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Synthesis and Characterization of Rare Earth Nanomaterials and their Biological and Photonic Applications Dhiraj Sardar Department of Physics University.

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Presentation on theme: "Synthesis and Characterization of Rare Earth Nanomaterials and their Biological and Photonic Applications Dhiraj Sardar Department of Physics University."— Presentation transcript:

1 Synthesis and Characterization of Rare Earth Nanomaterials and their Biological and Photonic Applications Dhiraj Sardar Department of Physics University of Texas at San Antonio March 10 and 11, 2011 Synthesis and Characterization of Rare Earth Nanomaterials and their Biological and Photonic Applications Dhiraj Sardar Department of Physics University of Texas at San Antonio March 10 and 11, 2011 NORTHWESTERN UNIVERSITY NSF - PREM - MRSEC

2 Outline Introduction to Rare Earths Methods Important Facilities Results – Theoretical and Experimental Potential Applications UTSA Physics Department -PREM PREM Students PREM Publications and Acknowledgements

3 Introduction to Rare Earths Electronic Configuration (RE 3+ ) : Incomplete inner 4f N orbital : [Xe]4f N 5s 2 5p 6 ( N=1 13 ) Optical Properties: Strong absorption and fluorescence : Wide range of excitation and emission (UV-VIS-IR) Applications: Lasers, Display, Sensor, Therapy, Biomedical imaging, etc. Energy levels of trivalent rare earths (RE 3+ ) Electron charge distribution in different orbitals for RE ions showing the shielding of 4f electrons by outer 5s and 5p electrons

4 Methods 1. Synthesis Solvothermal/Hydrothermal Precipitation Thermolysis 2. Morphology Characterization XRD, EDX SEM, TEM, STEM AFM 3. Optical Characterization Refractive Index Optical Absorption/Reflection/Scattering Steady State Emission Fluorescence Lifetime Optical Gain Efficiency(Internal, External, Conversion, Slope) FTIR/Raman

5 Important Facilities Laser Research Laboratory Lasers: Argon, Nd:YAG, Ti:Sapphire, Diode (Vis-IR) Cary-14 Spectrophotometer SPEX 1250M Monochromator Cryogenic Cryostat Microscopy Laboratory STEM w/EDX HR-TEM w/EDX AFM Raman XRD JEOL-ARM200F(0.06 nm resolution)

6 RESULTS STEM imaging of the Nd 3+ distribution Nd 3+ :Sc 2 O 3 Blue = Scandium, Red = Oxygen

7 Theoretical (Judd-Ofelt Formalism) (Judd-Ofelt Model) Radiative Quantum Efficiency: A rad =radiative decay rate A nr =nonradiative decay rate Radiative Process: Major Nonradiative Processes: 1.Multiphonon relaxation (A mp ) 2.Energy transfer between ions (A ET ) 3.Hydroxyl content/High frequency vibrational groups (A OH ) 4.Impurity (A imp ) 4 I 9/2 4 I 11/2 4 I 13/2 4 I 15/2 980nm Pump A mp A OH A ET 1550nm 550nm 650nm 4 S 3/2 4 F 7/2 4 F 9/2 Er 3+

8 Nd 3+ :Y 2 O 3 in HEMA Nd 3+ :Y 2 O 3 Ceramic Polymer embedded samples yield similar spectral features to polycrystalline ceramic sample Nd 3+ :Y 2 O 3 in Epoxy Nd 3+ :Y 2 O 3 Absorptions from Ceramic and Embedded in Polymers

9 RE 3+ :Y 2 O 3 Emissions from Nanoparticles NanoparticlesEpoxy embedded Eu 3+ :Y 2 O 3 Nd 3+ :Y 2 O 3

10 Comparative Results of Nd 3+ in polymer, ceramic, and single crystals ParameterHEMA a Epoxy b Ceramic c Ceramic d Crystal e Crystal f 2 ( cm 2 ) ( cm 2 ) ( cm 2 ) rad (ms) fl (ms) * Q(%) *Internal radiative quantum efficiency a,b,c Sardar et al., Polymer Internationa (2005), J. Appl Phys. (2004, 2005) d Kumar et al., IEEE J Quant. Elect.(2006) E Kaminskii, Laser Crystals, (1996) f Morrison et al., J.Chem. Phys (1983)

