Mesoporous chitosan–SiO₂ nanoparticles (NPs) were successfully synthesized. The prepared nanoparticles were characterized using TEM, FTIR, XRD, TGA, EDX, and (CHN) elemental analysis. From TEM micrograph, chitosan–SiO₂ NPs were sphere-like, pretty uniformly distributed with coarse surface. The average size of chitosan–SiO₂ NPs was determined as 211 nm with DLS, which was confirmed by TEM. The mesoporous structure of chitosan–SiO₂ NPs was characterized with N₂ adsorption/desorption measurements. BET surface area was 621 m² g^–1 and the total pore volume was 0.71 m³ g^–1. CO₂ adsorption was evaluated by a volumetric method. Chitosan–SiO₂ NPs showed a maximum CO₂ adsorption capacity of 4.39 mmol g^–1 at 25 °C and a high selective separation capacity for CO₂ over N₂ (S_CO2/N2 = 15.46). The influence of amines on carbon dioxide adsorption was discussed. Stable CO₂ adsorption/desorption was confirmed after six cycles of experiments. Therefore, chitosan–SiO₂ NPs exhibit great potential for CO₂ capture.

中文翻译：

---

介孔壳聚糖-SiO ₂纳米颗粒：合成，表征和CO ₂吸附能力

介孔壳聚糖-SiO ₂纳米颗粒（NPs）已成功合成。使用TEM，FTIR，XRD，TGA，EDX和（CHN）元素分析对制备的纳米颗粒进行表征。从透射电镜观察，壳聚糖-SiO ₂纳米颗粒呈球形，分布均匀，表面粗糙。用DLS测定的壳聚糖-SiO ₂ NP的平均大小为211 nm，这已通过TEM证实。壳聚糖-SiO ₂ NPs的介孔结构通过N ₂吸附/解吸测量来表征。BET表面积为621 m ² g ^–1，总孔体积为0.71 m ³ g ^–1。一氧化碳₂通过体积法评价吸附。壳聚糖-SiO ₂ NPs在25°C下的最大CO ₂吸附容量为4.39 mmol g ^–1，在N ₂之上具有较高的CO ₂选择性分离能力（S _{CO2 / N2} = 15.46）。讨论了胺对二氧化碳吸附的影响。经过六个实验循环，确认了稳定的CO ₂吸附/解吸。因此，壳聚糖-SiO ₂ NPs具有捕获CO _2的巨大潜力。