# Fileset

[Tadashi C. Ozawa](https://mdr.nims.go.jp/filesets/4c34b17c-7179-4408-b86b-515a87af51fc/download)

## Creator

OZAWA, Tadashi

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[Preparation and Photoluminescence Characterizations of Eu3+-doped Oxide Nanosheets](https://mdr.nims.go.jp/datasets/9a5e2a2f-916a-46ef-a3bd-70bd33eba1e1)

## Fulltext

Microsoft PowerPoint - 2008光化学討論会-小澤忠20080905.ppt [互換モード]i ii iPreparation and PhotoluminePreparation and PhotoluminePreparation and PhotoluminePreparation and PhotoluminePreparation and PhotoluminePreparation and PhotolumineEE 3+3+ d d O id d O iEuEu3+3+ doped Oxidoped OxiEuEu33 --doped Oxidoped OxiEuEu doped Oxidoped OxiT d hi C  OZAWA*   K t t hi FUKUDA  K hTadashi C. OZAWA*,  Katsutoshi FUKUDA, KoshTadashi C. OZAWA ,  Katsutoshi FUKUDA, KoshS ft Ch i t  G  NSoft Chemistry Group, Nay pNational Institute for Materials Science  1-1National Institute for Materials Science, 1-1C t t il  OZAWContact email: OZAWI t dIntroduIntroduMost of the previously reported Ln-activated nanMost of the previously reported Ln-activated nancontaining complexes inserted betweencontaining complexes inserted betweenphotoluminescence properties of these internanophotoluminescence properties of these internanop p psusceptible to the amount of cointercalated spesusceptible to the amount of cointercalated spep pas energ transfer mediators In addition more eas energy-transfer mediators. In addition, more egy ,it t th h t ti t i t d if thunit to the photoactivators is expected if the acunit to the photoactivators is expected if the acth th i i t h t it Th hrather than in internanosheet sites Thus, we hrather than in internanosheet sites. Thus, we hphosphors which consist of perovskite-type oxidephosphors which consist of perovskite type oxidethe intrananosheet site and their properties havethe intrananosheet site, and their properties haveNanosheet Phosphor Preparation by Soft Chemical TopotNanosheet Phosphor Preparation by Soft Chemical Topot(  L E Nb O h t)(ex. La0.90Eu0.05Nb2O7 nanosheet)Powder XNew Nanosheet Phosphor Preparation Powder XB lkNew Nanosheet Phosphor PreparationNbO L /E  ( h t ti t  it ) K HBulkNbO6 La/Eu (photoactivator site) K Ht)TBAOHHNO3 unitTBAOH3b. uarby (asity Kens anteKLa0 90Eu0 05Nb2O7 K1-xHxLa0 90Eu0 05Nb2O7 La0 90Eu0 05Nb2O7In0.90 0.05 2 7Using K2CO3, La2O3, 1-x x 0.90 0.05 2 7K of the bulk precursor 0.90 0.05 2 7nanosheetUsing K2CO3, La2O3, Eu O and Nb OK of the bulk precursor was ion exchanged nanosheetThe protonated bulk Eu2O3 and Nb2O5as staring materials  was ion exchanged with H in order to The protonated bulk precursor has been as staring materials, thi  b lk  with H in order to ti t  th  b lk precursor has been t d ith TBAOH this bulk precursor activate the bulk reacted with TBAOH was prepared by precursor for the to exfoliate it into 2010solid state reaction. following soft nanosheets.20102gchemical exfoliation Elemental comp2chemical exfoliation reactionElemental compTGA and ICP-AEreaction. TGA and ICP AEPhotoluminescence Properties of Layered Ph t l iPhotoluminescence Properties of Layered Oxides Before and After Exfoliation PhotolumiOxides Before and After ExfoliationNanoNano(5 2 Bulk Precursors K H La Eu Nb O (5.2 Bulk Precursors K1-xHxLa0.90Eu0.05Nb2O7KLa0.90Eu0.05Nb2O7E T Ot) F2L6 5 D2 K0.08H0.92La0.90Eu0.05Nb2O70.25H2O Eu0.56Ta2O7    L E Nunit0→7 F→5 LF0→5D1La0.90Eu0.05N(K Eu )Taarb. 