Introduction of a Pore Connection Network into Mesoporous TiO₂Films to Enhance CO Gas Sensitivity

Abstract

In this work, ordered mesoporous TiO 2 films with interior pore connections were fabricated. To introduce the interior pore connections, the grain growth of TiO 2 on the pore wall structure was controlled by increasing the annealing time. In the annealing process, the growth of TiO 2 grains was enhanced, and interior pores were connected by a meso-channel formed during the growth of TiO 2 grains. As a result, with increasing annealing time, the specific surface area of the mesoporous TiO 2 films increased by a factor of 3, although the porosity decreased. When the ordered mesoporous TiO 2 film with enhanced pore connectivity was applied in a CO gas sensor, the gas sensitivity increased by a factor of almost 20 due to the enhanced pore connectivity resulting from controlled annealing time. The introduction of pore connectivity in a closed pore structure may be an advantageous method in various fields where a large surface area is required for nanoporous structured materials.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.255.6.125 Downloaded on 2015-07-12 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.255.6.125 Downloaded on 2015-07-12 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.255.6.125 Downloaded on 2015-07-12 to IP

Effect of Substrates on Structural Properties of Pure Anatase Phase Titanium Dioxide Thin Films Prepared by Mist Chemical Vapor Deposition

“…Titanium dioxide (TiO 2 ) thin film has attracted considerable interest as a promising sensing material with potential applicability for various thin-film gas sensors due to its outstanding sensing properties, chemical stability and electrical properties. 1,2 There are three crystalline phases of TiO 2 : rutile, anatase and brookite. The thermal stability of brookite phase TiO 2 is poorer than anatase phase and rutile phase TiO 2 , which limits the application of brookite phase TiO 2 .…”