11 Other RE-Doped Materials and their Potential Applications Transparent Nd:YAG Ceramic Eu:Y 2 O 3 :HEMA Polymer Yb,Er :Phosphate Glass Inset:Pr :Phosphate Glass Nd:YAG Single Crystal Up and Down Conversion (Imaging, Display, Therapy, Sensing, Security, Lighting, etc.) Eu:Y 2 O 3 nanoparticles (Homogeneous precipitation) Host: La 2 O 2 S Top: 980 nm Ex (10mW) Bottom: 320 nm Ex: YbEr YbTm SrS:EuDy Eu Tb Eu 2+

12 What is so Unique about RE (Nd 3+ ) for Biomedical Applications? Large Stokes shift (~500nm) & strong emission Multi-frequency absorption & emission Long fluorescence lifetimes Optical properties independent of size Nontoxic absorptionemission

13 Imaging Application of RE Nanoparticles Present technology: Organic Dyes and Quantum Dots Advantages-Highly Fluorescent Disadvantages-UV excitation causes autofluorescence, reducing S/N ratio -Size tunability is needed for quantum dots for proper excitation -Toxicity of the composition, Photobleaching Color tunable Q dots AutofluorescenceAfter background subtraction Future technology: Rare Earth-doped Nanoparticles Advantages-Highly Fluorescent, wide range of excitation and emission (UV-IR), no autofluorescence, nontoxic, no size requirement, no photobleaching Confocal image of the 980 nm excited Emissions (550 and 670 nm) from Yb,Er:CaF 2 Nanoparticles ab (a)Live cell (mouse fibroblast) image with green upconversion under 980 nm Exc. (b)Cell autofluorescence under UV Exc.

14 Photodynamic Therapy with IR Upconversion (IPDT) Advantages: IR Upcoversion, 5 times penetration depth compared to Current UV-X PDT

15 Advanced Engineering and Technology (AET) Building ($82.5M; December 2009) –Physics Department occupies the 3 rd floor (over 14,000 sq. ft. of lab space) –$11.2M spent by UTSA to Renovate Physics Research Laboratories Thin Films Laboratory (AET) –ALD, Laser Deposition Biophotonics Research and Imaging Laboratory (AET) Synthesis Labs (AET) –Nanomaterials –Nanophotonics and Laser Materials Terahertz Laboratory (AET) Computational Physics Laboratories (AET) –Access to the Texas Advanced Computing Center (TACC at UT Austin) Advanced Microscopy Laboratory (Science Building) –TEM-STEM, SEM, AFM, Raman –Including the most advanced spherical aberration corrected STEM (JEOL ARM 200F) UTSA Physics Department- PREM Tenure-track faculty Total: 13; PREM: 7 6 Minority; 3 Women 2 Hispanic Women 1 African American Woman

16 UTSA PREM Researchers Dr. Jianhui Yang (2010) Dr. Ajith Kumar (2011) Erik Enrique Joseph Barrios Edward Khachatryan Robert C. Dennis Brian Yust Leland Page Kenneth Ramsey Madhab Pokrhel Nathan Ray Francisco Pedraza Devraj Sandhu Jesse Salas Hector Barron-Escobar Marcus Najera Gilberto Cassilas Garcia Zurab Kereselidze

