Optical characterization and organic vapor sensing application of perylendiimide Langmuir-Blodgett thin films

Abstract

The Langmuir-Blodgett (LB) technique was employed to produce thin LB films using N,N'-(glycine tert-butylester)-3,4,9,10-perylenediimide (FY1) material on gold coated glass. The characteristics of the perylenediimide FY1 LB films are assessed by surface plasmon resonance (SPR) measurements. The experimental SPR data are fitted using the Winspall software to evaluate the film thickness and refractive index of this material. Thickness of LB films were determined to be 0.66 +/- 0.07 nm per monolayer of FY1, and the refractive index value of FY1 was obtained as 1.41 +/- 0.06. FY1 LB thin film sensor element was exposed to chloroform, benzene and toluene vapors. Results show that the response of the FYI film to chloroform was the largest among organic vapors with the photodetector response change, Delta I-rf value of 0.082 au. It can be proposed that these LB films have good sensitivity and selectivity for saturated chloroform vapor.