19 February 2014 Structural and optical characterization of fresh water diatoms (Cyclotella sp.): nature's nanoporous silica manufacturing plant
Author Affiliations +
Abstract
Siliceous frustules were extracted from a representative fresh water diatom species (Cyclotella sp.) by treating with aqueous hydrochloric (HCl) acid. The structural characterizations of cleaned frustules were examined by scanning electron microscope (SEM). The microscopy images showed that the diatoms have a regular circular shape and are of almost equal size (average length is 9μm and average width is 3 μm). From energy dispersive X –ray spectroscopy (SEM-EDS) spot analysis it was confirmed that the frustules isolated from diatoms are composed mainly of silicon in the form of amorphous silica (SiO2). The bond information of chemical substances of diatom frustules was carried out at ambient temperature by means of Fourier Transform Infrared (FTIR) Spectroscopy. FTIR spectrum as recorded in transmittance mode showed the characteristic peaks for diatom biosilica, including for Si-O-Si stretching vibration at 1057 and 776 cm-1. Photoluminescence (PL) measurements of diatom frustules were performed at room temperature and it was observed that they emitted strong blue PL centered at 440nm when excited with ultraviolet (UV) radiation.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Nirmal Mazumder, Ankur Gogoi, Alak K. Buragohain, Gazi A. Ahmed, Amarjyoti Choudhury, "Structural and optical characterization of fresh water diatoms (Cyclotella sp.): nature's nanoporous silica manufacturing plant", Proc. SPIE 8996, Quantum Dots and Nanostructures: Synthesis, Characterization, and Modeling XI, 89960Y (19 February 2014); doi: 10.1117/12.2039793; https://doi.org/10.1117/12.2039793
PROCEEDINGS
8 PAGES


SHARE
Back to Top