Rezumat
CZU 546.714-31+544.636/.638
The hydrothermal technique for the express-synthesis of a composite based on carbon nanotubes (CNTs) and manganese dioxide was proposed in this work. It is based on a direct reduction of potassium permanganate from water-iso-propanol media. The conditions of the synthesis (time, temperature, ratios between reagents) were optimized, and the primary and secondary processes that take place in the system were considered in detail. The synthesized CNT/MnO2-composite was studied by means of a wide range of physico-chemical and electrochemical methods to assess a possibility to use it as a positively charged electrode of an asymmetric supercapacitor (SC). The assembled SC-cell based on this composite and an activated carbon electrode keeps a sufficiently high specific power comparable with the traditional electrochemical double layer capacitors (0.82 kW/kg), while the energy density increased more than two-fold (12.14 W×h/kg).
Keywords: hydrothermal express-synthesis, CNT/ MnO2-composite, asymmetric supercapacitor.