title: Visible-Light-Responsive Graphitic Carbon Nitride: Rational Design and Photocatalytic Applications for Water Treatment.
abstract: Graphitic carbon nitride (g-C3N4) has recently emerged as a promising visible-light-responsive polymeric photocatalyst; however, a molecular-level understanding of material properties and its application for water purification were underexplored. In this study, we rationally designed nonmetal doped, supramolecule-based g-C3N4with improved surface area and charge separation. Density functional theory (DFT) simulations indicated that carbon-doped g-C3N4showed a thermodynamically stable structure, promoted charge separation, and had suitable energy levels of conduction and valence bands for photocatalytic oxidation compared to phosphorus-doped g-C3N4. The optimized carbon-doped, supramolecule-based g-C3N4showed a reaction rate enhancement of 2.3-10.5-fold for the degradation of phenol and persistent organic micropollutants compared to that of conventional, melamine-based g-C3N4in a model buffer system under the irradiation of simulated visible sunlight. Carbon-doping but not phosphorus-doping improved reactivity for contaminant degradation in agreement with DFT simulation results. Selective contaminant degradation was observed on g-C3N4, likely due to differences in reactive oxygen species production and/or contaminant-photocatalyst interfacial interactions on different g-C3N4samples. Moreover, g-C3N4is a robust photocatalyst for contaminant degradation in raw natural water and (partially) treated water and wastewater. In summary, DFT simulations are a viable tool to predict photocatalyst properties and oxidation performance for contaminant removal, and they guide the rational design, fabrication, and implementation of visible-light-responsive g-C3N4for efficient, robust, and sustainable water treatment.
authors.affiliation: Department of Civil and Environmental Engineering, The George Washington University , Washington, DC 20052, United States.
authors.forename: Qinmin
authors.initials: Q
authors.lastname: Zheng
authors.affiliation: Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States.
authors.forename: David P
authors.initials: DP
authors.lastname: Durkin
authors.affiliation: Department of Chemistry, The George Washington University , Washington, DC 20052, United States.
authors.forename: Justin E
authors.initials: JE
authors.lastname: Elenewski
authors.affiliation: Department of Civil and Environmental Engineering, The George Washington University , Washington, DC 20052, United States.|Department of Environmental Science and Engineering, Beijing Technology and Business University , Beijing 100048, China.
authors.forename: Yingxue
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Chemistry, The George Washington University , Washington, DC 20052, United States.
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Banek
authors.affiliation: Department of Civil and Environmental Engineering, New Jersey Institute of Technology , Newark, New Jersey 07102, United States.
authors.forename: Likun
authors.initials: L
authors.lastname: Hua
authors.affiliation: Department of Chemistry, The George Washington University , Washington, DC 20052, United States.
authors.forename: Hanning
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Chemistry, The George Washington University , Washington, DC 20052, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wagner
authors.affiliation: Department of Civil and Environmental Engineering, New Jersey Institute of Technology , Newark, New Jersey 07102, United States.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Civil and Environmental Engineering, The George Washington University , Washington, DC 20052, United States.
authors.forename: Danmeng
authors.initials: D
authors.lastname: Shuai
mesh_terms: D002384:Catalysis; D006108:Graphite / Q000737:chemistry*; D008027:Light; D010636:Phenols; D018508:Water Purification
chemical_list: D010636:Phenols; D006108:Graphite