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Nanoscale electrocatalysis: visualizing oxygen reduction at pristine, kinked, and oxidized sites on individual carbon nanotubes.

ABSTRACT: There is a prevailing and widely adopted view that carbon nanotubes, which are finding considerable application in energy, healthcare, and electronics applications, are highly (electro)catalytically inert unless modified, doped, or defected. By visualizing the electrochemical reduction of oxygen (hydrogen peroxide generation) at high resolution along pristine (defect-free) regions of individual single-walled carbon nanotubes, we show that there is, in fact, significant activity comparable to that of standard gold electrocatalysts. Moreover, the activity is greatly enhanced at strained (kinked) sites and regions modified by oxidation. Single-walled carbon nanotubes are thus effective electrocatalysts in their own right and not just supports for other materials.

SUBMITTER: Byers JC

PROVIDER: S-EPMC4140457 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Nanoscale electrocatalysis: visualizing oxygen reduction at pristine, kinked, and oxidized sites on individual carbon nanotubes.

Byers Joshua C JC Güell Aleix G AG Unwin Patrick R PR

Journal of the American Chemical Society 20140804 32

There is a prevailing and widely adopted view that carbon nanotubes, which are finding considerable application in energy, healthcare, and electronics applications, are highly (electro)catalytically inert unless modified, doped, or defected. By visualizing the electrochemical reduction of oxygen (hydrogen peroxide generation) at high resolution along pristine (defect-free) regions of individual single-walled carbon nanotubes, we show that there is, in fact, significant activity comparable to tha ...[more]

PMID: 25061694

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