Synthesis of nanosheet crystallites of ruthenate with an alpha-NaFeO2-related structure and its electrochemical supercapacitor property.

Collaborative Innovation Center for Nanotech Fiber, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan.
Inorganic Chemistry (Impact Factor: 4.59). 05/2010; 49(10):4391-3. DOI: 10.1021/ic100176d
Source: PubMed

ABSTRACT Unilamellar crystallites of conductive ruthenium oxide having a thickness of about 1 nm were obtained via elemental exfoliation of a protonic layered ruthenate, H(0.2)RuO(2).0.5H(2)O, with an alpha-NaFeO(2)-related crystal structure. The obtained RuO(2) nanosheets possessed a well-defined crystalline structure with a hexagonal symmetry, reflecting the crystal structure of the parent material. The restacked RuO(2) nanosheets exhibited a high pseudocapacitance of approximately 700 F g(-1) in an acidic electrolyte, which is almost double the value of the nonexfoliated layered protonated ruthenate.

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