Multifunctional mixed valence N-doped CNT@MFe2O4 hybrid nanomaterials: from engineered one-pot coprecipitation to application in energy storage paper supercapacitors

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Clara Pereira (Author) FCUP; Costa, RS (Author) Other; Lopes, L (Author) Other; Bachiller Baeza, B (Author) Other; Rodriguez Ramos, I (Author) Other; Guerrero Ruiz, A (Author) Other; Tavares, PB (Author) Other; Cristina Freire (Author) FCUP; pereira, a. m. (Author) FCUP

Journal

Title: Nanoscale

Vol. 10

ISSN: 2040-3364

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 25 Citations

Scopus - 28 Citations

Other information

Authenticus ID: P-00P-1B3

DOI: 10.1039/c8nr03533d

Abstract (EN): This work reports on the design of novel mixed valence hybrid N-doped carbon nanotubes/metal ferrite nanomaterials (MFe2O4, M(ii) = Mn, Fe, Co) with tailored composition, and magnetic and electrical properties through a straightforward eco-sustainable and less time consuming one-pot in situ coprecipitation process. The potentialities of this strategy rely on the lack of oxidative treatments to the support and thermal annealing, besides the use of aqueous conditions, a chelating base (isopropanolamine) and low temperatures. The process afforded the controlled nucleation/growth of the MFe2O4 nanoparticles (NPs), with sizes of 3.2-5.4 nm and superparamagnetic properties, on the surface of the N-doped carbon nanotubes (CNT-N) and their immobilization by covalent bonding. The nitrogen-based functionalities of CNT-N allied with the use of a coprecipitation agent with coordinating properties towards M(ii)/Fe(iii) cations were responsible for these achievements. To unravel the potentialities of the novel nanohybrids (CNT-N@M), they were tested as electrode active nanomaterials in the fabrication of all-solid-state asymmetric paper supercapacitors (SCs). All asymmetric SCs presented significantly higher performance than the symmetric CNT-N based one, with an enhancement of the energy density to up to 6.0x and of the power density to up to 4.3x due to the occurrence of both non-faradaic and faradaic charge storage mechanisms. Moreover, they led to enhanced volumetric energy density (up to 11.1x) and power density (up to 5.2x) compared with other solid-state hybrid paper SCs based on carbon materials recently reported in the literature. These results highlight the importance of conjugating a conductive support bearing N-based functionalities with MFe2O4 NPs featuring redox properties towards synergistically enhanced energy storage.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 21