KCu7S4 nanowires and the Mn/KCu7S4 nanostructure for solid-state supercapacitors

Abstract

We report a novel pseudocapacitor based on KCu 7 S 4 nanowires. To improve the electrochemical performance of the KCu 7 S 4 capacitor, we changed the structure of the KCu 7 S 4 nanowire electrode by coating Mn particles (Mn/KCu 7 S 4 ). The preferable capacitance is shown by the Mn/KCu 7 S 4 hybrid capacitor, which displays large specific capacitance (1620 F g À1 ) at a scan rate of 1 mV s À1 , high energy density, good cyclic stability and three supercapacitor units in series light 400 light-emitting diodes (LEDs) for 2 min. The much-increased capacity, rate capability, and cycling stability may be attributed to the Mn/KCu 7 S 4 hybrid structure, which enhances ionic and electronic transport through the electrode system.

Waxberry-Like Nanosphere Li4Mn5O12 as High Performance Electrode Materials for Supercapacitors

“…Firstly, the prepared Li 4 Mn 5 O 12 powder (both nanosphere and raspberry-like nanosphere Li 4 Mn 5 O 12 ) was mixed with carbon black and polytetra-fluorene-ethylene (PTFE) binder with a mass ratio at 80:15:5 in 5 mL of ethanol. The mixed slurry was directly painted onto a carbon cloth (6 cm × 2 cm) and dried in the vacuum at 60 • C for 24 h to remove the ethanol on the electrode [4,19,20]. Secondly, the carbon cloth was then cut into three parts (2 cm × 2 cm each) after drying.…”

Freestanding CNT–WO3hybrid electrodes for flexible asymmetric supercapacitors

“…1 SCs can be classied into two different kinds according to their charge storage mechanisms: electrical double-layer capacitors (EDLCs) and pseudocapacitors. [5][6][7][8][9][10][11][12][13][14] CNTs, owing to their outstanding conductive ability and good capacitive performance, have been studied for a long time and applied in various elds involving exible electronic and energy storage. [2][3][4] Pseudocapacitors, however, based on a fast redox reaction, commonly consisting of diverse transition metal oxides such as ruthenium oxide (RuO 2 ), manganese oxide (MnO 2 ) and tungsten oxide (WO 3 ) or conducting polymers like polypyrrole (PPy) and polyaniline (PANI), exhibit higher specic capacitance.…”

C@KCu7S4 microstructure for solid-state supercapacitors

“…In particular, the Mn/KCu 7 S 4 hybrid supercapacitor has been reported and displayed a good electrochemical performance with a large specic capacitance of 1620 F g À1 at a scan rate of 1 mV s À1 . 16 The KCu 7 S 4 consists of compound crystal lattice structure, and one of which forms quasi-one-dimensional channels and the K + ions occupy the channels. 16 Because of its double larger channel structure, it not only enhances the ionic and electronic transport, but also shortens the ionic diffusion path.…”

“…16 The KCu 7 S 4 consists of compound crystal lattice structure, and one of which forms quasi-one-dimensional channels and the K + ions occupy the channels. 16 Because of its double larger channel structure, it not only enhances the ionic and electronic transport, but also shortens the ionic diffusion path. When a bias is applied across the electrodes, the K + ions can well exchange with Li + ions.…”

“…When a bias is applied across the electrodes, the K + ions can well exchange with Li + ions. 16 So the KCu 7 S 4 microwires exhibit excellent electrochemical properties.…”