Facile construction of cellulose nanocomposite aerogel containing TiO₂ nanoparticles with high content and small size and their applications

TiO₂/cellulose composite aerogels were easily fabricated by the in situ synthesis of TiO₂ nanoparticles in a cellulose matrix at a mild temperature (≤80 °C). The TiO₂/cellulose aerogel structure and morphology were analyzed with scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermal gravimetric analysis, and nitrogen adsorption–desorption tests as well as tensile testing. The results revealed that the TiO₂ content in the composite aerogels increased dramatically with an increase of the treating times in tetrabutyl titanate to achieve a value of 65 wt%, which was much higher than that in literatures. Depending on the number of hydrolysis cycles, the mean diameter of the TiO₂ nanoparticles was controlled to be approximately from 1.5 ± 1.0 to 3.5 ± 2.0 nm. The TiO₂/cellulose nanocomposite aerogel exhibited excellent mechanical strength, good UV screening ability as well as highly efficient photo-catalytic activity under weak UV light irradiation. This work opens a new avenue to construct TiO₂/cellulose aerogels with a high content and small size of TiO₂ nanoparticles, thus demonstrating potential applications in the fields of UV screening and catalyst.