CuO nanosheets, Cr-doped CuO nanosheets, and Cr-doped CuO nanorods were prepared by heating a slurry containing Cu-hydroxide/Cr-hydroxide. Their responses to 100 ppm NO(2), C(2)H(5)OH, NH(3), trimethylamine, C(3)H(8), and CO were measured. For 2.
View Article and Find Full Text PDFVarious ZnO nanostructures such as porous nanorods and two hierarchical structures consisting of porous nanosheets or crystalline nanorods were prepared by the reaction of mixtures of oleic-acid-dissolved ethanol solutions and aqueous dissolved Zn-precursor solutions in the presence of NaOH. All three ZnO nanostructures showed sensitive and selective detection of C(2)H(5)OH. In particular, ultra-high responses (R(a)/R(g) = ∼1,200, R(a): resistance in air, R(g): resistance in gas) to 100 ppm C(2)H(5)OH was attained using porous nanorods and hierarchical structures assembled from porous nanosheets, which is one of the highest values reported in the literature.
View Article and Find Full Text PDFUltra-fast responding and recovering C(2)H(5)OH sensors were prepared using nanoscale SnO(2) hollow spheres with NiO-functionalized inner walls. The exceptional ultra-fast recovery characteristics were attributed to the catalytic surface reaction assisted by NiO at the inner shell.
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