Rachii B. Obtaining and physico-chemical properties of nanoporous carbon for electrochemical charge accumulation systems

The work is devoted to improve methods for obtaining nanoporous carbon material from natural raw materials with their predetermined physicochemical properties, developed surface area and controlled pore structure. The testing of these materials as the base component for electrode of electrochemical charge accumulation systems was realised. It is shown, that thermochemical activation of hydrothermal carbonized feedstock by potassium hydroxide provides a nanoporous carbon material with an average size of pores 1,7 - 2,2 nm, total volume of 0,8 cm3/g and high surface area of 1600 m2/g, where mesopores are 15% of the total pores. Optimized method of obtaining mesoporous carbon material shows that the surface area is 1500 m2/g, total pore volume is 1,3 cm3/g and mesopore size is 5 - 50 nm, which make up 75% of the total pores. The mechanisms of energy storage in electrochemical systems "nanoporous carbon/electrolyte" were modelled, where it was established the properties of these processes and defined the contribution of pore size in capacitance of electrochemical system. Depending on the used electrolyte and structural mor-phological characteristics of nanoporous carbon, it was obtained that the maximum values of electro-chemical system capacitance is 180 - 260 F/g in aqueous electrolytes and 60 - 100 F/g in organic ones. The adsorption activity was defined by the use of nanoporous carbon as sorbent in methylene blue 330 - 350 mg/g, methyl orange 340 - 360 mg/g and iodine 900 - 920 mg/g. The composite of carbon material and exfoliated graphite was proposed and approved as the elec-trode material for electrochemical capacitors. The laboratory standards of electrochemical capacitors were manufactured with electrodes which are based on obtained nanoporous carbon materials and studied their electrochemical properties.