Synthesis of Vitamin B3 through a Heterogeneous Photocatalytic Approach Using Metal-Free Carbon Nitride-Based Catalysts

• Tipo: Artigo em Revista Científica Internacional
• Data: 2022

Autores

Raquel A. Fernandes (Autor) Outra; Maria José Sampaio (Autor) FEUP; Joaquim Luís Faria (Autor) FEUP; Cláudia G. Silva (Autor) FEUP

Revista

Título: Molecules

Vol. 11

Páginas: 1-1295

ISSN: 1420-3049

Editora: MDPI

Indexação

ISI Web of Knowledge - 0 Citações

Scopus - 0 Citações

Projetos Associados

LED-NETmix - LED-NETmix: um fotoreator inovador para a intensificação de processos em síntese química

Outras Informações

ID Authenticus: P-00W-6SP

DOI: 10.3390/molecules27041295

Abstract (EN): Vitamin B3 (nicotinic acid, VB3) was synthesized through the photocatalytic oxidation of 3-pyridinemethanol (3PM) under visible-light-emitting diode (LED) irradiation using metal-free graphitic carbon nitride (GCN) - based materials. A bulk (GCN) material was prepared by a simple thermal treatment using dicyandiamide as the precursor. A post-thermal treatment under static air and nitrogen flow was employed to obtain the GCN-T and GCN-T-N materials, respectively. The conditions adopted during the post-treatment revealed differences in the resulting materials' morphological, electronic, and optical properties. The post-treated photocatalysts revealed an enhanced efficiency in the oxidation of 3PM into VB3, with the GCN-T-N photocatalyst being the best-performing material. The defective surface, reduced crystallinity, and superior photoabsorption of GCN-T-N account for this material's improved performance in the production of VB3. Nevertheless, the presence of nitrogen vacancies in the carbon nitride structure and, consequently, the creation of mid-gap states also accounts to its highly oxidative ability. The immobilization of GCN-T-N in sodium alginate hydrogel was revealed as a promising strategy to produce VB3, avoiding the need for the photocatalyst separation step. Concerning the mechanism of synthesis of VB3 through the photocatalytic oxidation of 3PM, it was possible to identify the presence of 3-pyridinecarboxaldehyde (3PC) as the intermediary product.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 12