The improvement of photocatalytic activity of monolayer g-C3N4via surface charge transfer doping. Issue 4 (9th January 2018)

• Record Type: Journal Article
• Authors: Yang, F. L.; Xia, F. F.; Hu, J.; Zheng, C. Z.; Sun, J. H.; Yi, H. B.
• Is Part Of: RSC advances. Volume 8:Issue 4(2018)
• Page Start: 1899
• Page End: 1904
• Publication Date: 2018-01-09
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7ra12444a
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : The improvement of optical adsorption for monolayer g-C3 N4 via surface charge transfer doping. Abstract : Graphite-like carbon nitride (g-C3 N4 ) has attracted much attention due to its peculiar photocatalytic performance as a visible-light-responsive photocatalyst. However, its insufficient sunlight absorption is not conducive to the photocatalytic activity of the g-C3 N4 . Herein, by using first-principles density functional theory (DFT) calculations, we demonstrated a simple yet efficient way to achieve improvement of photocatalytic activity of monolayer g-C3 N4 via surface charge transfer doping (SCTD) using the electron-drawing tetracyanoquinodimethane (TCNQ) and electron-donating tetrathiafulvalene (TTF) as surface dopants. Our calculations revealed that the electronic properties of monolayer g-C3 N4 can be affected by surface modification with TCNQ and TTF. These dopants are capable of drawing/donating electrons from/to monolayer g-C3 N4, leading to the accumulation of holes/electrons injected into the monolayer g-C3 N4 . Correspondingly, the Fermi levels of monolayer g-C3 N4 were shifted towards the valence/conduction band regions after surface modifications with TCNQ and TTF, along with the increase/decrease of work functions. Moreover, the optical property calculations demonstrated that the TCNQ and TTF modifications could significantly broaden the optical absorption of monolayer g-C3 N4 in the visible-light regions, yielding an improvement in the photocatalytic activity of monolayer g-C3 N4 . Our results unveil that SCTD is an effective way to tune the electronic and optical properties of monolayer g-C3 N4, thus improving its photocatalytic activity and broadening its applications in splitting water and degrading environmental pollutants under sunlight irradiation.