Photocatalytic equipment with nitrogen-doped titanium dioxide for air cleaning and disinfecting

Nitrogen-doped TiO2 nanoparticle photocatalysts were synthesized by a sol‐gel procedure using tetra-n-butyl orthotitanate as a titanium precursor and urea as a nitrogen source. Systematic studies for the preparation parameters and their impact on the material’s structure were carried out by multiple techniques: thermogravimetric and differential scanning calorimetric analysis, x-ray diffraction, scanning electron microscope, transmission electron microscopy, energy dispersive x-ray spectroscopy and UV‐Vis diffuse reflectance spectrophotometry showed that the nitrogen-doped TiO2 calcined at 500 C for 3h exhibited a spherical form with a particle size about 15‐20nm and crystal phase presented a mixture of 89.12% anatase. The obtained product was deposited on a porous quartz tube (D = 74mm; l = 418mm) to manufacture an air photocatalytic cleaner as a prototype of the TIOKRAFT company’s equipment. The created air cleaner was able to remove 60% of 10ppm acetone within 390min and degrade 98.5% of bacteria (total aerobic bacteria and fungi, 300cfum 3 ) within 120min in a 10m 3 box. These photodegradation activities of N-TiO2 are higher than that of the commercial nano-TiO2 (Skyspring Inc., USA, particle size of 5‐10nm).