N-doped porous carbons have shown great potential as CO₂ adsorbents. In the current work, we proposed the use of oxamic acid potassium salt (OAPS) as a novel and bifunctional activator for direct synthesis of N-doped porous carbon. OAPS served as both chemical activator and nitrogen source at the same time. N-doped carbons were prepared from different biomass materials including cellulose, agar, and glucose. The yielded carbons exhibited micropores dominated porous structure. Effects of activation conditions and biomass types on the carbons’ physicochemical properties were thoroughly studied. As a result, the carbons showed high specific surface area (733–2438 m²/g) and nitrogen content (1.51–3.92 wt%). The presence of narrow micropores and doped nitrogen qualified OAPS activated carbons as efficient CO₂ adsorbents. These carbons demonstrated high CO₂ uptake of 3.91 mmol/g at 25 °C and 1 bar. Respective effects of narrow micropores and N-doping on CO₂ adsorption were also analyzed and revealed. The current study indicated that OAPS could be used as a very convenient and versatile activator for the preparation of N-doped carbonaceous CO₂ adsorbents.

N掺杂的多孔碳已显示出作为CO ₂吸附剂的巨大潜力。在目前的工作中，我们提出使用草酸钾盐（OAPS）作为一种新型的双功能活化剂，用于直接合成 N 掺杂的多孔碳。OAPS 同时作为化学活化剂和氮源。N掺杂碳由不同的生物质材料制备，包括纤维素、琼脂和葡萄糖。所得碳表现出以微孔为主的多孔结构。深入研究了活化条件和生物质类型对碳理化性质的影响。结果，碳表现出高比表面积（733-2438 m ²/g）和氮含量（1.51-3.92 wt%）。窄微孔和掺杂氮的存在使 OAPS 活性炭成为有效的 CO ₂吸附剂。这些碳在 25 °C 和 1 bar 下表现出 3.91 mmol/g 的高 CO ₂吸收。还分析并揭示了窄微孔和N掺杂对CO _{2吸附的各自影响。}目前的研究表明，OAPS 可以作为一种非常方便和通用的活化剂用于制备 N 掺杂的碳质 CO ₂吸附剂。