Hydrothermal synthesis of nano porous ZnO-polysaccharides composites Kanako Kimura and Natalia n. Sergeeva School of Design, The Leeds Institute of Textile and Colour (LITAC), University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK We have developed a facile hydrothermal method modifying structural and antioxidant properties of ZnO using thermally degradable polysaccharides such as chitosan (CS) and hyaluronic acid (HA). ZnO-CS and ZnO-HA composites were produced at different temperatures and ratios to assess the degree of CS/HA carbonisation and its effect on the properties of the produced materials. Through the preparation of the composites, the formation of pores within ZnO crystals was confirmed. Morphology, size and the presence of pores were confirmed by SEM analysis; based on the FIB-SEM analysis, the pore size varies between 7-76 nm and increases further after annealing (700 °C) to 8-137 nm. This data demonstrates that the formation of pores during the synthesis is due to polysaccharide degradation and carbonisation. Finally, the antioxidant properties of composites were determined by DPPH and TEAC assay. The antioxidant activity of all composites has increased due to the successful transfer of CS/HA’s antioxidant properties to ZnO upon functionalization. ZnO-CS composites synthesised at higher temperature showed 100 % even at low concentrations while bare ZnO showed only 20 %, which suggests undeniable benefits of the CS carbonisation. References 1. Marlinda, A. R.; Yusoff, N.; Pandikumar, A.; Huang, N. M.; Akbarzadeh, O.; Sagadevan, S.; Wahab, Y. A.; Johan, M. R. Tailoring Morphological Characteristics of Zinc Oxide Using a One-Step Hydrothermal Method for Photoelectrochemical Water Splitting Application. International Journal of Hydrogen Energy 2019 , 44 (33), 17535–17543. https://doi.org/10.1016/j. ijhydene.2019.05.109. 2. Baruah, S.; Dutta, J. Hydrothermal Growth of ZnO Nanostructures. Sci Technol Adv Mater 2009 , 10 (1), 013001. https://doi. org/10.1088/1468-6996/10/1/013001. 3. Edalati, K.; Shakiba, A.; Vahdati-Khaki, J.; Zebarjad, S. M. Low-Temperature Hydrothermal Synthesis of ZnO Nanorods: Effects of Zinc Salt Concentration, Various Solvents and Alkaline Mineralizers. Materials Research Bulletin 2016 , 74 , 374–379. https://doi.org/10.1016/j.materresbull.2015.11.001. 4. Yu, S.; Dong, X.; Zhao, P.; Luo, Z.; Sun, Z.; Yang, X.; Li, Q.; Wang, L.; Zhang, Y.; Zhou, H. Decoupled Temperature and Pressure Hydrothermal Synthesis of Carbon Sub-Micron Spheres from Cellulose. Nat Commun 2022 , 13 (1), 3616. https:// doi.org/10.1038/s41467-022-31352-x. 5. Yu, H.; Guo, Z.; Wang, S.; Fernando, G. S. N.; Channa, S.; Kazlauciunas, A.; Martin, D. P.; Krasnikov, S. A.; Kulak, A.; Boesch, C.; Sergeeva, N. N. Fabrication of Hybrid Materials from Titanium Dioxide and Natural Phenols for Efficient Radical Scavenging against Oxidative Stress. ACS Biomater. Sci. Eng. 2019 , 5 (6), 2778–2785. https://doi.org/10.1021/ acsbiomaterials.9b00535.
P87F
Made with FlippingBook Learn more on our blog