Characterization and organic vapor sensing properties of Langmuir-Blodgett film using perylendiimide material

LB thin film characterization and vapor sensing applications of 1,7-dibromo- N,N’-(bicyclohexyl)-3,4:9,10- perylendiimide (FY3) materials are reported in this study. The thin film deposition conditions of FY3 materials, which are prepared by LB film technique, are characterized by UV-vis spectroscopy and Quartz Crystal Microbalance (QCM) techniques. The typical frequency shift per layer is obtained as 50.15 Hz / layer and the deposited mass onto a quartz crystal is calculated as 399.36 ng / layer (1.50 ng mm^-2). Vapor sensing properties of these LB films against three different volatile organic compounds (chloroform, benzene and toluene) are studied using the QCM technique. The sensitivities to vapors are determined between 3.62 x 10^-4 and 1.60 x 10^-4 Hz ppm^-1. FY3 LB film is more sensitive to chloroform than other vapors. Responses of the FY3 LB film to these vapors are fast, large and reversible. Detection limits are calculated between 0.83 x 10⁴ and 1.88 x 10⁴ ppm. It can be concluded that this FY3 material is promising as a vapor sensing device at room temperature.