The development of new materials capable of fixing CO₂ into value-added products has become an exciting research field. Besides mitigating the rising level of CO₂, such materials also enable CO₂ as a C1 carbon source for useful industrial synthons. This article reports on the stepwise synthesis of a melamine functionalized silica-coated iron oxide (FSNM) material for selective CO₂ capture and its catalytic conversion into a useful product. The synthesis of FSNM has been achieved by covalently grafting the melamine group in the pores of mesoporous silica-coated Fe₃O₄ (Fe₃O₄@SiO₂) particle using isocyanate as a cross-linker. While the Fe₃O₄ core, owing to its superparamagnetic property, enables the easy retrieval of the material from the reaction mixture and, thus, enhances the recyclability, mesoporous silica coating offers a larger surface area for adsorption. The organic functionalities, containing melamine and carbamide moieties, facilitate the selective adsorption of CO₂ on the material with a maximum CO₂ uptake of 0.48 mmol/g at 1 bar and 298 K with excellent CO₂/N₂ selectivity. Moreover, the acid-base interactions between the acidic CO₂ and basic amine groups enable the FSNM to catalyze the cycloaddition of CO₂ with different epoxides to afford a series of cyclic carbonates, in the presence of tetrabutylammonium bromide (TBAB) as a co-catalyst, under facile and solvent-free conditions. These results strongly support that melamine functionalized Fe₃O₄@SiO₂ affords new aspects towards environmentally friendly and recoverable hybrid adsorbent for adsorption and fixation of CO₂ into the valuable products.

能够将CO ₂固定在增值产品中的新材料的开发已经成为令人兴奋的研究领域。除了减轻CO ₂的上升水平外，此类材料还使CO ₂成为有用的工业合成器的C1碳源。本文报道了逐步合成三聚氰胺功能化的二氧化硅涂层的氧化铁（FSNM）材料，用于选择性捕获CO ₂及其催化转化为有用的产品。FSNM的合成是通过将三聚氰胺基团共价接枝到介孔二氧化硅包覆的Fe ₃ O ₄（Fe ₃ O ₄ @SiO）的孔中而实现的₂）使用异氰酸酯作为交联剂的颗粒。Fe ₃ O ₄核由于具有超顺磁性，因此可以轻松地从反应混合物中回收材料，从而提高了可回收性，而介孔二氧化硅涂层则提供了更大的吸附表面积。包含三聚氰胺和尿素基团的有机官能团有助于在材料上以1 bar的最大CO ₂吸收量为0.48 mmol / g和298 K的情况下选择性吸附CO ₂，并且具有出色的CO ₂ / N ₂选择性。此外，酸性CO ₂和碱性胺基之间的酸碱相互作用使FSNM成为可能在四丁基溴化铵（TBAB）作为助催化剂的条件下，在方便且无溶剂的条件下，用不同的环氧化物催化CO ₂的环加成反应，得到一系列环状碳酸酯。这些结果有力地证明了三聚氰胺官能化的Fe ₃ O ₄ @SiO ₂为环保和可回收的混合吸附剂提供了新的方面，以将CO ₂吸附和固定在有价值的产品中。