Abstract: A series of Ti-Zr-V-O catalytic composite materials were prepared by sol-gel method. Effect of doping zirconium on catalytic NO_x activities of Ti-V-O composite catalysts was investigated, and effects of doping zirconium on crystal form, crystalline morphology, chemical composition, functional group structure and specific surface area of titanium-vanadium composite oxides were characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy spectrum analysis (EDS), Fourier infrared spectrum (FT-IR) and N₂ physical adsorption (BET method) respectively. The experimental results show that doping zirconium can inhibit anatase crystalline transformation, refine grain size, change the crystalline morphology and enhance the solid acidity of Ti-V-O composite catalysts. Consequently, the catalytic properties of Ti-Zr-V-O composite catalysts are improved. In the process of selective catalytic reduction of NO over Ti-Zr-V-O/ATS ceramics monolithic catalysts, using NH₃ as reducing agent, doping zirconium widens the catalytic active zone to high temperature area about 100℃, and the highest NO conversion at 300℃ is increased by 17.3%.

Key words: Ti-Zr-V-O catalytic composite materials, sol-gel, doping zirconium, deNO_x