5 D7 F0 7 FD1→5 Demission excited(K1.5Eu0.5)Taty (aF0F1excitation monitored 0→5 D7 F1 emission excitedat 466 nmensit0→7 F0→7 FF4at 612 nmD3 7 F0Inte5 D05 D0→7 F30→7 F0→5 D5 D0→5 D07 F0)5unit)700650600550500450400350300W l th ( ) arb. uWavelength (nm)ity (aexfoliation tensiexfoliationIntL E Nb O N h texcitationLa0 90Eu0 05Nb2O7 NanosheetsLa0.90Eu0.05Nb2O7 NanosheetsF0→7 F2excitation monitored at 616 nmit)0→7 FD0→excitation monitored at 616 nm. uni5 D0 5emission excitedarb. emission excitedat 353 nmity (→7 F1F4emission excited40350300250tensiD0→0→7 FF3→5 L6→5 D2 emission excitedat 466 nm Further enhaInt 5 D5 D0D0→7F0→F0→Further enhais expected w5 D7 F7 F is expected wh t ti t700650600550500450400350300photoactivat700650600550500450400350300Wavelength (nm)Wavelength (nm)C lConclConclTh l i t h t it ti t d h h LThe novel intrananosheet site activated phosphors La0p p 0.prepared and their photoluminescence properties have beenprepared, and their photoluminescence properties have beenThese nanosheets exhibit photoluminescence emission fromThese nanosheets exhibit photoluminescence emission fromi i f 3 h i iexcitation of Eu3+ or host excitation.excitation of Eu or host excitation.Th i t h t it ti t d h h hibit ffThese intrananosheet site activated phosphors exhibit effecp pcontrary to the direct excitation dominated photoluminescencontrary to the direct excitation dominated photoluminescenAcknowleAcknowleThis research is financially supported by CREST oThis research is financially supported by CREST oi i fi i fescence Characterizations of escence Characterizations of escence Characterizations of escence Characterizations of escence Characterizations of escence Characterizations of id  N h tid  N h tide Nanosheetside Nanosheetside Nanosheetside Nanosheetside Nanosheetside Nanosheetsh  AKATSUKA  Y EBINA  T k hi SASAKIho AKATSUKA, Yasuo EBINA, Takayoshi SASAKIho AKATSUKA, Yasuo EBINA, Takayoshi SASAKIl  M t i l  C tnoscale Materials Center Namiki  Tsukuba  Ibaraki  305-0044  Japan Namiki, Tsukuba, Ibaraki, 305-0044, JapanWA T d hi@ i jWA.Tadashi@nims.go.jptiuctionuctionnosheet-based phosphors consist of Ln ions or Ln-nosheet-based phosphors consist of Ln ions or Ln-transition metal oxide nanosheets Thetransition metal oxide nanosheets. Theosheet site activated phosphors tend to be quiteosheet-site activated phosphors tend to be quitep p qcies such as H O and hydronium ions which actcies, such as H2O and hydronium ions, which act2 yefficient energ transfer from the host nanosheetefficient energy transfer from the host nanosheetgyti t i t d i i t h t itctivators are incorporated in intrananosheet sitesctivators are incorporated in intrananosheet sitesh d t f h t b dhave prepared new types of nanosheet-basedhave prepared new types of nanosheet based3e nanosheets with Eu3+ photoactivator doped ine nanosheets with Eu photoactivator doped ine been characterizede been characterized.Morphology and Singleactic Exfoliation Morphology and Single-t lli  N t  f N h t actic Exfoliation crystalline Nature of