Figure 1.

Selective benzene sensing enabled by catalytic WO₃ filter. Chemoresistive response of Pd/SnO₂ to 1 ppm benzene, m‐xylene, toluene, acetone, acetaldehyde, isoprene, methanol, ethanol, CO, hydrogen, and ethylbenzene when prescreened by a) inactive (i.e., at room temperature; Figure S3a, Supporting Information) and b) active (240 °C) catalytic WO₃ packed bed at 50% RH. c) Responses to 1 ppm toluene, m‐xylene and benzene at 10–80% RH. d) Sensor resistance upon exposure to 25–1000 ppb benzene as single analyte (solid line) and in mixtures with 1 ppm (each) toluene and m‐xylene (dashed line). e) Corresponding mixture benzene (green), toluene (red) and m‐xylene (blue) concentrations at the packed bed's outlet measured by PTR‐ToF‐MS. Note that the lines for toluene and m‐xylene are overlapping. f) Sensor responses to 15–5000 ppb of benzene alone (circles) and in mixtures with 1 ppm (each) toluene and m‐xylene (stars), as well as with five interferants (toluene, m‐xylene, acetaldehyde, CO, acetone, each 1 ppm, triangle). Error bars at 1 ppm benzene in (b) and (f, hidden behind symbol) correspond to n = 3 identically produced WO₃ filters and Pd/SnO₂ sensors.