TY  - JOUR
A1  - Kirchner, Patrick
A1  - Reisert, Steffen
A1  - Pütz, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Characterisation of polymeric materials as passivation layer for calorimetric H2O2 gas sensors
JF  - Physica Status Solidi (a)
N2  - Calorimetric gas sensors for monitoring the H₂O₂ concentration at elevated temperatures in industrial sterilisation processes have been presented in previous works. These sensors are built up in form of a differential set-up of a catalytically active and passive temperature-sensitive structure. Although, various types of catalytically active dispersions have been studied, the passivation layer has to be established and therefore, chemically as well as physically characterised. In the present work, fluorinated ethylene propylene (FEP), perfluoralkoxy (PFA) and epoxy-based SU-8 photoresist as temperature-stable polymeric materials have been investigated for sensor passivation in terms of their chemical inertness against H₂O₂, their hygroscopic properties as well as their morphology. The polymeric materials were deposited via spin-coating on the temperature-sensitive structure, wherein spin-coated FEP and PFA show slight agglomerates. However, they possess a low absorption of humidity due to their hydrophobic surface, whereas the SU-8 layer has a closed surface but shows a slightly higher absorption of water. All of them were inert against gaseous H₂O₂ during the characterisation in H₂O₂ atmosphere that demonstrates their suitability as passivation layer for calorimetric H₂O₂ gas sensors.
Y1  - 2012
U6  - http://dx.doi.org/10.1002/pssa.201100773
SN  - 1862-6319
VL  - 209
IS  - 5
SP  - 859
EP  - 863
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Kirchner, Patrick
A1  - Reisert, Steffen
A1  - Schöning, Michael Josef
T1  - Calorimetric gas sensors for hydrogen peroxide monitoring in aseptic food processes
T2  - Gas sensing fundamentals. (Springer Series on Chemical Sensors and Biosensors ; 15)
N2  - For the sterilisation of aseptic food packages it is taken advantage of the microbicidal properties of hydrogen peroxide (H2O2). Especially, when applied in vapour phase, it has shown high potential of microbial inactivation. In addition, it offers a high environmental compatibility compared to other chemical sterilisation agents, as it decomposes into oxygen and water, respectively. Due to a lack in sensory detection possibilities, a continuous monitoring of the H2O2 concentration was recently not available. Instead, the sterilisation efficacy is validated using microbiological tests. However, progresses in the development of calorimetric gas sensors during the last 7 years have made it possible to monitor the H2O2 concentration during operation. This chapter deals with the fundamentals of calorimetric gas sensing with special focus on the detection of gaseous hydrogen peroxide. A sensor principle based on a calorimetric differential set-up is described. Special emphasis is given to the sensor design with respect to the operational requirements under field conditions. The state-of-the-art regarding a sensor set-up for the on-line monitoring and secondly, a miniaturised sensor for in-line monitoring are summarised. Furthermore, alternative detection methods and a novel multi-sensor system for the characterisation of aseptic sterilisation processes are described.
KW  - Calorimetric gas sensor
KW  - Hydrogen peroxide
KW  - Multi-sensor system
Y1  - 2014
SN  - 978-3-642-54518-4 (Print) ; 978-3-642-54519-1 (Online)
U6  - http://dx.doi.org/10.1007/5346_2013_51
SP  - 279
EP  - 309
PB  - Springer
CY  - Heidelberg
ER  -