Photocatalytic Degradation of Methylene Blue Solution Using N-doped Titanium Dioxide Thin Film

Anhydrous ethanol 100 mL was measured and a certain amount of tetrabutyl titanate and acetylacetone were added to label as the base solution A, which was mixed evenly under the stirring of a magnetic stirrer. Anhydrous ethanol 50 mL was added with a certain amount of nitric acid and water, mixed evenly and labeled as base solution B. N-doped titanium dioxide films were mixed into liquid B with ammonia as the N source in a certain proportion. The reaction was stirred by a stirrer under the condition of chamber temperature, and the pH value of the basic solution A should be continuously controlled between 3 and 4, and the basic solution B should be slowly added to the basic solution A. After magnetically stirring the prepared sol for 10 min, slowly adding a certain amount of ammonia water, and then continuing to stir for 15 min, N-doped titanium dioxide sol was obtained. The molar ratio of control acetyl acetone, nitric acid, tetrabutyl titanate, water and anhydrous ethanol is = 1:1:5:25:150. The suitable degradation conditions of the films were studied, including calcination time of 50 min, calcination temperature of 450°C, coating layer number of 4, and molar ratio of ammonia water to tetrabutyl titanate of 1:25. The prepared N-doped titanium dioxide sol was plated on the pre-treated substrate by rotating method, dried under natural conditions, calcined in Muffle furnace, kept the furnace temperature at 5°C/min to 450°C, kept constant at 450°C for 50 min, and then cooled to room temperature naturally, and the coating was completed once, and the above coating was repeated four times. N-doped titanium dioxide films prepared were used for photocatalytic degradation of methylene blue.