Sensors hydrogen sulphide

An alternative approach, adopted by Albery et al. [59-61], is to determine the mechanism giving rise to the sensor response and to use this information together with the measured data at short times to calculate the final response. This was used for an electrochemical sensor system incorporating cytochrome oxidase where the steady-state responses of the measurement system were insufficiently fast for useful measurement of respiratory inhibitors such as cyanide, hydrogen sulphide, etc. By using mechanistic information, it was possible to successfully calculate the concentration in a test sample by real-time analysis of the sensor signals at short times after exposure to the test sample. The analysis could cope with the gradual loss of enzyme activity commonly found in these biosensor devices. 

Several types of gas-sensitive MOS devices have been developed since 1975. Already sensors for hydrogen, ammonia, hydrogen sulphide, ethanol vapour, arsine and carbon monoxide have been developed. The devices have the... 

Chen Z, Lu C (2005) Humidity sensors a review of materials and mechanisms. Sensor Lett 3 274-295 Choi MMF, Hawkin P (2003) Development of an optical hydrogen sulphide sensor. Sens Actuators B 90 211-215 Chou J (2000) Hazardous gas monitors a practical guide to selection, operation and apphcation. McGraw-HiU, New York Cleaver KD (2001) The analysis of process gases a review. Accred Qual Assur 6(1) 8-15... 

Figure 6. AC (1 kHz) resistivity changes at room temperature for a conducting polypyrrole sensor exposed to eight 15 minute pulses of 0.1% hydrogen sulphide in air over a period of 4 hours.

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