Thin liquid crystal film for corrosion sensing

Abstract

The anchoring energy of Liquid Crystals (LCs) is influenced by several parameters. Many scientists have exploited LCs anchoring in order to develop several LC based optical sensors. This paper proposes and proves a new principle of operation for corrosion sensing based on the anchoring energy of liquid crystals. For the work of this paper 5CB (4-cyano-4-n-pentylbiphenyl) nematic LCs were used to coat iron substrates forming films of about 7 µm thickness. Both corroded and non-corroded iron substrates were coated and the differences in LC anchoring between the two substrates are reported. These differences were studied experimentally using the atomic force microscope (AFM) and the laser profilometer.