Dr. Syed Arshad Hussain Wellcomes You


PhD thesis submission
August 8, 2012, 1:37 am
Filed under: Layer-by-Layer (LbL) films, layer-by-layer films, Student

Md Nurul Islam submitted his PhD thesis to Tripura University for PhD degree. Mr Islam did his pre-PhD research work in the Thin Film and Nanoscience Laboratory, Department of Physics, Tripura University.

Title of the thesis: Photo physical characterizations of organized molecular assemblies in ultrathin films fabricated by Langmuir-Blodgett (LB) and Layer by Layer (LbL) self assembled (SAM) techniques.

PhD Supervisor: Dr. S. A. Hussain, Asst Professor, Dept. of Physics, TU.

At present Mr Islam is working as Asst Prof. at Govt. Degree college, Tripura.



My recent paper at Elsevier Journal

Title: Preparation and characterization of an anionic dye–polycation molecular films by electrostatic layer-by-layer adsorption process

D. Dey1, S. A. Hussain1, R. K. Nath2 and D. Bhattacharjee1
1. Department of Physics, Tripura University, Suryamaninagar 799130, Tripura, India
2. Department of Chemistry, Tripura University, Suryamaninagar 799130, Tripura, India Journal: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Abstract:
This communication reports the formation and characterization of self-assembled films of a low molecular weight anionic dye amaranth and polycation poly(allylamine hydrochloride) (PAH) by electrostatic alternating layer-by-layer (LBL) adsorption. It was observed that there was almost no material loss occurred during adsorption process. The UV–vis absorption and fluorescence spectra of amaranth solution reveal that with the increase in amaranth concentration in solution, the aggregated species starts to dominate over the monomeric species. New aggregated band at 600 nm was observed in amaranth–PAH mixture solution absorption spectrum. A new broad low intense band at the longer wavelength region, in the amaranth–PAH mixture solution fluorescence spectrum was observed due to the closer association of amaranth molecule while tagged into the polymer backbone of PAH and consequent formation of aggregates. The broad band system in the 650–750 nm region in the fluorescence spectra of different layered LBL films changes in intensity distribution among various bands within itself, with changing layer number and at 10 bilayer LBL films the longer wavelength band at 710 nm becomes prominent. Existence of dimeric or higher order n-meric species in the LBL films was confirmed by excitation spectroscopic studies. Almost 45 min was required to complete the interaction between amaranth and PAH molecules in the one-bilayer LBL film.

Keywords: Adsorption; Deposition process; Multilayer; Layer-by-layer (LBL) self-assembled films; UV–vis absorption and fluorescence spectroscopy
Full text link: click here