Challenges in calculating the bandgap of triazine-based carbon nitride structures

Stephan N. Steinmann, Sigismund T. A. G. Melissen, Tangui Le Bahers, Philippe Sautet

Research output: Contribution to journalArticlepeer-review

26 Scopus citations

Abstract

Graphitic carbon nitrides form a popular family of materials, particularly as photoharvesters in photocatalytic water splitting cells. Recently, relatively ordered g-C3N4 and g-C6N9H3 were characterized by X-ray diffraction and their ability to photogenerate excitons was subsequently estimated using density functional theory. In this study, the ability of triazine-based g-C3N4 and g-C6N9H3 to photogenerate excitons was studied using self-consistent GW computations followed by solving the Bethe–Salpeter Equation (BSE). In particular, monolayers, bilayers and 3D-periodic systems were characterized. The predicted optical band gaps are in the order of 1 eV higher than the experimentally measured ones, which is explained by a combination of shortcomings in the adopted model, small defects in the experimentally obtained structures and the particular nature of the experimental determination of the band gap.
Original languageEnglish (US)
Pages (from-to)5115-5122
Number of pages8
JournalJ. Mater. Chem. A
Volume5
Issue number10
DOIs
StatePublished - 2017
Externally publishedYes

Fingerprint

Dive into the research topics of 'Challenges in calculating the bandgap of triazine-based carbon nitride structures'. Together they form a unique fingerprint.

Cite this