Preparation And Catalytic Performance Of Noble Metal-doped Cu-based Composite Metal Oxides

In this paper, we report the synthesis of new type cu-based catalysts composite metal oxides which incorporates noble metal. Layered double hydroxides (LDHs) have many configuration merits, such as exchangeable layer elements, exchangeable anions within their interlayer and present an entire structure balanced in charge. Using the co-precipitation synthesis method, Cu/Zn/Al-LDHs were usefully prepared, and a further two steps ion-exchange intercalation step allows insertion of [M(EDTA)]n-(M=Pd, Ru, Rh) into Cu/Zn/Al-LDHs interlayer to prepared a highly active precursor composed of uniformly dispersed single phase crystal. The new type catalysts were obtained after decompounding the highly active precursor in adequate condition. The catalysts and their precursors were investigated by means of powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), simultaneous thermogravimetric and differential thermal analysis (TG-DTA), X-ray photoelectron spectroscopy (XPS) temperature programmed reduction (TPR) etc.Their catalytic performance has been studied, using catalytic oxidation reaction of phenol in H₂O₂ system as probe. The result indicated that Pd can improve the depth oxidation ability of the catalysts, while its ability to catalyze the above reaction can be increased with its calcinations temperature. It is found that not only Ru and Rh can improve the ability of catalyst, but also they can great enhance its depth oxidation ability. These observations are assigned to the interaction of Cu-M metallic particles and the high oxidation activity of the noble metal.