<p>Nitrogen- and oxygen-doped high specific surfaces of activated carbon with an optimized pore system have been obtained by the method of calcination at 1000°C, using ZIF-8 as the precursor. The ZnCl₂ is as the activating agent, which is reduced to Zn⁰ by the carbon in the precursor. And the specific surface area of activated carbon can reach up to 2569 m²&#xa0;g⁻¹. This is comparable to the specific surface area of activated carbon produced with KOH as the activating agent. The N₂ isothermal adsorption–desorption at 77&#xa0;K indicates that the specific surface area of N-doped super-activated carbon increases a little to 2838 m²&#xa0;g⁻¹, when the urea has been incorporated into the precursor as extra an nitrogen source. Interaction&#xa0;between N- and O-doped carbon and K⁺ ions in KOH is illustrated by the corresponding density function theory (DFT), and the electron cloud between K and the carbon material is simulated. The electrochemical measurements were conducted in 6&#xa0;M KOH and 1&#xa0;M Na₂SO₄, which confirms that nitrogen and oxygen doping has a significant increase in specific capacitance. The super-activated carbon with an optimized pore system possesses excellent electrochemical performance, which shows good application prospects for energy storage.</p>