Influence of the gas atmosphere during the synthesis of g-C3N4 for enhanced photocatalytic H2 production from water on Au/g-C3N4 composites

Jiménez-Calvo P, Marchal C, Cottineau T, Caps V, Keller V (2019)

Publication Type: Journal article

Publication year: 2019

Journal

Journal of Materials Chemistry A Royal Society of Chemistry

Book Volume: 7

Pages Range: 14849-14863

Journal Issue: 24

DOI: 10.1039/c9ta01734h

Abstract

The design of Au/g-C3N4 nanocomposites for enhanced H2 production from water under solar and visible light irradiation is presented by varying the g-C3N4 synthesis atmosphere (air, N2, H2, Ar and NH3). We showed for the first time that the synthesis of g-C3N4 in a pure NH3 atmosphere led to enhanced photocatalytic performances between 3 and 9 times higher than g-C3N4 prepared in other gas atmospheres. The resulting, novel 0.3 wt% Au/g-C3N4-NH3 photocatalyst produced up to 324 μmol h^-1 gcat^-1 and 26 μmol h^-1 gcat^-1 of H2 corresponding to internal quantum yields of 1.85 and 0.60% under solar and visible light irradiation respectively, with an unusually low amount of triethanolamine used as the sacrificial agent (1 vol%). This enhanced activity was correlated to the structural, optical, porosity, and surface properties of g-C3N4, and to the quality of the interface with Au NPs. From an in-depth structure-activity correlation study, we highlighted the combined effects of a higher surface area with larger contribution of mesoporous volume, higher crystallization degree of g-C3N4-NH3 and lower deformation of nanosheets. Additionally, the ratio between tri-s-triazine and s-triazine based C3N4 was determined and used for the first time to point out the effect of different continuous gas flow atmospheres during synthesis. Furthermore, the suitable surface chemistry of g-C3N4-NH3 allowed more homogeneous coverage with small Au NPs yielding more intimate contact and higher quality of the interface between Au NPs and the g-C3N4 support.

Authors with CRIS profile

Pablo Jiménez Calvo

Involved external institutions

Institut de Chimie et Procédés pour l'Energie l'Environnement et la Santé (ICPEES) / Institute of Chemistry and Processes for Energy, Environment and Health

France (FR)

How to cite

APA:

Jiménez-Calvo, P., Marchal, C., Cottineau, T., Caps, V., & Keller, V. (2019). Influence of the gas atmosphere during the synthesis of g-C3N4 for enhanced photocatalytic H2 production from water on Au/g-C3N4 composites. Journal of Materials Chemistry A, 7(24), 14849-14863. https://dx.doi.org/10.1039/c9ta01734h

MLA:

Jiménez-Calvo, Pablo, et al. "Influence of the gas atmosphere during the synthesis of g-C3N4 for enhanced photocatalytic H2 production from water on Au/g-C3N4 composites." Journal of Materials Chemistry A 7.24 (2019): 14849-14863.

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