Precisely controlling microstructure of colloidal particles is crucial for their applications. Core–shell colloids have been extensively synthesized and used in past decades. However, controlling the location of cores in core–shell particles remains a challenge. To address this problem we explored the synthesis of SiO₂-PS core–shell colloids by using a simple system containing only core particles, monomer, initiator, and water/ethanol and found the increase of ethanol/water ratio can induce a structure transition sequence from eccentric to concentric to eccentric to concentric to eccentric. Furthermore, we illustrate that the eccentric ratios of SiO₂-PS core–shell colloids, that is, the location of SiO₂ cores in the whole particles, can be precisely controlled by a two-step polymerization procedure. It is anticipated that our results can widen the application of core–shell colloids, especially after the introduction of functionality for core or shell materials.

中文翻译：

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偏心比可控的核壳型 SiO2-PS 胶体

精确控制胶体颗粒的微观结构对其应用至关重要。在过去的几十年中，核壳胶体已被广泛合成和使用。然而，控制核壳粒子中核的位置仍然是一个挑战。为了解决这个问题，我们通过使用仅包含核颗粒、单体、引发剂和水/乙醇的简单系统探索了 SiO ₂ -PS 核壳胶体的合成，发现乙醇/水比的增加可以诱导结构转变序列从偏心到偏心到偏心到偏心到偏心。此外，我们还说明了 SiO ₂ -PS 核壳胶体的偏心比，即 SiO 2 的位置_。整个颗粒中的核心，可以通过两步聚合程序精确控制。预计我们的结果可以扩大核壳胶体的应用，特别是在引入核壳材料的功能之后。