Synthesis and photoelectrocatalytic activity of In2O3 hollow microspheres via a bio-template route using yeast templates

• Published in: Dalton transactions : an international journal of inorganic chemistry 2018-01, Vol.47 (3), p.78-715
• Main Authors: Pan, Duo, Ge, Shengsong, Zhang, Xiyu, Mai, Xianmin, Li, Shengyao, Guo, Zhanhu
• Format: Article
• Language: English
• Subjects: Chemical precipitation; Diffuse reflectance spectroscopy; Electron microscopy; Electrons; Fourier transforms; Hydroxyl radicals; Indium oxides; Infrared spectroscopy; Light irradiation; Methylene blue; Microspheres; Photodegradation; Scanning electron microscopy; Spectrum analysis; Spherical shells; X ray photoelectron spectroscopy; X-ray diffraction; X-rays; Yeast
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c7dt03878j

Indium oxide (In 2 O 3 ) hollow microspheres were prepared using yeast as a bio-template with the aid of a precipitation method. The yeast provided a solid frame for the deposition of In(OH) 3 to form the precursor. The resulting In 2 O 3 hollow microspheres were obtained by calcining the precursor at 650 °C. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption isotherms and UV-Vis diffuse reflectance spectroscopy. The results showed that the diameter of the In 2 O 3 hollow microspheres was about 2.0-3.0 μm and the spherical shells were composed of In 2 O 3 nanoparticles with a size of ∼20 nm. The BET specific surface area of the sample was 19.23 m 2 g −1 . The photoelectrocatalytic test results showed that the photoelectrocatalytic degradation efficiency of methylene blue (MB) using In 2 O 3 hollow microspheres as catalysts under visible light irradiation and a certain voltage could reach above 95% after 4 hours, much higher than that of only photodegradation. The enhanced photoelectrocatalytic activity could be attributed to the hydroxyl radicals HO&z.rad; produced by the light irradiation reaction process which could oxidize the electron donors and were beneficial to reducing the recombination of electrons and holes. In 2 O 3 hollow microspheres synthesized using yeast as a bio-template with the aid of a precipitation method have demonstrated higher photoelectrocatalytic activity in degrading methylene blue (MB).