Flexible chain & rigid skeleton complementation polycarbazole microporous system for gas storage
Flexible chain & rigid skeleton complementation polycarbazole microporous system for gas storage
复制标题
柔性链条
DOI：
10.1016/j.micromeso.2019.03.042
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发表时间：
2019-08-01
影响因子：
5.2
通讯作者：
Liu, Xinwei
中科院分区：
文献类型：
--
作者：
Qiao, Shanlin;Li, Zheng;Liu, Xinwei
设计合成了五种柔性链与刚性骨架互补的聚咔唑网络P-Fo、PBT-C1（C2、C4、C6）用于储气。随着烷基长度从裸露到-CH3到-n-C6H12的增加，形貌（SEM）和热稳定性（TGA）发生了巨大的变化。 PBT-C1 的 Brunauer-Emmett-Teller (BET) 比表面积为 685 m(2) g(-1)，比没有 TTF 取代的网络 P-Fo 更大。然而，进一步用更长的烷基链（PBT-C2、C4、C6）取代烷基取代的TTF基序将使BET表面积急剧下降至小于100 m(2) g(-1)，随着侧链的变化，H-2、CO2和CH4吸附也发现了类似的趋势。值得一提的是，修饰烷基后，在零负载量下，CH4吸附焓可显着提高至52.1 kJ mol(-1) (PBT-C4)，表明烷基链段可以促进微孔与CH4分子之间的吸附势，而对H-2和CO2分子则无作用。这些结果表明，合理的柔性链接枝到刚性骨架上一方面可以堵塞微孔，但它也对BET比表面积、孔体积和气体吸附能力更加有利，特别是对甲烷的吸附能力。
Five flexible chain & rigid skeleton complementation polycarbazole networks P-Fo, PBT-C1 (C2, C4, C6) were designed and synthesized for gas storage. Increasing the length of alkyl groups from naked to -CH3 to -n-C6H12, the morphology (SEM) and thermostability (TGA) got tremendous changes. PBT-C1 exhibited Brunauer-Emmett-Teller (BET) specific surface area of 685 m(2) g(-1), which is larger than network P-Fo without TTF substitutions. Nevertheless, further replacing the alkyl-substituted TTF motifs with longer alkyl chains (PBT-C2, C4, C6) would bring a dramatic drop of BET surface areas to less than 100 m(2) g(-1), similar trends have found for H-2, CO2, and CH4 adsorption as side chains changed. It need to be mention that decorating the alkyl group, CH4 adsorption enthalpy can be significantly improved to 52.1 kJ mol(-1) (PBT-C4) at zero loading, indicating that alkyl segment can promote the adsorption potential between microporous and CH4 molecule, while have futile effect on H-2 and CO2 molecule. These results demonstrated that rational flexible chain grafted into the rigid skeleton at one hand can block the microporous, but it will also have more beneficial on the BET surface areas, pore volume and gas adsorption ability, especially for methane.