Chiral Liquid Crystals as Sensors for Volatile Organic Compounds, Studied by Means of Optical Microscopy and Light Scattering

Chiral liquid crystals (CLCs) of different viscosities and compositions were studied as promising sensors of volatile organic compounds (VOCs). CLCs were prepared and used as the mixtures of glassy-forming liquid crystals and low molar mass liquid crystals. Experimental methods of studying structural transformations of the surface of CLCs included microscopic observations, spectrophotometry, laser light scattering, and IR spectroscopy. In a previous publication, we discovered that the selectivity of response to different VOCs can be manipulated by different viscosities and the ability to form hydrogen bonds. This study not only confirms previous findings but also suggests the new model of different structural transformations of CLC's surfaces. It was also shown that light scattering is a powerful tool for detecting VOCs at much lower concentrations than it was previously possible.