Bio-friendly titania-grafted chitosan film with biomimetic surface structure for photocatalytic application

• Published in: Carbohydrate polymers 2020-02, Vol.230, p.115584-115584, Article 115584
• Main Authors: Tseng, I-Hsiang, Liu, Zhi-Cheng, Chang, Po-Ya
• Format: Article
• Language: English
• Subjects: Chitosan; CO2 photoreduction; Leaf; Titania; XPS
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2019.115584

•Titania nanoparticles were anchored on biomimetic chitosan film for photocatalytic reduction.•Leaf-patterned surface improved carbon dioxide adsorption and film hydrophobicity.•Optical property and titania distribution of chitosan films were tunable. A series of biomimetic chitosan (CS) films grafted with titanium dioxide (TiO2) were successfully prepared for photocatalytic reduction of carbon dioxide (CO2). The replication of the hierarchical structure of natural leaves to the surface of CS was conducted by nanocasting technique. The presence of amine and hydroxyl groups on CS matrix was able to anchor TiO2 nanoparticles. The addition of cross-linking agent, glutaraldehyde, improved the denseness of CS matrix but affected the distribution of TiO2. The existence of biomimetic structures on films enhanced the hydrophobicity, thermal stability and CO2 adsorption. Moreover, the surface patterns influenced the optical absorption edge of TiO2-grafted films. Under the illumination of UVA (8-Watt) light source, the TiO2-grafted CS films were able to convert CO2 into carbon monoxide and trace amounts of methanol. The biofriendly CS-supported photocatalysts exhibited the potential for sustainable CO2 reduction for cleaner production of chemical fuels.