Local CuO Nanowire Growth on Microhotplates: In Situ Electrical Measurements and Gas Sensing Application

Stephan Steinhauer (1) , Audrey Chapelle (2) , Philippe Menini (2) , Mukhles Sowwan (1)

1 OIST - Okinawa Institute of Science and Technology Graduate University
2 LAAS-MICA - Équipe MICrosystèmes d'Analyse

We report on local CuO nanowire growth on microhotplates combined with in situ measurement of the electrical resistance for well-controlled integration into conductometric gas sensing devices. Discrete current steps were observed during the CuO nanowire synthesis process, which is attributed to individual nanowire connections being formed. The high gas sensitivity of the CuO nanowire devices was confirmed by detection of carbon monoxide CO in the low-ppm-level concentration range. Furthermore, we demonstrate that CuO nanowire growth inside a gas measurement setup allows studies on gas sensor poisoning/deactivation processes. A significant decrease of CO response was found after controlled exposure to humidity, which suggests sensor deactivation by surface hydroxylation. Thus, our approach could be a novel and simple way for revealing new insights in various gas sensor degradation mechanisms in the future and might also be adapted for different metal oxide nanomaterials.

Mots clés: CuO nanowire; gas sensor; microhotplate; in situ measurement; CO sensing; sensor degradation

Domaines: Micro et nanotechnologies/Microélectronique; Chimie analytique

Stephan Steinhauer, Audrey Chapelle, Philippe Menini, Mukhles Sowwan. Local CuO Nanowire Growth on Microhotplates: In Situ Electrical Measurements and Gas Sensing Application. ACS Sensors, 2016, 1 (5), pp.503-507. ⟨10.1021/acssensors.6b00042⟩. ⟨hal-02045514⟩