One Step Synthesis Of N-doped SO₄^2-/TiO₂ And Its Photocatalytic Activity

A low cost one-step synthesize approach for SO42-/N-doped-TiO2 using Ti(SO4)2 and NH4HCO3 as feedstocks was developed. Different synthesis conditions including calcinating temperature, calcinating shielding gas type, with or without ultrasonic cleaning and the concentration of H2SO4 were used when preparing the samples. TG,SEM,XRD,IR,XPS,UV-vis DRS and BET-BJH were adoped as characterization meanings. The adsorption property, UV and simulated sunlight photocatalytic activity on stphnic acid were evaluated. When the sample was synthesized under the condition of the concentration of H2SO40-0.2 M, without ultrasonic cleaning, being calcinated in atmosphere at 650℃, it achieved its best photocatalytic activity.In order to further improve the sample's photocatalytic activity, ultrasonic synthesis was used. The effect of power and the acting time of the ultrasonication on the property of the samples were evaluated. The results indicated that ultrasonic synthesis with a great power would improve the sample's dispersive property and photocatalytic activity, and prolonging the acting time a little bit would lead to a further photocatalytic activity improvement.MWCNTs were added to the sample. The photocatalytic activity of the sample was improved when the two of them were simply mixed by grinding them toghther. However, bonding those two with chemical bonds would cause a photocatalytic activity decrease, which was quite the opposite of our assumption. The cause of that was disgussed.