Zhao et al. reported a novel tobacco rods-derived carbon (TC) by hydrothermal carbonization, and KOH activation strategy for supercapacitor application . The TC showed a combination of hierarchical macro-, meso-, and micro-porous structure and exhibited the maximum SBET of 2115 m 2 g -1 . The XPS analysis of TC confirmed the N, and O elements with 1.1-1.4 wt%, and 6-10 wt%, respectively. The electrochemical measurements were performed using 6 M KOH aqueous solution. In a three-electrode configuration, TC delivered high capacitance of 286.6 F g -1 at 0.5 A g -1 current density along with a rate performance of 212.1 F g -1 at high current density of 30 A g -1 , and a cyclic stability with 96% capacitance retention after 10,000 cycles at 5 A g -1 . The fabricated TC supercapacitor devices delivered an energy density of 31.3 Wh Kg -1 at 0.5 A g -1 and power density of 11.9 kW Kg -1 at 15 A g -1 . Hu et al. reported the multi-heteroatom self-doped porous carbon synthesized through carbonization, and activation of amino acid-rich swim bladders and fabricated as highperformance supercapacitors . The pre-carbonized swim bladders (AC) were activated using KOH at different temperatures at 450, 550, 650, 750, and 850 ˚C in N2 atmosphere. The SBET of AC-550, AC-650, AC-750, and AC-850 were calculated from the N2 adsorption isotherms, which showed the values of 1591, 3047, 3068, and 3000 m 2 g -1 , respectively. The XPS studies showed N, O, and S heteroatom doping in the prepared carbon materials. The maximum amount of N doping with 9.01 at% was obtained for AC-450 with 0.33 at. % of S, while AC-550 showed 5.27 at% of N content, which was further decreased with increasing temperature (AC-650 (2.28 at%), AC-750 (1.67 at%), and AC-850 ˚C (0.81 at%)). The electrochemical performances of the carbon materials were carried out in 1 M H2SO4, and 1 M KOH electrolytes using a three-electrode system with nickel foam as current collector. In 1 M H2SO4, at the current density of 0.5 A g -1 , the specific capacitances of AC-450, AC-550, AC-650, AC-750, and AC-850 were 320, 419, 352, 312, and 239 F g -1 , while in 1 M KOH, the values were 326, 350, 330, 255, and 237 F g -1 , respectively. In both the electrolytes, AC-550 exhibited the maximum specific capacitance, and showed the cycling stability of 86 % after 10000 cycles, which is attributed to the high heteroatom doping and high SBET.