Phase transformation (cubic to rhombohedral): the effect on the NO2 sensing performance of Zn-doped flower-like In2O3 structures

• DOI: 10.1039/c3ra47467d
• Publication Date: 2014-02-07T12:07:02Z
• Authors: Pei Li; Huiqing Fan; Yu Cai; Mengmeng Xu; Changbai Long; Mengmeng Li; Shenhui Lei; Xinwei Zou
• Keywords: Trigonal crystal system; Morphology

Cubic In2O3 (bcc-In2O3) was transformed into a mixture of bcc-In2O3 and rhombohedral (rh-In2O3) by Zn doping. The Zn-doped flower-like structures consisted many thin sheets with length 0.4–1 μm, cubes 200 nm, while the size microflowers 1–3.5 μm. doping concentration significantly affected phase transformation overall morphology In2O3. Furthermore, analysis N2 adsorption–desorption measurements showed that (sample S5) adsorbed largest amount had biggest surface area (46.41 m2 g−1), which contributed to an improvement in gas sensing performance. Finally, sensors based on bcc- rh-In2O3 exhibited much higher response NO2 than pure S1), highest 27.4 ± 2.5 for 5 ppm NO2. Thus, performance enhanced transformation.