Title: | Temporally resolved thermal desorption of volatile organics from nanoporous silica preconcentrator |
Author(s): | Winter W; Day C; Prestage J; Hutter T; |
Address: | "SensorHut Ltd, Cambridge, UK. tanya.hutter@utexas.edu" |
ISSN/ISBN: | 1364-5528 (Electronic) 0003-2654 (Linking) |
Abstract: | "Detection and separation of gas-phase volatile organic compounds (VOCs) is of great importance for many applications including air quality monitoring, toxic gas detection and medical diagnostics. A lack of small and low-cost detectors limits the potential applications of VOC gas sensors, especially in the areas of consumer products and the 'Internet of Things'. Most of the commercially available low-cost technologies are either only capable of measuring a single VOC type, or only provide a total VOC concentration, without the ability to provide information on the nature or type of the VOC. We present a new approach for improving the selectivity of VOC detection, based on temporally resolved thermal desorption of VOCs from a nanoporous material, which can be combined with any existing VOC detector. This work uses a nanoporous silica material that adsorbs VOC molecules, which are then thermally desorbed onto a broadband VOC detector. Different VOCs are desorbed at different temperatures depending on their boiling point and affinity to the porous surface. The nanoporous silica is inert; VOC adsorption is proportional to the concentration of VOC in the environment, and is fully reversible. An example of a detection system using a commercial total VOC photoionization detector and a nanoporous silica preconcentrator is demonstrated here for six different VOCs, and shows potential for discrimination between the VOCs" |
Notes: | "PubMed-not-MEDLINEWinter, William Day, Coco Prestage, Joshua Hutter, Tanya eng England 2020/11/10 Analyst. 2021 Jan 4; 146(1):109-117. doi: 10.1039/d0an01822h" |