Chiral Liquid Crystal-Based Sensor for the Detection of Low Humidity

Abstract

The humidity sensing capability of a film of (S)-5-octyloxy-2-[{4-(2-methylbuthoxy)-phenylimino}-methyl]-phenol liquid crystal (LC) was studied. The experimental results show that LC thin film offers a promising perspective as a sensing material for the detection of relatively low humidity levels at even room temperature. It was observed that the operating temperature has a considerable effect on humidity sensing performance of the sensor. A comparison of kinetic models applied to the adsorption of water molecules on the LC film was evaluated for the Ritchie and Elovich kinetic models. Linear regression analysis results show that Elovich equation provides the best correlation for the water molecule adsorption processes.