Porous intercalation compounds for aqueous supercapacitors based on lithium cobalt oxide

Currently the fast-growing interest in portable electronic devices and electric vehicles has stimulated extensive research in high performance energy storage devices, such as supercapacitors (SCs). They are a relatively new class of energy storage devices that can store a large amount of charge, and deliver it at high power rates.^1,2 However, their energy density is low (3-6 Whkg^-1).³ Therefore, one of the most investigated strategies to overcome the low energy density of supercapacitors is the use of conducting polymers and transition metal oxides as active masses.⁴

To date, intercalation compounds have attracted a lot of interest due to the development of lithium ion batteries.They have been typically used in organic electrolyte solutions, but aqueous examples are more interesting. More specifically, LiCoO₂ is a hexagonal layered structure belonging to Pnm space group .It is widely applied in lithium ion batteries due to its high capacity and stable structure during charging and discharging process. Due to the good reversibility of intercalation/deintercalation of Li⁺-ions it could be used as positive electrode for aqueous supercapacitors.⁵

The purpose of this research project is to obtain porous LiCoO₂ as cathode (negative mass) for supercapacitors. It will be prepared by template method and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction and Brunauer-Emmett-Teller surface area measurements. Electrochemical data will be obtained by cyclic voltammetry (CV), electrochemical impedance measurements (EIS) and charge-discharge measurements.

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