Interfacial control on microstructure, morphology and optics of beta-AgI nanostructures fabricated on sputter-disordered Ag-Sn bilayers

D. Bharathi Mohan, C. S. Sunandana

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DOI: 10.4236/ns.2010.24044                

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.

Keywords

Thin Films; Nanostructures; Crystal Structure; Optical Properties

Conflicts of Interest

The authors declare no conflicts of interest.

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