A novel method for improving the performance of ZnO gas sensors

A novel ZnO porous nanosolid has been prepared by hydrothermal hot-press method, and the measurements indicated that it had very uniform pore size. Compared with the sensor fabricated from conventional ZnO nanoparticles (denoted as S-1), the sensor from ZnO porous nanosolid (denoted as S-2) showed much better sensing performance towards several organic vapors; the intrinsic resistance of S-2 in air dramatically decreased and its selectivity was improved. The optimum working temperature of S-2 was 370 degrees C, whereas that of S-1 was as high as 420 degrees C. The differences in gas sensing performance between the two kinds of sensors were analyzed based on the scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) measurements. (c) 2005 Elsevier B.V. All rights reserved.