Synthesis and Light Induced Characteristics of Siloxane Substituted Azobenzene: An Application for Optical Storage Device

Abstract

The light induced behaviour of siloxane substituted azobenzene compounds in the presence of alkylene spacers is reported for the first time. Firstly, these photosensitive compounds were synthesized and elucidated the molecular structure by spectral analysis such as NMR, FTIR, and UV/Vis. Photoisomerization effect was evaluated in solution and also in nematic phase. The photosaturation occurred exactly at 29 seconds, whereas thermal back relaxation was observed ranging from 19.8 to 23.8 hours. Long duration of the thermal back relaxation is due to the presence of sterically hindered siloxane group substituted to the azobenzene molecules. Decrease in the duration of cis-trans isomerization was found when the number of alkylene spacers was increased. These siloxane based azobenzene derivatives are useful for the fabrication of optical storage device and molecular switches.

Photo‐induced characteristics of azobenzene based gold nanoparticles

“…Introduction: Currently, sensors, optical storage and molecular switches have a great interest in optically active nanoparticles [1,2]. The E-Z (trans-cis) isomerisation initiates using the irradiation of light energy to the system [3][4][5][6][7]. The π-π* transition takes place in the N = N moiety via UV light (365 nm) illumination.…”

“…This could happen spontaneously without any external aid and the process is called back relaxation (BR). Rapid BR is occurring in the excited molecular system via illumination of ∼450 nm visible light [4][5][6][7]. Nevertheless, BR is very important phenomenon because of its applicability in information storage devices [7][8][9][10].…”

“…Rapid BR is occurring in the excited molecular system via illumination of ∼450 nm visible light [4][5][6][7]. Nevertheless, BR is very important phenomenon because of its applicability in information storage devices [7][8][9][10]. Presently, photo-reactive nanoparticles were employed in many research areas namely, photo-switchable surface wettability, molecular switches, optical storage device and molecular recognition applications [1,2,[5][6][7][8][9][10][11].…”

“…Nevertheless, BR is very important phenomenon because of its applicability in information storage devices [7][8][9][10]. Presently, photo-reactive nanoparticles were employed in many research areas namely, photo-switchable surface wettability, molecular switches, optical storage device and molecular recognition applications [1,2,[5][6][7][8][9][10][11]. Hybrid nanocomposites and nano-matrices; which are obtained from organic and inorganic nanoparticles can be extensively useful in optical nano-devices [8][9][10].…”

“…Hybrid nanocomposites and nano-matrices; which are obtained from organic and inorganic nanoparticles can be extensively useful in optical nano-devices [8][9][10]. Among all the organic light sensitive compounds, azobenzene derivatives have promising photo-switching effect and isomerisation properties [4][5][6][7]. Along with azobenzene compounds, other light sensitive organic compounds such as imines and chalcones are also used for the photo-induced studies [8,10].…”