Gatti G, Costenaro D, Vittoni C, Paul G, Crocellà V, Mangano E, Brandani S, Bordiga S, Cossi M, Marchese L, Bisio C
Dipartimento di Scienze e Innovazione Tecnologica and "Centro interdisciplinare Nano-SiSTeMI", Università del Piemonte Orientale, via T. Michel 11, 15121 Alessandria, Italy.
Phys Chem Chem Phys. 2017 May 31;19(21):14114-14128. doi: 10.1039/c6cp08048k.
Hybrid organic-inorganic SBA-15 silicas functionalized with increasing amounts of amino groups were studied in this work aiming to evaluate the effects of their physico-chemical properties on CO capture ability. Three different amino-silane species were used: 3-aminopropyltriethoxysilane (APTS), 3-(2-aminoethyl)aminopropyltrimethoxysilane (EAPTS) and 3-[2-(2-aminoethyl)aminoethyl] aminopropyltrimethoxysilane (PAPTS). More specifically, samples were prepared by using two methods, following a post-synthesis grafting procedure and a one-pot preparation method. Experimental and computational techniques were used to study the structural and textural properties of the obtained samples and their surface species in relation to the adopted preparation method. For the most reactive samples, additional hints on the interactions of organosilane species with the silica surface were obtained by a combination of IR and SS-NMR spectroscopy, with particular emphasis on the effects of the silane chain length on the mobility of the organic species. Advanced complementary solid-state NMR techniques provided deeper information on the interactions of organosilane species with the silica surface. Finally, the amount of CO adsorbed was estimated by comparing the classical microcalorimetric analysis method with a new type of screening test, the Zero Length Column analysis, which is able to evaluate small amounts of samples in a very short time and the adsorption properties of the adsorbents. The reactivity of the amino-modified silica samples is deeply influenced by both the preparation route and by the type of organosilane used for the functionalization of the materials. In particular, samples prepared by the post-synthesis grafting procedure and containing higher amount of amino groups in the chain are more reactive, following the order PAPTS > EAPTS > APTS.
本研究对负载量不断增加的氨基官能化的有机-无机杂化SBA-15硅石进行了研究，旨在评估其物理化学性质对CO捕获能力的影响。使用了三种不同的氨基硅烷：3-氨丙基三乙氧基硅烷（APTS）、3-(2-氨乙基)氨丙基三甲氧基硅烷（EAPTS）和3-[2-(2-氨乙基)氨乙基]氨丙基三甲氧基硅烷（PAPTS）。具体而言，采用两种方法制备样品，即后合成接枝法和一锅法。运用实验和计算技术研究所得样品的结构和织构性质及其表面物种与所采用制备方法的关系。对于反应活性最高的样品，通过红外光谱和固体高分辨核磁共振光谱相结合的方法，获得了有关有机硅烷物种与二氧化硅表面相互作用的更多线索，特别强调了硅烷链长度对有机物种迁移率的影响。先进的互补固态核磁共振技术提供了有关有机硅烷物种与二氧化硅表面相互作用的更深入信息。最后，通过将经典的微量热分析方法与一种新型筛选测试——零长度柱分析进行比较来估算CO的吸附量，零长度柱分析能够在极短时间内评估少量样品以及吸附剂的吸附性能。氨基改性硅石样品的反应活性深受制备路线以及用于材料官能化的有机硅烷类型的影响。特别是，通过后合成接枝法制备且链中氨基含量较高的样品反应活性更高，顺序为PAPTS > EAPTS > APTS。
