Mo-CHS-02 - Humidity Enhances the Isopropyl Alcohol Detection by Co-Mn Oxide

Event
EUROSENSORS 2026
2026-09-06 - 2026-09-09
Zurich
Band
Poster
Chapter
Chemical Sensors
Author(s)
R. dos Santos Theodoro, D. P. Volanti - São Paulo State University,São José do Rio Preto (Brazil), M. D’Andria, A. T. Güntner, M. Pereira Martins - ETH Zurich,Zurich (Switzerland)
Pages
392 - 393
DOI
10.5162/eurosensors2026/Mo-CHS-02
ISBN
978-3-910600-12-6
Price
free

Abstract

Humidity is a major challenge in metal oxide-based gas sensing, often compromising sensor performance and reliability.[1] Here, we report a p-type cobalt–manganese mixed oxide for the detection of isopropyl alcohol (IPA) at ppb-level concentrations under humid conditions. The sensing material was synthesized by flame spray pyrolysis.[2] Structural and morphological characterization was performed by X-ray diffraction and scanning electron microscopy (SEM). The sensor response to 1000 ppb IPA was evaluated at 310 °C under relative humidity levels ranging from 0 to 90%. Remarkably, the presence of humidity enhanced the sensor response, indicating a positive contribution of surface-adsorbed hydroxyl groups to the interaction with IPA. At 90% RH and 300 °C, the sensor achieved experimental and theoretical limits of detection (LODs) of 15.6 ppb and 53.4 ppt, respectively. These findings demonstrate that water vapor does not necessarily act as an interfering species but can promote VOC sensing. The Co–Mn oxide therefore offers a promising strategy for humidity-tolerant gas sensors targeting real-world applications.