Among the carbons carbonised and activated for six hours, the ordered domain sizes increased as the synthesis temperature increased, e.g. from 23.9 Å 2 to 49.2 Å 2 for HTC-600 and HTC-750, respectively. HTC-1000_1 exhibits similar behaviour to most commercial carbons, while HTC-1200_1 with an intermediate simulated ordered area of around 308 Å 2 shows the lowest capacitance among all studied carbons, due to limited porosity and ion adsorption capacity (Figure , Table ).