Simple Route to Prepare Composite Nanocellulose Aerogels: A Case of Photocatalytic De-NO<sub><i>x</i></sub> Materials Application
Sergio Carrasco, Eduardo Espinosa, Z. González, Manuel Cruz‐Yusta, Luis Sánchez, Alejandro Rodríguez
Abstract
High Resolution Image Download MS PowerPoint Slide The preparation of nanocellulose/TiO 2 -based aerogels for the emission removal of nitrogen oxide (NO x ) species (De-NO x action) is proposed here. Using an innovative valorization strategy of agricultural waste valorization, the formulation of hybrid structures was successfully carried out following a simple colloidal route based on a heterocoagulation process between delignified cellulose nanofibers (CNFs) and TiO 2 nanoparticles (TiO 2 NPs). A facile freeze-drying process allowed shaping composite materials in which the nanocellulose aerogel acts as a 3D support for the photoactive phase. Under light irradiation, all samples showed a positive response to the NO abatement. The best selectivity was observed for the CNF100 sample (82%) which coupled the highest efficiency of 78% for NO removal, allowing us to achieve an outstanding NO x efficiency of 64%, values much higher than those for the TiO 2 P25 powder photocatalyst. Not only does the use of cellulose nanofibers as support for TiO 2 P25 provide good dispersion of the photocatalytic nanoparticles but also the specific cross-linked structure of the nanocellulose facilitates good contact and transfer of the reactive gas molecules, both increasing the photocatalytic activity.