Low temperature synthesized ZnO/Al2O3 nano-composites for photocatalytic and antibacterial applications

Urbanization promoted the leaching of abiotic and biotic pollutants in freshwater ecosystem and created the demand for sustainable technologies to ensure a supply of fresh water in the future. As a type of sustainable technology, nanomaterials have been enlisted as a potential candidate. In the present study, a series of ZnO/Al2O3 nano-composites (ZANC) were synthesized with a cost-effective method, followed by their application as a photocatalyst and as an antibacterial agent. ZANC were characterized for crystallinity, particle size, surface morphology, chemical state and band gap. ZnO with 10% Al2O3 content, calcined at 400 degrees C (ZA-2A) was found to be the optimal photocatalyst for the photo-degradation of dye, cibacron red and the pesticide, triclopyr (TC). Additionally ZANC showed improved antibacterial activity against both gram positive (Staphylococcus aureus and Bacillus subtilis) and gram negative (Escherichia. coli and Pseudomonas aeruginosa) microbes. The enhanced antibacterial and photo-degradation properties of the ZANC could be seen as a synergistic effect of amorphous Al2O3 and ZnO. Based on the outcome, ZANC has shown its potential for a sustainable solution towards the removal of organic dyes, pesticides and microbes in contaminated water.