Synthesis of CoOx-TiO2 Catalysts and Its Application for Low-Temperature CO Oxidation

Abstract EN

A series of Au/CoOx-TiO2 with various Co/Ti ratios prepared.

CoOx/TiO2 was prepared by incipient wetness impregnation with aqueous solution of cobalt nitrate.

Au catalysts were prepared by deposition-precipitation (DP) method at pH 7 and 338 K.

The catalysts were characterized by inductively coupled plasma-mass spectrometry, temperature programming reduction, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy.

The reaction was carried out in a fixed bed reactor with a feed containing 1% CO in air at weight hourly space velocities of 120,000 mL/h g and 180,000 mL/h g.

High gold dispersion and narrow particle size distribution were obtained by DP method.

The addition of CoOx into Au/TiO2 enhanced the activity of CO oxidation significantly.

Au/5% CoOx-TiO2 had the highest catalyst among all the catalysts.

CoOx was mainly in the form of nanosize Co3O4 which could stabilize the Au nanoparticles.

CoOx donated partial electrons to Au.

The interactions among Au, CoOx, and TiO2 account for the high catalytic activity for CO oxidation.