The synthesis of TiO2 using a nanocrystalline cellulose template improves its photocatalytic performance

Using cellulose nanocrystals (CNCs) as a template in the production of TiO 2 has a positive impact on its crystal and porous structure, ultimately improving its photocatalytic performance. In this study, TiO 2 photocatalysts with mesoporous anatase structures were prepared by acid-catalyzed hydrolysis using sulfate-ester-modified CNCs as the template. The effects of CNC concentration on the structure and performance of TiO 2 were investigated in detail. The addition of CNCs was found to inhibit TiO 2 transformation from the anatase to rutile phase, and abundant hydroxyl and sulfate ester groups on the CNCs provide narrow confined spaces for the crystal growth of TiO 2 , leading to the generation of smaller crystals with more exposed (001) crystal faces. Moreover, the CNCs act as a template for the pore structure remaining after calcination, thus increasing the specific surface area of the TiO 2 . Among the numerous samples evaluated, that prepared with a CNC concentration of 0.15 wt% and calcined at 600 °C had the highest percentage of (001) crystalline surface exposure. In photodegradation tests using phenol as a model pollutant, a degradation rate of 97.4 % and mineralization rate of 79.9 % were achieved with 60 min of light exposure. Thus, this study provides a clear approach for the directional synthesis of mesoporous TiO 2 from biomass template materials.