Mechanistic Insights in Acceptorless Dehydrogenation of N-Heterocycles Using Graphenes as Carbocatalysts

Mollar-Cuni, Andrés ; García-Aznar, Pablo ; Martín, Santiago (Universidad de Zaragoza) ; Sastre, German ; García, Hermenegildo ; Mata, Jose A.

Resumen: Catalytic dehydrogenation is a critical transformation in the chemical and energy sectors, particularly for reversible hydrogen storage systems. One of the most promising systems for hydrogen storage is the development of liquid organic hydrogen carriers (LOHCs), which have the potential capacity of storing and releasing hydrogen gas on demand. Catalytic direct dehydrogenation represents a greener, promising method to generate hydrogen in situ from these hydrogen-dense carriers. The catalytic activity of graphene materials as metal-free carbocatalysts in the acceptorless dehydrogenation of N-heterocycles has been explored. Herein, a detailed mechanistic investigation has been conducted through both experimental (stoichiometric and masking experiments) and DFT calculations on the reaction mechanism. The proposed mechanism identifies o-quinone groups as the active sites responsible for catalysis, involving the transformation of o-quinone groups into epoxide intermediates, which release molecular hydrogen and regenerate the o-quinone groups, completing the catalytic cycle. This work provides insight into the design of efficient metal-free catalysts for their use in LOHCs storage systems, paving the way for sustainable energy solutions.

Idioma: Inglés

DOI: 10.1021/acsami.5c11895

Año: 2025

Publicado en: ACS applied materials & interfaces 17, 51 (2025), 69234-69244
ISSN: 1944-8244

Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2021-126071OB-C21
Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2021-126071OB-C22
Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2022-141433OB-I00
Financiación: info:eu-repo/grantAgreement/ES/DGA/E31-23R

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Química Física (Dpto. Química Física)