Sustainable periodically patterned carbon nanotube for environmental application: introducing the cheetah skin structure

Advanced Oxidation Processes (O3- and H2O2- assisted photocatalysis under Vis irradiation) were applied for the removal of recalcitrant pollutant from wastewater. The new periodically patterned carbon nanotube entitled cheetah skin structure introduced for the first time. The photocatalytic activity of cheetah skin CNT modified by poly (methyl methacrylate) (PMMA) and polyacrylonitrile (PAN) was tested in the decomposition of bisphenol A (BPA). The obtained CNT/PAN/PMMA composites differ in morphological structure. In PAN/CNT composite, a tubular coating was formed and a continuous coating layer of PAN on the surface of nanotubes was observed. In PAN/PMMA/CNT composite after carbonization process, the PMMA was completely evaporated and Carbon Nano Particles (CNP) with circular morphology in order of less than 10 nm were coated on the surface of nanotube walls forming a cheetah skin structure. The presence of CNP led to significant increase in degradation temperature. The application of tested nanocomposites enabled a significant removal of BPA. The highest changes in water pollution were observed during first 20 min of treatment. Nanocomposite containing 1.5% PAN - 0.5%PMMA demonstrated the best activity. During photo enhanced ozonation almost 90–95% of BPA was removed. H2O2slightly increased oxidation under Vis irradiation. The removal of BPA proceeded according to a pseudo-first order regime. Toxicity of BPA was significantly reduced after treatment and applied procedures enabled to obtain high quality non-toxic water. The obtained results clearly indicate that novel PAN-PMMA modified CNT could be a promising candidate for the photo mineralization of BPA.