Synthesis and structure determination of potassium copper selenide nanowires and solid-state supercapacitor application

• The new ternary alkali metal copper chalcogenide KCu4Se8 nanowires with average length of 30 mu m are synthesized using a modified composite-hydroxide mediated (M-CHM) approach. The prepared KCu4Se8 is characterized by XRD, EDS, FESEM and TEM analysis. The structure is determined by the newly developed Rotation Electron Diffraction technique. It is identified to be a body center tetragonal phase. The prepared KCu4Se8 is used to fabricate solid-state supercapacitors in which the thin film of the electrodes are made with pressure of 0 MPa, 5 MPa and 10 MPa, and their electrochemical properties are tested. It is found that 0 MPa supercapacitor displays best electrochemical performance and the specific capacitance of 25.3 F g(-1) is obtained at the scan rate of 5 mV s(-1). It also shows good long-term cycle property by recording 5000 cycles of galvanostatic charge/discharge operation. The specific capacitance can be enhanced to 93.7 F g(-1) at the scan rate of 5 mV s(-1) by coating 0.1 mg V2O5 nanowire on 0 MPa KCu4Se8 electrode.

Subject headings

NATURVETENSKAP  -- Kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences (hsv//eng)

Keyword

Potassium copper selenide

Nanowire

Supercapacitor

Vanadium pentoxide

Publication and Content Type

ref (subject category)

art (subject category)