Hence it was proposed that the presence of oxygen functionalities improve the wettability of the surface that augment the surface area, the porosity and the electrochemical performance of carbon materials. In another study, Liang et al. developed the oxygen enriched porous activated carbon by treating the carbonized form of camellia oleifera shell with KOH in the weight proportion of 1:3 to microwave irradiation involving the power of 600 W for 3 minutes (KMAC) and also the KOH/char of this biowaste was also subjected to thermal annealing at 800 °C under Ar environment about 3 h (KAC-800) . The electrochemical studies illustrated that KMAC electrode presented the gravimetric capacitance of 315 F g -1 at 0.5 A g - 1 in 2 M H2SO4 which is significantly greater compared to KAC-800 (202 F g -1 ). Likewise, the gravimetric capacitance of KMAC electrode obtained from the GCD curve at 0.5 A g -1 found to be 251 F g -1 in 6 M KOH solution and faintly higher than KAC-800 (214 F g -1 ). It was reported that the amount of oxygen present in KAC-800 from elemental investigation found to be 20.31 wt.% which is appreciably lesser compared to KMAC . Additionally, the level of carbonyl group in KMAC analysed from XPS technique found to be 26.49 at. % which is appreciably greater than KAC-800 . This work too illustrated that among the different types of oxygen such as quinone, phenolic and carboxylic acid, the quinone oxygen is involved in active participation with electrolyte ions via faradaically that could induce pseudocapacitance to the carbon materials which enhance the overall capacitance. On the other hand, the calculated SBET and pore volume correspond to KMAC found to be 1553 m 2 g -1 and 1.33 cm 3 g -1 which are superior to those of KAC-800 (1229 m 2 g -1 and 1.01 cm °C about 2 h under N2 atmosphere followed by ball milling for 20 minutes around 300 rpm and the activation with KHCO3 in three various weight ratios [860]. Among these, the FFC-4 submitted the highest gravimetric capacitance of 302.7 F g -1 at 0.5 A g -1 in 6 M KOH aqueous solution because it got the maximum SBET and total pore volume of 2147.9 m 2 g -1 and