The adsorption of CO₂ over CaO-based adsorbents has been an effective way to capture CO₂ at high temperature, but the adsorption capacity was hampered and the cycle durability was poor. To address the said problems, this paper reported the effect of Mn doping on the structure, morphology and CO₂ adsorption performances of CaO-based adsorbents synthesized by a sol-gel method. The characterization results showed that the addition of Mn was helpful to form abundant micropores and mesopores in the doped CaO-based adsorbent, and Mn can effectively prevent the sintering and agglomeration of CaO particles. Moreover, electron transfer occurred on the modified CaO-based absorbents. These findings suggested that Mn species induced both structural and electronic promotion effect, resulting in smaller particle, higher dispersion and specific surface area of CaO-based adsorbents and formation of some electron-rich oxygen and Ca species, ultimately boosting CO₂ adsorption performance. Especially, with the molar ratio of Ca/Mn being 20, the adsorbent Ca/Mn-20 presented the best CO₂ uptake and excellent cycle stability (up to 10 cycles). In addition, it can be concluded that the adsorption process of CO₂ was more obedient to the pseudo-second-order kinetic model, indicating the adsorption process was dominated by chemical adsorption.

在CaO基吸附剂上吸附CO ₂是一种在高温下捕获CO ₂的有效方法，但吸附能力受阻且循环耐久性较差。为了解决上述问题，本文报道了Mn掺杂对结构、形貌和CO _{2 的影响。}溶胶-凝胶法合成的CaO基吸附剂的吸附性能。表征结果表明，Mn的加入有助于在掺杂CaO基吸附剂中形成丰富的微孔和介孔，Mn可以有效地防止CaO颗粒的烧结和团聚。此外，电子转移发生在改性 CaO 基吸收剂上。这些发现表明，Mn 物质同时诱导结构和电子促进作用，导致 CaO 基吸附剂的颗粒更小、分散性和比表面积更高，并形成一些富电子氧和 Ca 物质，最终提高 CO ₂吸附性能。特别是当Ca/Mn摩尔比为20时，吸附剂Ca/Mn-20表现出最佳的CO ₂吸收和出色的循环稳定性（最多 10 个循环）。此外，可以得出结论，CO ₂的吸附过程更服从准二级动力学模型，表明吸附过程以化学吸附为主。