Nanosheet yPhosphorsray Diffraction of Phosphors(ex  La Eu Nb O nanosheet)-ray Diffraction of k P(ex. La0.90Eu0.05Nb2O7 nanosheet)k Precursors In plane X ray DiffractionIn-plane X-ray DiffractionK H L E Nb O h t d t 1000 ºCt) 1 00K0.08H0.92La0.90Eu0.05Nb2O7 heated at 1000 ºCLn NbO LnNbO (Ln = La or Eu)unit1 12 0 0Ln1/3-NbO3       LnNbO4       (Ln = La or Eu)rb. u1 0 02y (ar 1sity02 00K H La Eu Nb O dried at 200 ºCnten2 1 02 3 1 00 00 39 nmK0.08H0.92La0.90Eu0.05Nb2O7 dried at 200 Ca=0.38842(9)nm b=a c=1.0438(3)nmIn24 0.39 nma 0.38842(9)nm b a c 1.0438(3)nm0 400 300 200 10 0.400.300.200.10d (nm)( )TEM ObservationK0.08H0.92La0.90Eu0.05Nb2O7·0.25H2O dried at room T TEM Observationa=0.3885(9)nm b=a c=1.2194(3)nmKLa0 90Eu0 05Nb2O7KLa0.90Eu0.05Nb2O7a=0.3904(1)nm b=2.1490(6)nm c=0.3877(1)nm( ) ( ) ( ) 504030 5040302 theta (degree)nanosheet size in-sheet latticepositions were analyzed by2 theta (degree)0.1~1 μm tetragonal  a = 0.4 nmpositions were analyzed byESAFM Ob tiES.AFM Observation3X Y1 06nm32(nm)1.06nm1Height i  f Diff t 04003002001000nanosheet thicknessinescence of Different Distance (nm)nanosheet thicknessObserved by AFM: 2 01(1) nmosheet Phosphors Observed by AFM: 2.01(1) nmEstimation from crystallographic data: 1 06 nmosheet Phosphors ×10-4 M suspensions) Estimation from crystallographic data: 1.06 nm⇒ possible adsorption of oxonium and TBA+ ions, and  ×10 4 M suspensions)possible adsorption of oxonium and TBA ions, and other uncertain factors EX it d @ 619 & EM it d @ 269 other uncertain factors            EX monitored @ 619nm & EM excited @ 269nmNb O EX it d @ 620 & EM it d @ 335Nb2O7   EX monitored @ 620nm & EM excited @ 335nma O EX monitored @ 617nm & EM excited @ 317nmPractical Aspectsa3O10    EX monitored @ 617nm & EM excited @ 317nmPractical AspectsFilm FabricationFilm Fabrication(ex. La0.90Eu0.05Nb2O7 nanosheet)( 0.90 0.05 2 7 )A monolayer film can easily be emission A monolayer film can easily be f b i t d b  L i Bl d tt  fabricated by Langmuir-Blodgett  method.Nanosheet Phosphor PaintNanosheet Phosphor Paint(  (K E )T O h t)(ex. (K1.5Eu0.5)Ta3O10 nanosheet)Nanosheet suspension concentrated by high-Nanosheet suspension concentrated by highspeed (~20000 rpm) centrifugation is viscous speed ( 20000 rpm) centrifugation is viscous enough that it can be painted on a material 75070065060055050045000enough that it can be painted on a material h  l  ith t b i  h d  ncement of  emission intensity Wavelength (nm)such as glass without being shed. ncement of  emission intensity with appropriate with appropriate t t ti  dj t ttor-concentration adjustments.under UV irradiation under room lightin a darkroomunder room lightin a darkroomiusionusionE Nb O E T O d (K E )T O h b90Eu0 05Nb2O7, Eu0 56Ta2O7 and (K1 5Eu0 5)Ta3O10 have been90 0.05 2 7 0.56 2 7 ( 1.5 0.5) 3 10n characterizedn characterized.m the 5D0 to 7F manifold transitions of Eu3+ by either directm the D0 to FJ manifold transitions of Eu by either directti t f f th h t h t t E 3+ thctive energy transfer from the nanosheet hosts to Eu3+ on thegyce emission of their bulk precursorsce emission of their bulk precursors.edgementedgementof the Japan Science and Technology Agencyof the Japan Science and Technology Agency.