title: Application of Engineered Si Nanoparticles in Light-Induced Advanced Oxidation Remediation of a Water-Borne Model Contaminant.
abstract: Surface-engineered amphiphilic polymer-coated silicon nanoparticles (SiNPs) were employed as photocatalysts to capture and degrade a model organic contaminant (methanol) in water. This study represents the first time SiNPs have been employed in the initiation of advanced oxidation processes that are commonly used to degrade organic constituents in industrial wastewaters. The quantum yield of photocatalytic methanol oxidation and the corresponding yield factor for the generation of active OH radicals are reported. The size and surface defect dependent photocatalytic activity of SiNPs was investigated. The yield factors (η) decreased with increasing particle size and reached impressive values that exceeded that of equivalent TiO2 nanoparticle systems by 3-4 times and are comparable to the robust UV/Cl2 and UV/H2O2 systems. The higher photocatalytic efficiency of SiNPs is attributed to the combined effects of quantum confinement, effective band gap, and surface states, among which surface states play a dominant role. SiNPs provide a potentially tunable, biologically inert, and robust nanoparticle system for photocatalytic oxidation of wastewater contaminants.
authors.affiliation: Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Iqbal
authors.affiliation: Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada.
authors.forename: Tapas K
authors.initials: TK
authors.lastname: Purkait
authors.affiliation: Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2E9, Canada.
authors.forename: Greg G
authors.initials: GG
authors.lastname: Goss
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada.
authors.forename: James R
authors.initials: JR
authors.lastname: Bolton
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta , Edmonton, Alberta T6G 1H9, Canada.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Gamal El-Din
authors.affiliation: Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada.
authors.forename: Jonathan G C
authors.initials: JG
authors.lastname: Veinot
keywords: Si nanoparticles (SiNPs); advanced oxidation processes (AOP); photocatalysis; quantum yield (QY); wastewater remediation