Green and scalable synthesis of 3D porous carbons microstructures as electrode materials for high rate capability supercapacitors

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 less-corrosive 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.

Electrochemical performance of polypyrrole derived porous activated carbon-based symmetric supercapacitors in various electrolytes

The electrochemical performance of porous carbon prepared from the polymerization and carbonization of pyrrole is presented in this work.

A wafer-scale Bernal-stacked bilayer graphene film obtained on a dilute Cu (0.61 at% Ni) foil using atmospheric pressure chemical vapour deposition

A wafer-scale (scale of an entire foil) AB-stacked bilayer graphene film obtained on a dilute Cu(Ni) foil using AP-CVD.

Exploring the stability and electronic structure of beryllium and sulphur co-doped graphene: a first principles study

First principles density functional theory calculations have been performed to explore the stability, structural and electronic properties of Be and S co-doped graphene sheets.

Asymmetric supercapacitor based on an α-MoO3 cathode and porous activated carbon anode materials

Low cost porous carbon materials were produced from cheap polymer materials and graphene foam materials which were tested as a negative electrode material in an asymmetric cell configuration with α-MoO₃ as a positive electrode.

Investigation of different aqueous electrolytes on the electrochemical performance of activated carbon-based supercapacitors

Porous activated carbons was synthesized by an environmentally friendly technique, with an in-depth experimental study carried out to understand the electrochemical behaviour in different aqueous electrolytes (KOH, LiCl, and Na₂SO₄).