Optical properties of a azo-dye attached on the surface of the monodisperse silica
photonic crystal have been investigated. The azo-chromophore was covalently attached to a
3-isocyanatopropyl triethoxysilane (ICPTES) having isocynate functional group by a
urethane bond formation reaction. The resulting disperse red/ICPTES (DRICP) was attached
on the surface of the silica photonic crystal by hydrolysis and condensation reactions. The
FTIR spectrum of the resulting product DRICP/silica sphere (DRICPSS) shows no
characteristic isocynate absorption peak at 2270 cm<sup>-1</sup> and shows a new absorption peat at
1700 cm<sup>-1</sup> corresponding the C=O stretching vibration. This result indicates the complete
reaction between –N=C=O and –OH. The DRICPSS has weak brownish color when it is
dried. The color of the DRICPSS changed to intense red when it is wetted in methanol,
ethanol and 2-propanol. The near infrared absorption maximum at 788 nm shifted to 718 nm
for the ICPDRSS after wetting in methanol. This system can be applicable to a sensitive
alcohol sensor.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Citation
Byoung-Ju Kim and Kwang-Sun Kang
"Optical properties of azo-chromophore attached on the surface of a silica photonic crystal", Proc. SPIE 8564, Nanophotonics and Micro/Nano Optics, 85640K (November 20, 2012); doi:10.1117/12.999810; http://dx.doi.org/10.1117/12.999810
