Tuning graphitic carbon nitride (g-C3N4) electrocatalysts for efficient oxygen evolution reaction (OER)

• Tipo: Artigo em Revista Científica Internacional
• Data: 2024

Autores

Torres-Pinto, A (Autor) FEUP; Díez, AM (Autor) Outra; Claudia G Silva (Autor) FEUP; Fariaa, JL (Autor) Outra; Sanromán, MA (Autor) Outra; Silva, Adrian (Autor) FEUP; Pazos, M (Autor) Outra

Revista

Título: Fuel

Vol. 360

ISSN: 0016-2361

Editora: Elsevier

Indexação

ISI Web of Knowledge - 0 Citações

Scopus - 0 Citações

Projetos Associados

SuN2Fuel - Produção foto-assistida de combustíveis verdes baseados em amoníaco

DRopH2O - Qualidade da água de consumo: alerta precoce e remoção de microcontaminantes por materiais inovadores à base de carbono

Outras Informações

ID Authenticus: P-00Z-HES

DOI: 10.1016/j.fuel.2023.130575

Abstract (EN): Nowadays, energy conversion and storage technologies are essential research topics due to the necessity of more sustainable processes. Specifically, water splitting is highly affected by slow kinetics and limited knowledge of the oxygen evolution reaction (OER). This work envisages the preparation of graphitic carbon nitride (g-C3N4) electrocatalysts for efficient OER by a facile one-pot method. The impact of the preparation temperature (450-650 degrees C) of g-C3N4 was assessed for the first time on water splitting processes and explained by different characterisation techniques. The unique crystal structure, surface chemistry, and electronic properties of the material prepared at 550 degrees C lead to a remarkable OER efficiency, with an overpotential of 355 mV at 10 mA cm -2 and a Tafel slope of 46.8 mV dec- 1. Interestingly, three major differences were observed when comparing the material prepared at 550 degrees C with those obtained at other temperatures: the reduced structural distortion, the superior composition in oxygen and the presence of terminal functional groups. Also, compared to other metal -free g-C3N4 electrocatalysts reported in the literature, we achieved lower Tafel slope values without additional post-treatments or co-catalysts. Hence, for the first time a metal-free catalyst defeats benchmark IrO2. The prepared electrodes were stable for up to 45 h, even when increasing the applied current density to 100 mA cm -2 for 15 h. Thus, this work provides a simple route for the fabrication of highly-efficient and long-lasting electrocatalysts for a remarkable OER performance.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 12