Accumulation of localized charge on the surface of polymeric carbon nitride boosts the photocatalytic activity. (1st June 2022)

• Record Type: Journal Article
• Authors: Jiang, Yabin; Zeng, Lei; Cao, Chi; Yang, Wensheng; Huang, Limin
• Is Part Of: Journal of materials science & technology. Volume 111(2022)
• Page Start: 9
• Page End: 16
• Publication Date: 2022-06-01
• Subjects: g-C3N4 -- Charge separation -- Photocatalytic H2 evolution -- Directional migration; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2021.08.087
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: The in-planar directional charge transfer of polymeric C3 N4 can be realized by surface modification with ethylenediamine. The increased -NH2 groups induced the generation of midgap states and accumulation of electrons. The modified C3 N4 exhibits excellent photocatalytic activities for hydrogen evolution and MO degradation. Abstract: The random mobility of charge carriers is a main factor causing the low photocatalytic efficiency of g-C3 N4 . Thus, the controllable migration of charge carriers is a rational strategy to suppress the charge recombination and facilitate charge separation. Herein, an ethylenediamine modified g-C3 N4 displays improved photocatalytic activity. The excellent charge separation efficiency is confirmed to be a key factor for the enhancement. The TEM observation after photo-depositing Pt nanoparticles and DFT calculations verify the accumulation of electrons on some areas of g-C3 N4 surface. The increased -NH2 groups significantly tune the electronic structure of g-C3 N4 after the modification. The generation of midgap states also affects the charge separation. Our reports provide a simple method to manage the migration of charge carriers and enable electrons directional transfer, which suppresses the recombination and improves the photocatalytic activity.