Abstract In this work, barley derived N, S-codoped porous carbons are synthesized through a simple, one-step chemical activation method using copper citrate as an activating agent. The copyrolysis of barley and copper citrate contributes to the formation of numerous micro-/mesopores and high surface area. Owing to redox reactions between copper citrate and carbon matrix during the activation process, the as-prepared porous carbon possesses a ultrahigh specific surface area of 2139.6 m2 g−1, hierarchical porous architecture with a large pore volume of 1.16 cm3 g−1, and high nitrogen, oxygen and sulfur contents. The resultant carbon material with high porosity and appropriate heteroatom doping exhibits a high specific capacitance of 401.6F g−1 at 0.5 A g−1 in a 6.0 M KOH electrolyte and good rate capability with the capacitance remaining 165.6F g−1 at 100 A g−1. Additionally, the assembled symmetric carbon-based supercapacitor delivers a high energy density of 30.9 Wh kg−1 and superior long-term cycling stability of 94.8% capacitance retention after 20,000 cycles in 1.0 M Na2SO4 electrolyte. This work provides a facile strategy to design high-surface-area porous carbons with adjustable pore structure and rich heteroatom amount, which holds a promising future for constructing high energy carbon-based supercapacitors.

中文翻译：

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一种制备大麦高表面积 N、S 共掺杂多孔碳的新策略，用于超级电容器

摘要 在这项工作中，使用柠檬酸铜作为活化剂，通过简单的一步化学活化方法合成了大麦衍生的 N, S 共掺杂多孔碳。大麦和柠檬酸铜的复制有助于形成大量微孔/中孔和高表面积。由于活化过程中柠檬酸铜与碳基体之间的氧化还原反应，所制备的多孔碳具有2139.6 m2 g-1的超高比表面积，具有1.16 cm3 g-1大孔体积的分级多孔结构，以及氮、氧和硫含量高。所得具有高孔隙率和适当杂原子掺杂的碳材料在 6.0 M KOH 电解质中在 0.5 A g-1 时表现出 401.6F g-1 的高比电容和良好的倍率性能，电容保持为 165。6F g-1 在 100 A g-1。此外，组装的对称碳基超级电容器可提供 30.9 Wh kg-1 的高能量密度和优异的长期循环稳定性，在 1.0 M Na2SO4 电解质中循环 20,000 次后电容保持率为 94.8%。这项工作为设计具有可调孔结构和丰富杂原子数量的高表面积多孔碳提供了一种简便的策略，为构建高能碳基超级电容器提供了广阔的前景。