Highly porous, flexible and robust cellulose acetate/Au/ZnO as a hybrid photocatalyst

In this research, we aimed to study the photocatalytic behavior of metal-polymer nanocomposite materials. Au/ZnO nanoparticles were synthesized via co-precipitation and then incorporated into the cellulose acetate using a phase inversion process to fabricate nanocomposite polymers. Scanning/transmission electron micrographs showed semi-rod shape prismatic ZnO nanostructures with gold nanoparticles on the tip. Crystal structure and chemical state of Au/ZnO nanoparticles were analyzed using X-ray diffraction and X-ray spectroscopy, respectively. Electron microscopy observations showed that the synthesized cellulose acetate-0.5 wt% Au/ZnO nanocomposite had porosity of 82.5 vol% which was higher than the pure cellulose acetate with 76.8 vol% porosity. Wettability test showed that the synthesized nanocomposites had a water contact angle of 72 +/- 1 degrees which was higher than that of the pure cellulose acetate with a contact angle of 61 +/- 4 degrees, indicating the hydrophobicity of the pure cellulose acetate was improved by the presence of 0.5 wt% Au/ZnO nanoparticles. Finally, the photocatalytic activity of the synthesized nanocomposite was measured by 'Eosin Y' removal from the wastewater and it was seen that the cellulose acetate-0.5 wt% Au/ZnO nanocomposite degraded 20 ppm Eosin Y after 180 min, while no photocatalytic activity was seen for the pure cellulose acetate.