The deployment of large-scale direct air capture (DAC) technology relies on the development of energy-efficient and cost-effective CO₂ capture materials. The high desorption temperature of the current DAC adsorbents, especially the supported polyamines, is undesirable. In this work, the "mixed-polyamines" concept was adopted to prepare class 1 adsorbents by impregnating both tetraethylenepentamine (TEPA) and diethanolamine (DEA) into the mesoporous SBA-15. The synergy of TEPA and DEA influences the reaction mechanism between CO₂ and amines sites, resulting in higher amine efficiency and lower regeneration temperature. Moreover, CO₂ adsorption and desorption kinetics are enhanced by the introduction of hydroxyl groups from DEA. The desorption process of solid polyamines-loaded adsorbents fits well with the Avrami model under ultra-dilute CO₂ concentrations. SBA-15 loaded mixed polyamine with a weight ratio of TEPA to DEA equaling to 4 shows a maximum CO₂ adsorption amount of 1.93 mmol/g at 400 ppm CO₂ and 25 °C, a fast adsorption rate of 1.82 mmol/(g·h), and a desorption rate of 0.26 mmol/(g·min) at 80°C within the first 5 mins, which is believed to be a promising DAC adsorbent for practical application.

大规模直接空气捕集 (DAC) 技术的部署依赖于开发节能且具有成本效益的 CO ₂捕集材料。当前的 DAC 吸附剂，尤其是负载型多胺的高解吸温度是不受欢迎的。在这项工作中，采用“混合多胺”概念通过将四亚乙基五胺 (TEPA) 和二乙醇胺 (DEA) 浸渍到介孔 SBA-15 中来制备 1 类吸附剂。TEPA和DEA的协同作用影响了CO ₂与胺位点之间的反应机理，导致胺效率更高，再生温度更低。此外，CO ₂吸附和解吸动力学通过引入来自 DEA 的羟基而增强。_{在超稀 CO 2}浓度下，固体多胺负载吸附剂的解吸过程与 Avrami 模型非常吻合。TEPA与DEA的重量比为4的SBA-15负载混合多胺在400 ppm CO ₂和25 ℃下的最大CO ₂吸附量为1.93 mmol/g，快速吸附率为1.82 mmol/(g· h)，在80°C的前5分钟内解吸率为0.26 mmol/(g·min) ，这被认为是一种很有前途的DAC吸附剂在实际应用中的应用。