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Electron Deficient Monomers that Optimize Nucleation and Enhance the Photocatalytic Redox Activity of Carbon Nitrides.

ABSTRACT: Polymeric carbon nitride (PCN) is usually synthesized from nitrogen-rich monomers such as cyanamide, melamine, and urea, but is rather disordered in many cases. Now, a new allotrope of carbon nitride with internal heterostructures was obtained by co-condensation of very electron poor monomers (for example, 5-amino-tetrazole and nucleobases) in the presence of mild molten salts (for example, NaCl/KCl) to mediate the polymerization kinetics and thus modulate the local structure, charge carrier properties, and most importantly the HOMO and LUMO levels. Results reveal that the as-prepared NaK-PHI-A material shows excellent photo-redox activities because of a nanometric hetero-structure which enhances visible light absorption and promotes charge separation in the different domains.

SUBMITTER: Zhang G

PROVIDER: S-EPMC6856808 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Electron Deficient Monomers that Optimize Nucleation and Enhance the Photocatalytic Redox Activity of Carbon Nitrides.

Zhang Guigang G Liu Minghui M Heil Tobias T Zafeiratos Spiros S Savateev Aleksandr A Antonietti Markus M Wang Xinchen X

Angewandte Chemie (International ed. in English) 20190909 42

Polymeric carbon nitride (PCN) is usually synthesized from nitrogen-rich monomers such as cyanamide, melamine, and urea, but is rather disordered in many cases. Now, a new allotrope of carbon nitride with internal heterostructures was obtained by co-condensation of very electron poor monomers (for example, 5-amino-tetrazole and nucleobases) in the presence of mild molten salts (for example, NaCl/KCl) to mediate the polymerization kinetics and thus modulate the local structure, charge carrier pro ...[more]

PMID: 31424624

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