Oxygen vacancy-enriched MoO3−x nanobelts for asymmetric supercapacitors with excellent room/low temperature performance
- 29 April 2019
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of Materials Chemistry A
- Vol. 7 (21), 13205-13214
- https://doi.org/10.1039/c9ta03471d
Abstract
Oxygen vacancy-enriched MoO3−x nanobelts with oxygen vacancies up to 20% (equal to MoO2.4) were synthesized and demonstrated fast reaction kinetics. An asymmetric supercapacitor was assembled with active carbon (AC) as the anode and the as-prepared MoO3−x nanobelts as the cathode. A new aqueous electrolyte of H2SO4/ethylene glycol (EG) was investigated and found to work appropriately at low temperatures, even at −25 °C. The MoO3−x nanobelts electrode possesses excellent specific capacitance, rate capacity (1230 F g−1 and 1220 F g−1 at 5 A g−1 and 50 A g−1, respectively) and cycle performance (100% after 38 000 cycles). Its energy and power densities reached 111 W h kg−1 and 803 W kg−1 or 50 W h kg−1 and 27 321 W kg−1 and maintained 80 W h kg−1 and 794 W kg−1 or 17 W h kg−1 and 23 565 W kg−1 at −25 °C. It is hypothesized that the coexistence of oxygen vacancies and low valence Mo ions enhanced both mass and charge transport kinetics and catalyzed the redox reactions.Keywords
Funding Information
- National Natural Science Foundation of China (U1401246)
This publication has 55 references indexed in Scilit:
- Graphene Oxide‐Dispersed Pristine CNTs Support for MnO2 Nanorods as High Performance Supercapacitor ElectrodesChemSusChem, 2013
- Enhanced Charge Carrier Mobility in Two‐Dimensional High Dielectric Molybdenum OxideAdvanced Materials, 2012
- Oxygen-deficient metal oxide nanostructures for photoelectrochemical water oxidation and other applicationsNanoscale, 2012
- Ordered mesoporous α-MoO3 with iso-oriented nanocrystalline walls for thin-film pseudocapacitorsNature Materials, 2010
- Carbon-based materials as supercapacitor electrodesChemical Society Reviews, 2009
- Comparative Study on MoO3 and HxMoO3 Nanobelts: Structure and Electric TransportChemistry of Materials, 2008
- Nanostructured materials for advanced energy conversion and storage devicesNature Materials, 2005
- Raman spectroscopy of molybdenum oxidesPhysical Chemistry Chemical Physics, 2002
- Studies of activated carbons used in double-layer capacitorsJournal of Power Sources, 1998
- Helical microtubules of graphitic carbonNature, 1991