The measurement data of the calorimetric H2O2 sensor from the
calibration experiment is depicted in Fig. 6. Therefore, the temperature
difference (DT) is plotted vs. the H2O2 concentration for
each one of the parameter combinations of the calibration experiment.
The values of the respective gas temperature are given by
colours (see legend of Fig. 6). The values of humidity (CH2O) varied
between 15.1 and 22.6% v/v but are not further specified (n.s.) for
each individual data point in this plot. The dashed lines were fitted
to the data, in order to illustrate the linear sensor behaviour.
The response of the H2O2 sensor is linear for each set of
parameter combinations at a specific gas temperature (TGas),
regardless of the level of humidity [CH2O]. On the other hand, the
sensor has a strong dependence on the gas temperature. In fact, the
same behaviour has been found in previous measurements (Reisert
et al., 2010). This phenomenon may be explained by the expansion
of the carrier gas with increasing temperature. Assuming constant
pressure in the measuring chamber, the volume increases proportionally
to the gas temperature. At that time the number density of
H2O2 molecules in the gas stream decreases, thus lowering the rate
of a reaction at the sensor surface. To overcome this problem, a
temperature compensation of the sensor signal can be done. For
this purpose, the temperature behaviour of the sensor must be
considered in more detail. Therefore, the obtained temperature