Global Centre for Environmental Remediation (GCER), Faculty of Science , The University of Newcastle , Callaghan , NSW 2308 , Australia.
Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), ATC Building , The University of Newcastle , Callaghan , NSW 2308 , Australia.
Langmuir. 2018 Nov 13;34(45):13584-13596. doi: 10.1021/acs.langmuir.8b00792. Epub 2018 Nov 5.
Hollow porous silica nanospheres (HSNs) are emerging classes of cutting-edge nanostructured materials. They have elicited much interest as carriers of active molecule delivery due to their amorphous chemical structure, nontoxic nature, and biocompatibility. Structural development with hierarchical morphology is mostly required to obtain the desired performance. In this context, large through-holes or pore openings on shells are desired so that the postsynthesis loading of active-molecule onto HSNs via a simple immersion method can be facilitated. This study reports the synthesis of HSNs with large through-holes or pore openings on shells, which are subsequently termed bowl-structured hollow porous silica nanospheres (BHSNs). The synthesis of BHSNs was mediated by the core-shell interfaces of the core-shell corona-structured micelles obtained from a commercially available ABC triblock copolymer (polystyrene- b-poly(2-vinylpyridine)- b-poly(ethylene oxide) (PS-P2VP-PEO)). In this synthesis process, polymer@SiO composite structure was formed because of the deposition of silica (SiO) on the micelles' core. The P2VP block played a significant role in the hydrolysis and condensation of the silica precursor, i.e., tetraethylorthosilicate (TEOS) and then maintaining the shell's growth. The PS core of the micelles built the void spaces. Transmission electron microscopy (TEM) images revealed a spherical hollow structure with an average particle size of 41.87 ± 3.28 nm. The average diameter of void spaces was 21.71 ± 1.22 nm, and the shell thickness was 10.17 ± 1.68 nm. According to the TEM image analysis, the average large pore was determined to be 15.95 nm. Scanning electron microscopy (SEM) images further confirmed the presence of large single pores or openings in shells. These were formed as a result of the accumulated ethanol on the PS core acting to prevent the growth of silica.
中空多孔硅纳米球（HSNs）是一类新兴的前沿纳米结构材料。由于其非晶态化学结构、无毒性质和生物相容性，它们作为活性分子输送载体引起了广泛关注。为了获得所需的性能，通常需要进行具有分级形态结构的结构开发。在这种情况下，希望壳层上具有大的通孔或孔开口，以便可以通过简单的浸渍法将活性分子后合成载入 HSNs。本研究报告了具有壳层上大通孔或孔开口的 HSNs 的合成，随后将其称为碗状中空多孔硅纳米球（BHSNs）。BHSNs 的合成是通过从市售的 ABC 三嵌段共聚物（聚苯乙烯- b-聚（2-乙烯基吡啶）- b-聚（环氧乙烷）（PS-P2VP-PEO）获得的核壳冠状结构化胶束的核壳界面介导的。在该合成过程中，由于二氧化硅（SiO）在胶束核上的沉积，形成了聚合物@SiO 复合结构。P2VP 嵌段在二氧化硅前体（即四乙氧基硅烷（TEOS））的水解和缩合过程中发挥了重要作用，然后维持了壳层的生长。胶束的 PS 核构建了空隙空间。透射电子显微镜（TEM）图像显示出具有平均粒径为 41.87 ± 3.28nm 的球形中空结构。空隙空间的平均直径为 21.71 ± 1.22nm，壳层厚度为 10.17 ± 1.68nm。根据 TEM 图像分析，平均大孔确定为 15.95nm。扫描电子显微镜（SEM）图像进一步证实了壳层中存在大的单个孔或开口。这些是由于 PS 核上积累的乙醇阻止了二氧化硅的生长而形成的。
