Visible-light-responsive graphitic carbon nitride: Rational design and photocatalytic applications for water treatment
Document Type
Article
Publication Date
12-6-2016
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-C3N4 with improved surface area and charge separation. Density functional theory (DFT) simulations indicated that carbon-doped g-C3N4 showed 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, supramoleculebased g-C3N4 showed 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-C3N4 in 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-C3N4 samples. Moreover, g-C3N4 is 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-C3N4 for efficient, robust,and sustainable water treatment.
Identifier
85008946173 (Scopus)
Publication Title
Environmental Science and Technology
External Full Text Location
https://doi.org/10.1021/acs.est.6b02579
e-ISSN
15205851
ISSN
0013936X
PubMed ID
27934277
First Page
12938
Last Page
12948
Issue
23
Volume
50
Grant
1437989
Fund Ref
National Science Foundation
Recommended Citation
Zheng, Qinmin; Durkin, David P.; Elenewski, Justin E.; Sun, Yingxue; Banek, Nathan A.; Hua, Likun; Chen, Hanning; Wagner, Michael J.; Zhang, Wen; and Shuai, Danmeng, "Visible-light-responsive graphitic carbon nitride: Rational design and photocatalytic applications for water treatment" (2016). Faculty Publications. 10101.
https://digitalcommons.njit.edu/fac_pubs/10101
