Noble-Metal-Free MOF-74-Derived Nanocarbons: Insights on Metal Composition and Doping Effects on the Electrocatalytic Activity Toward Oxygen Reactions

• Tipo: Artigo em Revista Científica Internacional
• Data: 2019

Autores

Víctor K. Abdelkader-Fernández (Autor) Outra; Diana M. Fernandes (Autor) Outra; Salete S. Balula (Autor) Outra; Luís Cunha Silva (Autor) Outra; Manuel José Pérez-Mendoza (Autor) Outra; F. Javier López-Garzón (Autor) Outra; Manuel Fernando R. Pereira (Autor) FEUP; Cristina Freire (Autor) Outra

Revista

Título: ACS Applied Energy Materials

Vol. 2 Nº 3

Páginas: 1854-1867

Editora: American Chemical Society

Indexação

ISI Web of Knowledge - 51 Citações

Scopus - 58 Citações

Outras Informações

ID Authenticus: P-00Q-7SJ

DOI: 10.1021/acsaem.8b02010

Abstract (EN): The continuous and dramatic increase of global demand for energy resources makes it urgent to develop affordable nanostructured materials to act as efficient electrocatalysts (ECs) in the energy-related reactions. Metal-organic framework (MOF) template pyrolysis for the production of nanostructured carbon-based materials is a very promising methodology to produce carbon-based ECs. Herein, we report the preparation, characterization (XPS, CHNS analysis, ICP-OES, XRD, TEM, and SEM/EDS), and application as oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) ECs of a plethora of nanostructured carbon materials derived from RT-synthesized (RT, room temperature) MOF-74 with different metal compositions, Co, Ni and Co/Ni, and dopant heteroatoms, N-, S- and N/S-dual-doping. This has allowed the study of the aforementioned parameters' influence on the OER and ORR electrocatalytic activity in alkaline medium. Highly synergetic effects have been detected in two cases: (1) when N/S-dual-doped carbon is produced from a monometallic Co-MOF-74 template, N,S-Co@C, and (2) when an undoped carbon is derived from bimetallic Co/Ni-MOF-74, Co/Ni@C. These two samples achieve OER performances with eta(10) = 0.41 and 0.44 V, respectively, along with Tafel slopes of 101 and 93 mV dec(-1), being close to the state-of-art OER catalyst performance. In addition, ORR tests showed that the effect of heteroatom doping on ORE, activity is always positive, regardless of metal composition.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 27