Wet Chemical Synthesis and Screening of Thick Porous Oxide Films for Resistive Gas Sensing Applications

Abstract

A method of wet chemical synthesis suitable for high throughput and combinatorial applications has been developed for the synthesis of porous resistive thickfilm gas sensors. This method is based on the robot-controlled application of unstable metal oxide suspensions on an array of 64 inter-digital electrodes positioned on an Al 2 O 3 substrate. SnO 2 , WO 3, ZrO 2 , TiO 2 , CeO 2 , In 2 O 3 and Bi 2 O 3 were chosen as base oxides, and were optimised by doping or mixed oxide formation. The parallel synthesis of mixed oxide sensors is illustrated by representative examples. The electrical characteristics and the sensor performance of the films were measured by high-throughput impedance spectroscopy while supplying various test gases (H 2 , CO, NO, NO 2 , propene). Data collection, data mining techniques applied and the best potential sensor materials discovered are presented.

Combinatorial and High‐Throughput Materials Science

“…[340] The authors used automated liquid-phase synthesis for the preparation of porous thick-film sensor materials on 64 electrode arrays. They used HT impedance spectroscopy to study the effects of doped SnO 2 , WO 3 , ZrO 2 , CeO 2 , In 2 O 3 , and Bi 2 O 3 materials on the reponse towards the test gases.…”

Towards Rational Design of Sensing Materials from Combinatorial Experiments

“…Over the last several years, there have been a growing number of reports on data mining in sensing materials (Frenzer et al, 2006;Mijangos et al, 2006;Villoslada and Takeuchi, 2005). "Searching for a needle in the haystack" had been popular in the early days of combinatorial materials science (Jandeleit et al, 1999;Jansen, 2002;.…”

Vascular Access Simplified. A. H. Davies and C. P. Gibbons (eds). 148×209 mm. Pp. 246. Illustrated. 2007. tfm. Publishing Ltd: Shrewsbury. £30·00

“…They combined, for example, different gas‐sensing semiconductors for the rapid analysis of benzene derivatives 339. The composition of a variety of potential electrochemical sensor materials for H 2 , Co, NO, NO 2 , and propene, discovered by HT techniques, has been reported by the research groups of Maier and Simon 340. The authors used automated liquid‐phase synthesis for the preparation of porous thick‐film sensor materials on 64 electrode arrays.…”