Oxygen Vacancies for Better Supercapacitors

  • Author: ChemistryViews.org
  • Published: 04 November 2017
  • Copyright: Wiley-VCH Verlag GmbH & Co. KGaA
  • Source / Publisher: Chemical Communications/Royal Society of Chemistry (RSC)
  • Associated Societies: Royal Society of Chemistry (RSC), UK
thumbnail image: Oxygen Vacancies for Better Supercapacitors

Supercapacitors are an alternative to batteries. They charge and discharge very fast, but usually have much smaller capacities. Co3O4 nanosheets are a material with a high theoretical specific capacitance, which could improve the energy storage capacity of supercapacitors.

Xuefeng Guo, Nanjing University and Huanggang Normal University, both China, and colleagues have synthesized a range of two-dimensional Co3O4 nanosheets with different amounts of oxygen vacancies for use in supercapacitors. The team first prepared cobalt hydroxide precursors, which were calcined at 300 °C in air to give Co3O4 nanosheets. The nanosheets were then reduced to create oxygen vacancies, either in a mixture of hydrogen and nitrogen or in an NaBH4 solution. The resulting nanosheets have a thickness of about 20 nm and retain the overall structure of pristine Co3O4 nanosheets.

The researchers found an increasing number of oxygen vacancies from the pristine nanosheets, to the hydrogen-reduced ones, to the NaBH4-reduced material. The electrical conductivities and specific capacitances of the respective nanosheets increase in the same order. The oxygen-vacancy-rich NaBH4-reduced Co3O4 nanosheets have an excellent electrochemical performance, making them a promising material for supercapacitors.


Article Views: 1654

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission. more

Follow on Facebook Follow on Twitter Follow on YouTube Follow on LinkedIn Follow on Instagram RSS Sign up for newsletters

Magazine of Chemistry Europe (16 European Chemical Societies) published by Wiley-VCH