Grant: Strategic Projects - Group

Polycyclic aromatic hydrocarbons (PAHs) consisting of several fused benzene rings are found as products of the incomplete combustion of hydrocarbons as well as in the flowback from hydraulic fracturing, a technique widely used in Canada. Concerns have risen about PAH-contaminated wastewaters as several studies have proven their toxicity and/or carcinogenicity to humans and wildlife. Yet, the expected increase in oil production in Canada assumes an equal increase in contaminated water. This reveals the urgent attention needed for the effective treatment of PAHs in wastewaters as the potential public health impact of these contaminants in the aquatic ecosystem is becoming a serious concern that needs to be addressed. Conventional ultraviolet (UV) light based photocatalysis has proved to be ineffectual in these turbid wastewater media due to limited penetration depth of UV light. As a consequence, there is a significant demand for the development of more efficient, cost-effective technologies to degrade pollutants such as PAHs. In this context, near-infrared (NIR) activation of the photocatalytic process is suggested as a more versatile method of photocatalysis mediated treatment of turbid wastewaters. The proposed project involves the collaborative effort between a Canadian team (INRS-EMT - F. Vetrone) and a French team (Université Pierre & Marie Curie, Laboratory of Surface Reactivity - G. Costentin, J. Blanchard, and S. Boujday (co-affiliated to NTU, Singapore, laboratory of T. Steele) / Université Paris Sud, Laboratory of Physical Chemistry - C. Colbeau-Justin) aiming for the synthesis of new and innovative photocatalytic nanocomposites combining lanthanide-based upconverting nanoparticles (UCNPs) with a ZnO photocatalyst. Herein, the UV emission upon NIR excitation of the UCNPs will trigger the photocatalytic activity of the ZnO resulting in pollutant breakdown. This novel and innovative approach will be superior to current methodologies, as the limited penetration of UV light will be overcome by NIR-mediated in-situ UV generation. We expect that it will lead to a more efficient and cost-effective system for wastewater treatment and will create significant impact in the water industry.