Mechanism Analysis of Indoor Formaldehyde Decomposition by Nano-Titanium Oxide

The effects of nano-titanium oxide dosage, sunlight exposure time, adsorption time on the formaldehyde removal efficiency were studied. The nano-titanium oxide was characterized by a scanning electron microscope and X-ray diffraction analysis. The catalysis mechanisms of nano-titanium oxide on formaldehyde removal efficiency were discussed. The results show that formaldehyde removal efficiency of nano-titanium oxide was 42.5% and 59.6% without and with sunlight; it was 7% and 22.6% higher than that of active carbon, respectively. Nano- TiO2 can directly react in the range of sun's ray wavelength to decompound formaldehyde. The results may be used to provide a useful basis for further applying nano-TiO2 to indoor air purification in the near future.