To control or monitor processes and the compliance with air quality regulation, highly selective and long‐term stable gas sensors with a high accuracy in the low ppm detection range are needed. Gas sensor techniques detecting the actual concentration of analyte species often suffer from inaccuracy at low concentrations and signal instability. In contrast, gas sensors detecting the cumulative analyte amount during the measurement period are beneficial for monitoring very small amounts. The idea of the cumulative detection principle is the accumulation of the gas molecules in the sensitive layer and therefore measuring the timely integrated concentration of the gas species (“the amount”). Hence, the sensitive layer of the cumulative sensor consists of a gas storage material, which is able to store selectively the analyte molecules via a chemical bonding and thereby changes its electrical properties. In this work, the principle and the benefits of the cumulative detection is described. As an example, measurement results of an integrating NOx sensor developed for the automotive exhaust are shown to demonstrate the general integrating functionality of this cumulative measurement technique.

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