Wu Jie, Zhang Hui, Feng Yan, Zhang Xiao, Yao Tongjie, Lian Yongfu
Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University, Harbin, 150080, P.R. China.
MIIT Key Lab of Critical Materials Technology, for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150090, P.R. China.
Chemistry. 2017 Dec 1;23(67):17095-17102. doi: 10.1002/chem.201703514. Epub 2017 Nov 8.
Compared with integrated capsules, ruptured ones have better mass diffusion and transport properties due to large gaps in the shells. However, most studies focus on integrated capsules, whereas little attention has been paid to the ruptured counterparts. Herein, an explosive bomb-inspired method was employed to prepare collapsed and ruptured Fe O /nitrogen-doped carbon (CR-Fe O /NC) capsules by using polystyrene (PS) nanoparticles (NPs) as a hard template, and polypyrrole (PPy) with embedded Prussian blue (PB) NPs as the shell. During pyrolysis, PB is converted into Fe O , and PPy is carbonized to form NC. Importantly, the PS core decomposes into gas molecules, leading to high pressure inside of the capsule, which explodes the thin shell into pieces. The roles of shell thickness and amount of Fe O on determining the spherical or collapsed, and integrated or ruptured morphology were revealed. Taking advantage of structural merits, including large gaps, thin shells, low density, and high surface area, CR-Fe O /NC capsules were used as supports for Pd NPs. These capsules exhibited better catalytic activity than that of integrated ones. Due to the magnetic properties, they could be reused at least five times.
与完整胶囊相比，破裂的胶囊由于壳层存在较大间隙，具有更好的质量扩散和传输性能。然而，大多数研究集中在完整胶囊上，而对破裂的胶囊关注较少。在此，采用一种受炸弹启发的方法，以聚苯乙烯（PS）纳米颗粒（NPs）为硬模板，以嵌入普鲁士蓝（PB） NPs的聚吡咯（PPy）为壳层，制备塌陷和破裂的Fe₃O₄/氮掺杂碳（CR-Fe₃O₄/NC）胶囊。在热解过程中，PB转化为Fe₃O₄，PPy碳化形成NC。重要的是，PS核分解为气体分子，导致胶囊内部压力升高，从而使薄壳爆炸成碎片。揭示了壳层厚度和Fe₃O₄含量在决定球形或塌陷、完整或破裂形态方面的作用。利用其结构优点，包括大间隙、薄壳、低密度和高比表面积，CR-Fe₃O₄/NC胶囊被用作钯纳米颗粒的载体。这些胶囊表现出比完整胶囊更好的催化活性。由于具有磁性，它们可以重复使用至少五次。
