Influence of Multiwalled Carbon Nanotubes as Additives in Biomass-Derived Carbons for Supercapacitor Applications

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

Autores

Natalia Rey Raap (Autor) Outra; Maria Enterria (Autor) Outra; José Inácio Martins (Autor) Outra; Manuel Fernando R. Pereira (Autor) FEUP; José Luís Figueiredo (Autor) Outra

Revista

Título: ACS Applied Materials & Interfaces

Vol. 11 Nº 6

Páginas: 6066-6077

ISSN: 1944-8244

Editora: American Chemical Society

Indexação

ISI Web of Knowledge - 4 Citações

Scopus - 34 Citações

Projetos Associados

AIProcMat@N2020 - Advanced Industrial Processes and Materials for a Sustainable North Region of Portugal2020

Outras Informações

ID Authenticus: P-00Q-7DY

DOI: 10.1021/acsami.8b19246

Abstract (EN): Glucose-derived carbon/carbon nanotube (CNT) hybrid materials were prepared by hydrothermal carbonization of glucose in the presence of CNTs and subsequent carbonization, physical activation, or chemical activation. The proportion of CNTs added during the hydrothermal polymerization of glucose was varied to ascertain the optimum dose to maximize the performance of the carbon hybrids in supercapacitor applications. Both the thermal treatment applied and the addition of CNTs lead to changes in the textural and chemical properties of the activated carbons. It was observed that samples bearing CNTs exhibit higher number of nucleation centers for glucose oligomers to polymerize, and consequently, the behavior of the hydrothermal carbon toward activation differs according to the activating agent employed. Moreover, the initial chemical speciation dominated by acidic groups shifts to more basic functionalities (quinones and carbonyl groups) with the addition of CNTs. The effect of the different physicochemical properties of the prepared carbons on their electrochemical behavior was evaluated. The addition of 2 wt % of CNTs and subsequent chemical activation leads to electrode materials yielding 206 F g(-1) and 78% of capacitance retention up to 0.8 V and 20 A g(-1) and high rate cyclability (97% after 5000 cycles). The outstanding performance is ascribed to the high surface area, narrow mesopores, and phenol/carbonyl surface functionalities, which enhance molecular diffusion, the amount of stored energy, and electronic transportation, respectively.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 12