Flexible Calorimetric Gas Sensors for Detection of arnBroad Concentration Range of Gaseous HydrogenrnPeroxide: A Step Forward to Online Monitoringrnof Food-Package Sterilization Processes

摘要

In this study, flexible calorimetric gas sensors are developed for specificrndetection of gaseous hydrogen peroxide (H2O2) over a wide concentrationrnrange, which is used in sterilization processes for aseptic packaging industry.rnThe flexibility of these sensors is an advantage for identifying the chemicalrncomponents of the sterilant on the corners of the food boxes, so-called “coldrnspots”, as critical locations in aseptic packaging, which are of greatrnimportance. These sensors are fabricated on flexible polyimide films byrnmeans of thin-film technique. Thin layers of titanium and platinum have beenrndeposited on polyimide to define the conductive structures of the sensors. Torndetect the high-temperature evaporated H2O2, a differential temperature setuprnis proposed. The sensors are evaluated in a laboratory-scaled sterilizationrnsystem to simulate the sterilization process. The concentration range of thernevaporated H2O2 from 0 to 7.7% v/v was defined and the sensors havernsuccessfully detected high as well as low H2O2 concentrations with arnsensitivity of 5.04 u0001C/% v/v. The characterizations of the sensors confirmrntheir precise fabrication, high sensitivity and the novelty of low H2O2rnconcentration detections for future inline monitoring of food-packagernsterilization.