Synthesis, photocatalysis, and gas-sensing property of monodisperse In2O3 hollow spheres by template implantation.

• Main Authors: Tzu-Tsung Tseng, 曾子聰
• Other Authors: 曾文甲
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/42386672421852920720

博士 === 國立中興大學 === 材料科學與工程學系所 === 99 === Indium oxide (In2O3) microspheres with hollow interiors have been prepared by a facile implantation route which enables indium ions released from indium-chloride precursors to chelate with and implant into nonporous polymeric templates in C2Cl4 solvent at 75 oC. The templates are then removed upon calcination at 500oC in air atmosphere, forming monodisperse hollow In2O3 particles of bcc structure which have a high surface area (260m2g-1). The particle size and shell structure of hollow sphere can be altered by synthesis parameter (e.g., InCl3 concentration, reaction time and reaction temperature). For example, average particle size of the hollow particles is increased from 500 nm (InCl3 0.01g) to 1μm (InCl3 0.1g), as well as the specific surface area from 15.1 to 260m2g-1, and pore volume from 0.44 to 0.05cm3g-1. For the hollow In2O3 particles with a high surface area (54.7 m2 g-1), an enhanced photocatalytic efficiency (up to ~ one-fold increase) against methylene blue (MB) dye is obtained under UV exposure for the aqueous In2O3 colloids with a dilute solids concentration of 0.02 wt.%. The surface area of hollow In2O3 particles is also an important index for CO gas sensing property. Gas sensitivity is raised from 15 to 42% with increasing surface area (15.1 to 260 m2g-1).