State Key Laboratory of Materials Processing and Die & Mould Technology, Key Laboratory of Material Chemistry for Energy Conversion and Storage of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
Adv Sci (Weinh). 2022 Sep;9(25):e2202394. doi: 10.1002/advs.202202394. Epub 2022 Jul 3.
Mesoporous carbon microparticles (MCMPs) with anisotropic shapes and ordered structures are attractive materials that remain challenging to access. In this study, a facile yet versatile route is developed to prepare anisotropic MCMPs by combining neutral interface-guided 3D confined self-assembly (3D-CSA) of block copolymer (BCP) with a self-templated direct carbonization strategy. This route enables pre-engineering BCP into microparticles with oblate shape and hexagonal packing cylindrical mesostructures, followed by selective crosslinking and decorating of their continuous phase with functional species (such as platinum nanoparticles, Pt NPs) via in situ growth. To realize uniform in situ growth, a "guest exchange" strategy is proposed to make room for functional species and a pre-crosslinking strategy is developed to preserve the structural stability of preformed BCP microparticles during infiltration. Finally, Pt NP-loaded MCMPs are derived from the continuous phase of BCP microparticles through selective self-templated direct carbonization without using any external carbon source. This study introduces an effective concept to obtain functional species-loaded and N-doped MCMPs with oblate shape and almost hexagonal structure (p6mm), which would find important applications in fuel cells, separation, and heterogeneous catalysis.
具有各向异性形状和有序结构的介孔碳微球(MCMPs)是一种很有吸引力的材料,但很难获得。在这项研究中,通过将嵌段共聚物(BCP)的中性界面引导的 3D 受限自组装(3D-CSA)与自模板直接碳化策略相结合,开发了一种简单而通用的方法来制备各向异性 MCMPs。该方法能够将 BCP 预先设计成具有扁球形和六方堆积柱状介观结构的微球,然后通过原位生长,选择性地交联并在其连续相中修饰功能物种(如铂纳米粒子,Pt NPs)。为了实现均匀的原位生长,提出了“客体交换”策略,为功能物种腾出空间,并开发了预交联策略,以在渗透过程中保持预形成的 BCP 微球的结构稳定性。最后,通过选择性自模板直接碳化,从 BCP 微球的连续相中去除功能物种,得到负载 Pt NP 的 MCMPs,而无需使用任何外部碳源。该研究引入了一个有效的概念,用于获得具有扁球形和几乎六方结构(p6mm)的负载功能物种和 N 掺杂的 MCMPs,这将在燃料电池、分离和多相催化等领域得到重要应用。