Publication Details

Category Text Publication
Reference Category Journals
DOI 10.3390/s20102814
Licence creative commons licence
Title (Primary) Application of low-cost electrochemical sensors to aqueous systems to allow automated determination of NH3 and H2S in water
Author Cämmerer, M.; Mayer, T.; Penzel, S.; Rudolph, M.; Borsdorf, H. ORCID logo
Source Titel Sensors
Year 2020
Department MET
Volume 20
Issue 10
Page From art. 2814
Language englisch
Supplements https://www.mdpi.com/1424-8220/20/10/2814/s1
Keywords chemical sensors; humidity; water quality
Abstract

Usage of commercially available electrochemical gas sensors is currently limited by both the working range of the sensor with respect to temperature and humidity and the spikes in sensor response caused by sudden changes in temperature or humidity. Using a thermostatically controlled chamber, the sensor response of ammonia and hydrogen sulfide sensors was studied under extreme, rapidly changing levels of humidity with the aim of analyzing nebulized water samples. To protect the sensors from damage, the gas stream was alternated between a saturated gas stream from a Flow Blurring® nebulizer and a dry air stream. When switching between high and low humidity gas streams, the expected current spike was observed and mathematically described. Using this mathematical model, the signal response due to the change in humidity could be subtracted from the measured signal and the sensor response to the target molecule recorded. As the sensor response is determined by the model while the sensor is acclimatizing to the new humid conditions, a result is calculated faster than that by systems that rely on stable humidity. The use of the proposed mathematical model thus widens the scope of electrochemical gas sensors to include saturated gas streams, for example, from nebulized water samples, and gas streams with variable humidity.

Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=23127
Cämmerer, M., Mayer, T., Penzel, S., Rudolph, M., Borsdorf, H. (2020):
Application of low-cost electrochemical sensors to aqueous systems to allow automated determination of NH3 and H2S in water
Sensors 20 (10), art. 2814 10.3390/s20102814