Hard-templating of carbon using porous SiO2 monoliths revisited - Quantitative impact of spatial confinement on the microstructure evolution
Hard-templating of carbon using porous SiO2 monoliths revisited - Quantitative impact of spatial confinement on the microstructure evolution
复制标题
使用多孔SIO2整体重新审视的碳硬化 - 空间限制对微观结构演化的定量影响
DOI：
10.1016/j.carbon.2017.12.044
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发表时间：
2018-04
期刊：
影响因子：
10.9
通讯作者：
Marc O. Loeh;Felix M Badaczewski;M. Lehr;R. Ellinghaus;S. Dobrotka;J. Metz;B. Smarsly
中科院分区：
文献类型：
--
作者：
Marc O. Loeh;Felix M Badaczewski;M. Lehr;R. Ellinghaus;S. Dobrotka;J. Metz;B. Smarsly
硬模板法制备多孔二氧化硅是合成多孔炭的主要方法之一，常用于分离吸附和储能应用。在原子尺度上具有高度的结构有序性，即碳微观结构的大小和无序性是理想的，这与碳的电学/热导率和耐腐蚀性等物理化学性质密切相关。通常情况下，碳微结构的演变首先被认为是由前体的化学性质和所采用的热处理所决定的。这项工作首次采用一种先进的非石墨炭广角X射线散射数据评估方法，定量研究了空间限制对整体式介孔-大孔二氧化硅纳米铸造过程中微结构发展的影响。通过扫描电子显微镜、压汞测孔仪和氮气物理吸附等手段对硬模板化过程进行了表征，结果表明碳前驱体完全位于模板剂的介孔内。对所得多孔炭的结构表征表明，在纳米铸造过程中，空间限制对石墨烯堆积的尺寸和无序性有很大的影响，证明空间限制是一个重要的合成参数，需要仔细考虑。
Hard-templating of porous SiO2is one of the major approaches for the synthesis of porous carbons, frequently utilized in separation/adsorption as well as in energy storage applications. A high degree of structural order on the atomic scale, i.e. size and the disorder of the carbon microstructure is desirable, which is closely related to physical and chemical properties such as the electrical/thermal conductivity and the corrosion resistance. Usually, the evolution of the carbon microstructure is known to be foremost dominated by the chemical nature of the precursor and the applied heat-treatment. This work for the first time quantitatively examines the influence of spatial confinement on the microstructural development experienced throughout the nanocasting process in monolithic meso-macroporous SiO2, by employing an advanced evaluation approach for wide-angle X-ray scattering data of non-graphitic carbons. The hard-templating process was characterized by SEM, mercury intrusion porosimetry and N2-physisorption, revealing that the carbon precursor is exclusively located within the mesopores of the templates. The structural characterization of the obtained porous carbons showed that the size and disorder of the graphene stacks is massively influenced by the spatial confinement during the nanocasting process, proving that spatial restrictions are an important synthesis parameter and need to be carefully considered.