Preparation And Analysis Of Cobalt And Titanium Mixed Oxides Heterojunction For Photocatalytic Degradation Properties

In this study, cobalt and titanium mixed oxides were synthetized by altering the ratio of cobalt and titanium and calcination temperature with one-step facile hydrothermol method. This method is simple, facile and environment-friendly. The structure, morphology and pore strcture of cobalt and titanium mixed oxides heterojunction was analysised by X-ray diffraction, SEM, EDS, TEM, HRTEM, XPS and nitrogen adsorption-desorption isotherm measurement. The results showed that the cobalt and titanium mixed oxides heterojunction had high crystallinity, uniformity and the largest specific surface when the molar ratio of cobalt and titanium is 2:3 and the calcinated temperature is 400℃. We combined Co3O4 who possessed the properties of larger specific surface and visible light absorption with TiO2. The UV-vis diffuse reflection spectrum showed the cobalt and titanium mixed oxides heterojunction had the intense adsorption, this indicated that the cobalt and titanium mixed oxides heterojunction could adsorb visible light effectively.The photocatalytic activity of cobalt and titanium mixed oxides heterojunction was tested by degradation of the methylene blue (MB) under the visible light irradiation. The results indicated that all the cobalt and titanium mixed oxides heterojunction had the photocatalysis property, but the prepared condition of the best sample is the molar ratio of cobalt and titanium is 2:3 and the calcinated temperature is 400℃. The degradition efficiency of this sample was 65%.According to the difference of energy band structure for heterojunction, heterojunction could be divided into three types. The prepared best sample belong to the heterojunction of Ⅱ type based the energy band structure of TiO2 and Co3O4. Heterojunction of Ⅱ type has favorable mechanism of degradation pollutant, so photocatalytic activity of cobalt and titanium mixed oxides heterojunction is resonable.