Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (09): 2455-2460.doi: 10.3866/PKU.WHXB20100909

• CATALYSIS AND SURFACE STRUCTURE • Previous Articles     Next Articles

Preparation of Au@TiO2 Catalyst Using Escherichia Coil as the Template and Its Oxidation Reaction Activity toward CO

LIU Yu-Liang, YOU Cui-Rong, LI Yang, HE Tao, ZHANG Xiang-Qin, SUO Zhang-Huai   

  1. Chemistry and Biology College, Yantai University, Yantai 264005, Shandong Province, P. R. China
  • Received:2010-03-17 Revised:2010-06-21 Published:2010-09-02
  • Contact: SUO Zhang-Huai E-mail:zhsuo@ytu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20473070, 20973148).

Abstract:

Many microorganisms can adsorb metal ions strongly and even reduce them to their metal states. We studied the adsorption of gold nanoparticles on Escherichia coil (DH5α) to form Au@DH5α. Titanium tetrabutoxide was added to Au@DH5αto prepare Au@DH5α-Ti(OH)4 by hydrolysis. The DH5αtemplate was removed by calcination in air to obtain the Au@TiO2 catalyst. These materials were characterized by N2 adsorption, X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), thermogravimetry-differential thermal analysis (TG-DTA), and transmission electron microscopy (TEM). The results show that the gold catalyst maintains a rod-like structure similar to DH5αand the porous structure of the titanium oxide prepared using DH5αas a biological template can prevent the aggregation of gold nanoparticles to some extent. With higher amounts of DH5αdosage, smaller gold nanoparticles were obtained and the surface plasmon absorption of gold nanoparticles shifted toward shorter wavelengths. The obtained gold catalyst has a larger surface area than the catalyst prepared by the impregnation method. However, this increases the coke content of the catalyst. Catalytic activity was evaluated by the CO oxidation reaction. We found that with a DH5αdosage of 100 or 150 mL, the obtained gold catalyst can convert CO to CO2 completely at 80 ℃.

Key words: Titaniumoxide, Escherichia coil, Template agent, Gold catalyst, CO oxidation