Fabrication of porous Zn2TiO4-ZnO microtubes and analysis of their acetone gas sensing properties

Porous Zn2TiO4-ZnO microtubes have been successfully fabricated using chemical precipitation followed by a calcination process using a carbon fiber template. The porous Zn2TiO4-ZnO microtubes with a diameter of similar to 4 mu m consisted of Zn(2)TiO(4)and ZnO nanoparticles. These displayed worm-like pore structures. Carbon fibers played an important role during the porous Zn2TiO4-ZnO microtube formation process. The porous and hollow structure of Zn2TiO4-ZnO provided abundant active sensing sites and channels for gas adsorption and diffusion. The porous Zn2TiO4-ZnO microtubes exhibited improved gas sensing properties for acetone when compared with pure ZnO. The Zn2TiO4-ZnO sensor response was 33.4 for 100 mu g.ml(-1)acetone at the optimum operating temperature (370 degrees C). This was similar to 2.7 times higher than that of pure ZnO. Additionally, the as-prepared porous Zn2TiO4-ZnO microtubes displayed sufficient long-term acetone stability and selectivity. This showed the potential application for acetone detection. The enhanced Zn2TiO4-ZnO gas sensing properties are due to the unique heterogeneous and porous structure, which was analyzed using the porous and band structure.