Adsorption and photocatalytic splitting of water on graphitic carbon nitride: a combined first principles and semiempirical study
- Graphitic carbon nitride, g-C3N4, is a promising organic photo-catalyst for a variety of redox reactions. In order to improve its efficiency in a systematic manner, however, a fundamental understanding of the microscopic interaction between catalyst, reactants and products is crucial. Here we present a systematic study of water adsorption on g-C3N4 by means of density functional theory and the density functional based tight-binding method as a prerequisite for understanding photocatalytic water splitting. We then analyze this prototypical redox reaction on the basis of a thermodynamic model providing an estimate of the overpotential for both water oxidation and H+ reduction. While the latter is found to occur readily upon irradiation with visible light, we derive a prohibitive overpotential of 1.56 eV for the water oxidation half reaction, comparing well with the experimental finding that in contrast to H-2 production O-2 evolution is only possible in the presence of oxidation cocatalysts.
Author details: | Jonas WirthGND, Rainer Neumann, Markus AntoniettiORCiDGND, Peter SaalfrankORCiDGND |
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DOI: | https://doi.org/10.1039/c4cp02021a |
ISSN: | 1463-9076 |
ISSN: | 1463-9084 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/24963918 |
Title of parent work (English): | Physical chemistry, chemical physics : a journal of European Chemical Societies |
Publisher: | Royal Society of Chemistry |
Place of publishing: | Cambridge |
Publication type: | Article |
Language: | English |
Year of first publication: | 2014 |
Publication year: | 2014 |
Release date: | 2017/03/27 |
Volume: | 16 |
Issue: | 30 |
Number of pages: | 10 |
First page: | 15917 |
Last Page: | 15926 |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
Peer review: | Referiert |