NS  Vol.2 No.4 , April 2010
Interfacial control on microstructure, morphology and optics of beta-AgI nanostructures fabricated on sputter-disordered Ag-Sn bilayers
Abstract: We report for the first time a non-template based facile growth of hexagonal (β) AgI nanorods and nanoplates easily fabricated by rf magnetron sputtering on Ag/Sn bilayers upon controlled iodination. The structural and morphological evolution of the β-AgI nanostructures is cha-racterized by X-Ray Diffraction, Atomic Force Microscopy and optical spectroscopy. Sput-tering induced disorder in precursor Ag films, high external stress and high defect concentra-tions at the Sn-AgI interface particularly facili-tates the development of layered hexagonal structure of β-AgI nanostructures. Extremely sensitive room temperature optical absorbance involving evolution of W1,2 and W3 exciton tran-sitions and emission spectra involving phonon replica corroborate the formation of β-AgI na-nostructures with high defect concentrations, are aimed at improving the efficiency of photo-graphic process and looking at microelec-trodic and optoelectronic applications.
Cite this paper: Mohan, D. and Sunandana, C. (2010) Interfacial control on microstructure, morphology and optics of beta-AgI nanostructures fabricated on sputter-disordered Ag-Sn bilayers. Natural Science, 2, 368-372. doi: 10.4236/ns.2010.24044.

[1]   Liang, C., Terabe, K., Tsuruoka, T., Osada, M., Hase-gawa, T. and Aono, M. (2007) AgI/Ag heterojunction nanowires: Facile electrochemical synthesis, and en-hanced ionic conductivity. Advanced Functional Materi-als, 17(9), 1466-1472.

[2]   Lee, W., Yoo, H.-L. and Lee, J.-K. (2001) Template route toward a novel nanostructured superionic conductor film. Chemical Communications, 2001(24), 2530-2531.

[3]   Guo, Y., Lee, J. and Maier, J. (2006) Preparation and characterization of AgI nanoparticles with controlled size, morphology and crystal structure. Solid State Ionics, 177(26-32), 2467-2471.

[4]   Guo, Y.-G., Hu, Y.-S., Lee, J.-S. and Maier, J. (2006) High-performance rechargeable all-solid-state silver bat-tery based on superionic AgI nanoplates. Electrochemis-try Communications, 8(7), 1179-1184.

[5]   El-Kouedi, M., Foss, C.A.Jr., Bodolosky-Bettis, S.A. and Bachman, R.E. (2002) Structural analysis of AgI and Au/AgI nanocomposite films by powder x-ray diffraction: Evidence for preferential orientation. Journal of Physical Chemistry B, 106(29), 7205-7209.

[6]   Xu, S. and Lee, Y. (2003) Different morphology at dif-ferent reactant molar ratios: Synthesis of silver halide low-dimensional nanomaterials in microemulsions. Journal of Material Chemistry, 13(1), 163-165.

[7]   Validzic, I.L., Jankovic, I.A., Mitric, M., Bibic, N. and Nedeljkovic, J.M. (2007) Growth and quantum confinement in AgI nanowires. Materials Letters, 61(16), 3522-3525.

[8]   Validzic, I.L., Jokanovic, V., Uskokovic, D.P. and Ne-deljkovic, J.M. (2008) Influence of solvent on the struc-tural and morphological properties of AgI particles pre-pared using ultrasonic spray pyrolysis. Materials Chem-istry and Physics, 107(1), 28-32.

[9]   Chandra, S. (1981) Superionic solids: Principles and appli-cations. North-Holland Publishing Company, Amsterdam.

[10]   Mochizuki, S. and Fujishiro, F. (2003) Shallow and deep excited states of mesocopic structure in AgI-γAl2O3 composites. Physica Status Solidi (c), 0(2), 763-766.

[11]   Mohan, D.B. and Sunandana, C.S. (2007) AgI nanos-tructure development in sputter-disordered and Al-doped Ag films probed by XRD, SEM, optical absorption and photoluminescence. Applied Physics A, 86(1), 73-82.

[12]   Mohan, D.B. and Sunandana, C.S. (2004) Nanophases in mechanochemically synthesized AgI-CuI system: Struc-ture, phase stability and phase transition. Journal of Physics and Chemistry of Solids, 65(10), 1669-1677.

[13]   Kuiry, S.C., Roy, S.K. and Bose, S.K. (1997) Influence of short circuiting on the kinetics and mechanism of io-dide film growth on Ag and Cd-doped Ag. Metallurgical and Materials Transactions B, 28(6), 1189-1198.

[14]   Mohan, D.B. and Sunandana, C.S. (2006) Iodization of rf sputter induced disordered Ag thin films reveals volume plasmon-exciton “transition”. Journal of Applied Physics, 100(6), 4314.

[15]   Mohan, D.B. and Sunandana, C.S. (2005) Effect of Sn doping on the growth and optical properties of AgI na-noparticles. Journal Nanoscience and Nanotechnology, 5(9), 1-5.

[16]   Guo, Y.J., Lee, J.-K. and Maier, J. (2005) AgI nanoplates with mesoscopic superionic conductivity at room tem-perature. Advanced Materials, 17(23), 2815-2819.

[17]   Vook, R.W. and Witt, F. (1965) Structure and annealing behavior of metal films deposited on substrates near 80°K: I. copper films on glass. Journal of Vacuum Science and Technology, 2(1), 49-57.

[18]   Dayal, P.B., Mehta, B.R., Aparna, Y. and Shivaprasad, S.M. (2002) Surface-mediated structural transformation in CdTe nanoparticles dispersed in SiO2 thin films. Ap-plied Physics Letters, 81(22), 4254-4256.

[19]   Mohan, D.B., Sreejith, K. and Sunandana, C.S. (2007) Surface plasmon-exciton transition in ultra-thin silver and silver iodide films. Applied Physics B, 89(1), 59-63.

[20]   Economou, E.N. (1969) Surface plasmons in thin films. Physical Review, 182(2), 539-554.

[21]   Cardona, M. (1963) Optical properties of the silver and cuprous halides. Physical Review, 129(1), 69-78.

[22]   Mochizuki, S. and Fujishiro, F. (2003) Structural, elec-trical and optical studies on AgI-anatase composites. Journal of Physics: Condensed Matter, 15(29), 5057-5072.

[23]   Kumar, P.S. (2002) Ionic and mesoscopic aspects of cation stabilized silver iodide. Ph.D Thesis, University of Hyderabad, Hyderabad, India.

[24]   Kumar, P.S. and Sunandana, C.S. (2002) Steady-state photoluminescence characteristics of Sb-doped AgI thin films. Nano Letters, 2(9), 975-978.