17 Published or in Press: Chandra, S.*, Francis Leonard Deepak, J. B. Gruber, and D. K. Sardar, Synthesis, Morphology, and Optical Characterization of Er3+:Y2O3, J. Chem. Physics C, 114, (2010). Burdick, G. W., J. B. Gruber, K. L. Nash, and D. K. Sardar, Analyses of 4f11 Energy Levels and Transition Intensities Between Stark Levels of Er3+ in Y3Al5O12, Spectroscopy Letters: 43, (2010). Gruber, J. B., G. W. Burdick, S. Chandra*, and D. K. Sardar, Analyses of the Ultraviolet Spectra of Er3+ in Er2O3 and Er3+ in Y2O3, J. Appl. Phys., 108, : 1-7 (2010). Chandra, S.*, J. B. Gruber, G. W. Burdick, and D. K. Sardar, Material Fabrication and Crystal-Field Analysis of the Energy Levels in Er3+ doped Er2O3 and Y2O3 Nanoparticles Suspended in Polymethyl Methacrylate, J. Appl. Pol. Sci. (in Press) (2011). Yang, J. and D. K. Sardar, One-Pot Synthesis of Coral-Shaped Gold Nanostructures for Surface-Enhanced Raman Scattering, J. Nano Res. (in Press) (2011). Yang, J., R. C. Dennis*, and D. K. Sardar, Room-Temperature Synthesis of Flowerlike Ag Nanostructures Consisting of Single Ag Nanoplates, Mater. Res. Bull. (in Press) (2010). B. Yust*, D. K. Sardar, and A. T. Tsin, "Phase conjugating nanomirrors: utilizing optical phase conjugation for imaging", SPIE Proceedings, Vol (In Press) (2011). Francis Leonard Deepak, Rodrigo Esparza, Belsay Borges, X. Lopez-Lozano, Miguel Jose Yacaman, Rippled and Helical MoS 2 Nanowire catalysts – An aberration corrected STEM study. Catalysis Letters, In Press, Page, L*, Maswadi, S, Glickman, RD, Optoacoustic Spectroscopic Imaging of Radiolucent Foreign Bodies, in Medical Imaging 2010: Ultrasonic Imaging, Tomography, and Therapy, D'hooge, J; McAleavey, SA, Eds., Proc. SPIE, Vol. 7629, pp 7629OE-1 – 7629OE-7, Maswadi*, S, Glickman, RD, Elliott, WR, Barsalou N,. Nano-Lisa for In Vitro Diagnostic Applications, in Photons Plus Ultrasound: Imaging and Sensing 2011, Oraevsky AA, Wang LV, Eds, Proc. SPIE, Vol. 7899, in Press, Page, L*, Maswadi, S, Glickman, RD, Identification of Radiolucent Foreign Bodies in Tissue Using Optoacoustic Spectroscopic Imaging, in Photons Plus Ultrasound: Imaging and Sensing 2011, Oraevsky AA, Wang LV, Eds., Proc. SPIE, Vol. 7899, in Press, Francis Leonard Deepak, G. Casillas-Garcia *, H. Barron*, R. Esparza and M. Jose-Yacaman, New Insights into the structure of Pd-Au nanoparticles as revealed by aberration-corrected STEM, in Press, 2011 V. H. Romero, W. Egido, Z. Kereselidze*, C. M. Valdez,.E. Michaelides, X. G. Peralta, M. Jose-Yacaman, F. Santamaria. Neurons preferentially internalize goldnanostars with strong and precise photothermal properties. Submitted to Nanomedicine NBM, X. G. Peralta, Plasmon modes for terahertz detection: Terahertz Plasmon modes in grating coupled double quantum well field effect transistors, released by LAP Lambert Academic Publishing ( ) - ISBN-13 : (2010). Wilmink, G. J., Rivest, B. D., Roth, C. C., Ibey, B. L., Payne, J. A., Cundin, L. X., Grundt, J. E., Peralta, X., Mixon, D. G. and Roach, W. P., In vitro investigation of the biological effects associated with human dermal fibroblasts exposed to 2.52 THz radiation. Lasers in Surgery and Medicine, n/a. doi: /lsm.20960, J. Antunez-Garcia, S. Mejia-Rosales, E. Perez-Tijerina, J. M. Montejano-Carrizales and M. Jose –Yacaman. Coallescence and collision of gold nanoparticles. Materials, 4: , doi: /ma , Published, 4 other papers submitted, and 11 more under preparation All Publications Acknowledge NSF-PREM Support: Grant No. DMR PREM Publications ( )


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