Abstract:
Porous carbon nanostructures have long been studied because of their importance in many natural
phenomena and their use in numerous applications. A more recent development is the ability to produce
porous carbon materials with tuneable properties for electrochemical applications, which has enabled
new research directions towards the production of suitable carbon materials for energy storage
applications. Thus, this work explores the activation of carbon from polyaniline (PANI) using a lesscorrosive
potassium carbonate (K2CO3) salt, with different mass ratios of PANI and the activating agent
(K2CO3 as compared to commonly used KOH). The obtained activated carbon exhibits a specific surface
area (SSA) of up to 1700 m2 g 1 for a carbon derived PANI : K2CO3 ratio of 1 : 6. Moreover, the
prepared samples were tested as electrode materials for supercapacitors with the results showing
excellent electrical double layer capacitor behavior. Charge storage was still excellent for scan rates of
up to 2000 mV s 1, and a capacitance retention of 70% at a very high specific current of 50 A g 1 was
observed. Furthermore, the fabricated device can deliver an energy density of 25 W h kg 1 at a specific
current of 0.625 A g 1 and a power density of 260 W kg 1 in 1-ethyl-3-methylimidazolium
bistrifluorosulfonylimide (EMIM-TFSI) ionic liquid, with excellent rate capability after cycling for 16 000
cycles at 3.0 V with 98% efficiency. These results are promising and demonstrate the electrode's
potential for energy storage, leading to the conclusion that K2CO3 is a very good alternative to corrosive
activation agents such as KOH in order to achieve high electrochemical performance.
