P2.4.13 Network of SnO2 nanowires for increased gas sensing performance

Event

14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
Nürnberg/Nuremberg, Germany

Chapter

P2.4 Nanostructured Sensors

Author(s)

E. Brunet, T. Maier, G. Mutinati, S. Steinhauer, A. Koeck - AIT Austrian Institute of Technology GmbH, Molecular Diagnostics, Health & Environment (Austria)

Pages

1538 - 1541

DOI

10.5162/IMCS2012/P2.4.13

ISBN

978-3-9813484-2-2

Price

free

Abstract

A novel gas sensor device based on a network of ultralong tin dioxide (SnO2) nanowires is presented. The nanowire network exhibits a very high surface-to-volume ratio and enables increased gas sensing performance. Two Si-wafers have been coated with SnO2 thin films by spray pyrolysis, glued on a substrate side by side separated by a gap of ~200 µm and annealed in Ar at ~900°C for 1 hour. Ultralong SnO2 nanowires grow from one chip to the other so that an electrical contact is formed between the two chips. The sensing performance of this sensor has been investigated in the presence of H2S and H2. The interconnected network of nanowires has shown a response of 92% to 1.4 ppm H2S at 300°C with a response time below 50 s, which makes the sensor suitable for safety devices. The response to H2 at 300°C has been found to be proportional with the gas concentration up to 100 ppm, which enables a quantitative detection of H2.