Ju Chan Yang

Significant enhancement of the sensing characteristics of In2O3 nanowires by functionalization with Pt nanoparticles.

We report a significant enhancement in the gas sensing properties of In(2)O(3) nanowires by functionalizing their surfaces with Pt nanoparticles. For Pt-functionalization, In(2)O(3)-Pt core-shell nanowires are synthesized by the sputtering deposition of Pt layers on bare In(2)O(3) nanowires. Next, continuous Pt shell layers are transformed into Pt nanoparticles of cubic phase by heat treatment. In an O(2) gas sensing test, the Pt-functionalized In(2)O(3) nanowires reveal exceptionally higher sensitivity and faster response than bare In(2)O(3) nanowires.

Fabrication and Characteristics of β-Bi2O3 Nanowires Prepared by Heating a Mixture of In and Bi Powders

We studied the characteristics of tetragonal β-Bi 2 O 3 nanowires synthesized by heating a mixture of Bi and In powders. Sufficient growth time and In powder ratio are required for the generation of nanowires. Based on our observations, we propose a Au-catalyzed vapor-liquid-solid process as the dominant growth mechanism, in which In powder affects the morphology of nanowires. Photoluminescence (PL) analysis indicates that the nanowires exhibit emission bands centered at 1.58, 2.40, and 2.76 eV, regardless of the measurement temperature. The overall PL intensity tends to decrease as the measurement temperature increases.

Temperature-controlled synthesis of In2Ge2O7 nanowires and their photoluminescence properties

By controlling the heating temperature of a mixture of In and Ge powders, we have obtained monoclinic In2Ge2O7 nanowires at 600?700??C, whereas we have produced cubic In2O3 nanowires at 900??C. The In2Ge2O7 nanowires grown at 600??C were terminated by Au-containing nanoparticles, giving evidence that the vapour?liquid?solid model is the major growth mechanism. With the growth process at 700?900??C being dominated by a vapour?solid process, we have discussed the temperature-induced change in growth mechanisms. Photoluminescence measurements at 10?300?K revealed a broad visible emission centred at around 2.5?eV.