Surface Enhanced Raman Spectroscopic investigations of 2-bromo-3-methylamino-1,4-naphthoquinone on silver nanoparticles

International audienceSurface Enhanced Raman Spectroscopic technique has been employed to investigate the orientation of 2-bromo-3-methylamino-1,4-naphthoquinone (BMANQ) on silver nanoparticles. Silver nanoparticles have been prepared by solution combustion method with citric acid as fuel. Silver nanoparticles were characterized by X-ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and Scanning Electron Microscopy (SEM). XRD and morphological results confirmed the nanocrystalline nature of the prepared silver nanoparticles. The observed intense C=O stretching, C-Br stretching and NH2 vibration suggests that the BMANQ molecule may be adsorbed in a 'stand-on' orientation to the silver surface. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy show that charge transfer occurs within the molecule. (C) 2014 Elsevier B.V. All rights reserved