efficient photocurrent.An origin of white emission is discussed in terms of multiphoton ionization process leading to the inter valence charge transfer emission.
基金Project supported by Higher Education Personnel Improvement Coordination(CAPES),Laboratory of Thermal Analysis Prof.Ivo Giolito(LATIG-USP),Laboratory of f-block Elements(Leb-f)USP,Petroleum Nucleus(LABPETRO-UFES)of Federal University of Espirito Santo,Institute of Low Temperature and Structure Research and the Polish Academy of Sciences
文摘Rare earth(Ⅲ)diphenyl-4-amine sulfonates(RE(DAS)3·xH2O,RE=Eu^3+,Tb^3+)phosphors were synthesized by precursor method from barium diphenyl-4-amine sulfonate and rare earth sulfates.FTIR,TG/DSC coupled to mass spectrometry(TG/DSC/MS),X-ray powder diffraction(XPD),scanning electron microscopy(SEM)and photo luminesce nce(PL)spectroscopy were utilized to structurally and morphologically characterize the samples.Thermal decomposition of Eu(DAS)3·7H2O and Tb(DAS)3·2H2O at 973 K under dynamic air atmosphere results in crystalline Eu2O2SO4 and Tb2O2SO4 materials,respectively.Accordingly,MS spectra reveal the liberation of thermal decomposition products of precursors,largely as CO2,NO2 and SO2 gases.The diphenyl-4-amine sulfonate(DAS)ligand demonstrats a good stabilizing property for Eu^3+and Tb^3+ions.The Eu(DAS)3·7H2O and Tb(DAS)3·2H2O compounds display efficient red and green emissions,under UV excitation,arising from the 5D0→7FJ(J=0-4)and 5D4→7FJ(J=0-6)transitions of the Eu^3+and Tb^3+ions,respectively.
