Janus particles, in which two distinct compositions are integrated, have attracted considerable interest for their potential multi-functionalities and synergistic effects. Although seed-mediated growth appears to be a suitable strategy that meets the stringent specifications for obtaining Janus particles, it is inapplicable to guide the growth of two crystalline components with different crystal structures. Herein, the formation of Janus particles via phase segregation is proposed. As proof-of-concept, promising photon conversion materials, ScF₃ and lanthanide (Ln) fluorides, with great differences in structure, were chosen to build a series of Janus particles. Interestingly, using heavy (Lu, Yb, Dy and Tb) and light (Pr, Nd, Sm, Eu and Gd) lanthanides, ScF₃–LiLnF₄ and ScF₃–LnF₃ were formed, respectively. Time-dependent reaction studies indicate that phase segregation paves the way for the formation of these Janus nanoparticles (NPs), and this speculation is further confirmed by in situ transmission electron microscopy observations. These investigations provide new insights for the synthesis of heterostructured materials.

中文翻译：

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相分离可实现氟化scan-氟化镧Janus纳米粒子†

整合了两种不同成分的Janus颗粒，由于其潜在的多功能性和协同作用而引起了极大的兴趣。尽管种子介导的生长看来是满足获得Janus颗粒的严格规范的合适策略，但它不能指导两个具有不同晶体结构的晶体组分的生长。在此，提出了通过相分离形成Janus颗粒的方法。作为概念验证，选择了有前途的光子转换材料ScF ₃和氟化镧（Ln），它们在结构上存在很大差异，从而构建了一系列Janus粒子。有趣的是，使用重（Lu，Yb，Dy和Tb）和轻（Pr，Nd，Sm，Eu和Gd）镧系元素，ScF ₃分别形成-LiLnF ₄和ScF ₃ -LnF ₃。随时间变化的反应研究表明，相分离为这些Janus纳米颗粒（NPs）的形成铺平了道路，这一推测得到了现场透射电子显微镜观察的进一步证实。这些研究为异质结构材料的合成提供了新的见识。