Q2. What is the main reason for the use of ACs?
In particular, AC is used to assemble nearly all commercial supercapacitors owing to its high surface area, relatively low cost, good electronic conductivity, well-developed manufacturing technologies and easy production in large quantities.
Q3. What was the electrochemical characterization of the supercapacitors?
The electrochemical characterization was performed at room temperature using a computercontrolled potentiostat (Biologic VMP3 multichannel generator) and consisted of cyclic voltammetry experiments (CV), and galvanostatic charge/discharge (CD) cycling tests.
Q4. How can the micropore size distribution be tuned?
the micropore size distribution can be tuned by increasing the activation temperature and controlling the ratio hydrochar/potassium oxalate/melamine.
Q5. What is the main reason for the change in the focus on biomass?
growing concern about sustainability has shifted attention towards the use of biomass or biomass derivatives as carbon precursors.
Q6. How much weight loss is the potassium oxalate monohydrate?
The TGA curve of potassium oxalate monohydrate shows a first weight loss ataround 110 ºC, which corresponds to the loss of hydration water (K2C2O4.H2O → K2C2O4 + H2O, 10 % weight loss).
Q7. What is the ratio of integrated intensities of activated carbons?
The ratio of integrated intensities ID/IG, which is used to measure the degree of disorder in carbon materials, has a value of 1.44 and 1.45 for HCOxK-2.7-2 and HCOxK3.6-2 respectively.
Q8. When did the Egyptians use wood char for the manufacture of bronze?
The first recorded case dates back to 3750 BC, when the Egyptians and Sumerians used wood char for the reduction of copper, zinc and tin ores in the manufacture of bronze [1].
Q9. What is the optimum ratio of potassium bicarbonate and melamine?
In the first step, the hydrochar material was added to an aqueous dispersion containing potassium oxalate monohydrate (K2C2O4/hydrochar weight ratio = 2.7, 3.6 and 6) and melamine (C3H6N6/hydrochar weight ratio in the 0-2 range).
Q10. What is the percentage of N in the activation temperature?
As can be seen in Table S2, with the rise in the activation temperature, the percentage of N progressively decreases, with the N/C ratio decreasing from ~0.23 at 400 ºC to 0.01 at T ≥ 750 ºC.
Q11. What is the peaks attributable to K2C2O4?
This peak, which is attributable to diimides (-N=C=N-) and cyanides (C≡N) and is absent in gC3N4 [31-34], confirms the presence of poorly polymerized carbon nitride.