TY - JOUR
T1 - Visible-light-responsive graphitic carbon nitride
T2 - Rational design and photocatalytic applications for water treatment
AU - Zheng, Qinmin
AU - Durkin, David P.
AU - Elenewski, Justin E.
AU - Sun, Yingxue
AU - Banek, Nathan A.
AU - Hua, Likun
AU - Chen, Hanning
AU - Wagner, Michael J.
AU - Zhang, Wen
AU - Shuai, Danmeng
N1 - Funding Information:
We acknowledge the NSF Grant CBET-1437989, GW CEE and Chemistry Department start-up grants, GW Columbian College Facilitating Fund, and JHU Water SEED grant for supporting our study. Computational resources were provided under DOE contract DE-AC02-06CH11357 and NSF contract TG-CHE130008. We thank USNA, Elizabeth Eves and Dr. Julio A. N. T. Soares at UIUC, and Dr. Michael Jean-Claude Nalbandian at UCR for the support in materials characterization. We also thank John J. Hanchak at GWP and Michael R. Rumke at BRWRF for providing water samples.
Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/12/6
Y1 - 2016/12/6
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=85008946173&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85008946173&partnerID=8YFLogxK
U2 - 10.1021/acs.est.6b02579
DO - 10.1021/acs.est.6b02579
M3 - Article
C2 - 27934277
AN - SCOPUS:85008946173
SN - 0013-936X
VL - 50
SP - 12938
EP - 12948
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 23
ER -