Metallic 1T phase MoS2 nanosheets as supercapacitor electrode materials


Acerce M. , Voiry D., Chhowalla M.

NATURE NANOTECHNOLOGY, cilt.10, ss.313-318, 2015 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 10 Konu: 4
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1038/nnano.2015.40
  • Dergi Adı: NATURE NANOTECHNOLOGY
  • Sayfa Sayıları: ss.313-318

Özet

Efficient intercalation of ions in layered materials forms the basis of electrochemical energy storage devices such as batteries and capacitors(1-6). Recent research has focused on the exfoliation of layered materials and then restacking the two-dimensional exfoliated nanosheets to form electrodes with enhanced electrochemical response(7-11). Here, we show that chemically exfoliated nanosheets of MoS2 containing a high concentration of the metallic 1T phase can electrochemically intercalate ions such as H+, Na+ and K+ with extraordinary efficiency and achieve capacitance values ranging from similar to 400 to similar to 700 F cm(-3) in a variety of aqueous electrolytes. We also demonstrate that this material is suitable for high-voltage (3.5 V) operation in non-aqueous organic electrolytes, showing prime volumetric energy and power density values, coulombic efficiencies in excess of 95%, and stability over 5,000 cycles. As we show by X-ray diffraction analysis, these favourable electrochemical properties of 1T MoS2 layers are mainly a result of their hydrophilicity and high electrical conductivity, as well as the ability of the exfoliated layers to dynamically expand and intercalate the various ions.