Light-induced Remediation of Environmental Pollutants by Highly Adsorptive Activated Carbon Centered TiO2 Nanoflowers

Abstract

Absorbent materials such as activated carbon have been demonstrated to be very effective for the adsorption and removal of organic pollutants from the environment. However, this method of environmental remediation only allows the pollutant to be captured in the absorbent, instead of total decomposition into non-toxic end-products. This means that the absorbent material has to be disposed after one-time use, or additional steps has to be taken to clean the material before it can be reused. Motivated by this drawback, we have herein designed a hierarchical nanostructured composite material combining the adsorptive qualities of activated carbon with the photocatalytic activity of photoactive TiO2. However, contrary to existing literature, nano-sized activated carbon spheres are used instead of micron-sized spheres, and rather than TiO2 nanoparticles, thin and expansive 2D TiO2 nanosheets are synthesized. The combination of these 2 structures results in a flower-like 3D nanostructured monolithic composite material system capable of fast adsorption and complete degradation of environmental organic pollutants. The composite material was tested in the degradation of aqueous pollutants such as methyl orange dye and volatile organic compounds such as ethanol, methanol and formaldehyde. This synthesis effort highlights a highly effective material system that plays a pivotal role and holds great promise in commercial large scale cleaning operations.