Mechanisms of charge accumulation of the electrochemical system LaMnO3 / AC

In this work, the electrochemical behavior of LaMnO3 perovskite material and nanoporous carbon material in an aqueous solution of lithium sulfate are studied. The regularities of the expediency of the joint functioning of these materials as electrodes for a hybrid electrochemical capacitor are determined. It was found that the value of the specific capacity of the investigated electrochemical system of LaMnO3 / electrolyte / AC is 52 F/g during the discharge of the system to 1 V and the value of specific energy is 112.1 J /g at a discharge current of 1 mA.

Mechanisms of charge accumulation in electrochemical systems formed based on of nanoporous carbon and manganese oxide

In this work, the processes occurring in electrochemical systems based on nanoporous carbon material and manganese oxide in an aqueous solution of lithium sulfate are analyzed. Furthermore, it is shows the feasibility of these materials combination cycling as electrodes of a hybrid electrochemical capacitor. The combination of electrode materials with different mechanisms of charge accumulation was determined. Consequently, an increase in the accumulated energy by more than 25% by the formation of an electric double layer and the occurrence of redox reactions based on carbon and manganese oxide respectively. The laboratory sample of an aqueous electrolyte hybrid electrochemical capacitor was formed. Moreover, the laboratory sample is electrochemically stable at an operating voltage of 2 V.

Electrical properties of composites based on nanoporous carbon material

In this work, the morphological and electrical properties of the composite nanoporous carbon material/thermally expanded graphite or acetylene black have been investigated. Nanoporous carbon material was obtained from plant materials by its thermochemical activation based on potassium hydroxide. The dependence of the specific capacity of the nanoporous carbon/electrolyte electrochemical system on the applied potential was determined by the impedance spectroscopy method. Furthermore, the concentration of charge transfer and the density of states, as well as the flat-band potential of the system under research, were determined based on the Mott-Schottky model.

Electrochemical properties of nanoporous carbon materials obtained from raw materials of plant origin (hemp shives)

The paper reveals the results of electrochemical studies of activated nanoporous carbon material (NPC) as an electrode material for electrochemical capacitors (EC), the charge of which is accumulated in an electrical double layer (EDL). NPC material has been obtained from raw material of plant origin (hemp shives) by thermochemical activation using phosphoric acid. It has been established that there is an optimal ratio between the amount of acid and precursor based on plant biomass that is equal to 0.75:1. The specific surface area of ​​the obtained NPCwas ~ 2000 m2/g, and the maximum specific capacitance of EC models based on them was ~ 113 F/g. At the same time, the contribution of the EDL capacitance to the total capacitance is 60-80 %.

Features of Nanoporous Carbon Material Synthesis

Creation of innovative products and technological breakthrough – phrases most often used in relation to objects located in the nanoscale area. Carbon nanomaterials (CNMs) of various morphologies and structures, which include nanotubes, graphene, nanoporous carbon, are one of the most studied materials of the nanotechnology industry at present. This is due primarily to the fact that their physico-mechanical and physico-chemical characteristics have a direct effect on the final product. At the same time, for a number of applications, the best performance is achieved at the highest possible values of specific surface parameters and porosity. Methods and an experimental technology for producing micro- and mesoporous carbon material have been developed. Depending on the feedstock and technological synthesis modes, a nanoporous carbon material is obtained with a predominance of micro- or mesopores, with a BET specific surface area in the range of 2000–4000 m2/g. The technology includes carbonization of the starting materials and subsequent chemical activation. The obtained activated carbon material can be used as sorbents for gaseous media, both in purification systems and as gas batteries for safe storage and transportation systems, as well as for solving a number of environmental problems.