Recently, heterostructure interfaced construction by binary metal selenide or metal oxide/metal selenide configuration has been attracting attention as anodes for sodium-ion batteries (SIBs). Especially, modification strategies such as formation of core–shell structure consisting of heterointerface can be a solution to resolve the issue of metal selenide electrodes. In this paper, new multicomponent metal compounds with heterointerface structure are firstly designed and suggested as anode for SIBs. The yolk-shell microsphere consisting of heterogeneous NiCo selenide@NiCo selenite core–shell nanospheres was prepared by spray pyrolysis and facile selenization and subsequently partial oxidation processes. NiCo selenide nanocrystals, which constitute the yolk-shell structure, are partially transformed into the NiCo selenide@NiCo selenite phase during the oxidation process. Notably, this process induces the nanoscale Kirkendall effect, leading to the transformation of the metal selenide nanocrystals into a hollow nanosphere morphology. As a result, the material adopts a hollow nanosphere structure with a NiCo selenide@NiCo selenite core–shell configuration. To the best of our knowledge, metal selenide@metal selenite core–shell configuration with hollow nanosphere is proposed for the first time. Heterointerface as well as yolk-shell structure consisting of hollow nanospheres showed synergistic effect for efficient and excellent sodium ion storage.

中文翻译：

---

由异质镍钴selenide@nickel亚硒酸盐核壳纳米球组成的蛋黄壳结构微球的合成及其在钠离子电池负极材料中的应用


近年来，由二元金属硒化物或金属氧化物/金属硒化物构型构成的异质结构界面结构作为钠离子电池 （SIB） 的负极引起了人们的关注。特别是，诸如形成由异质界面组成的核壳结构等修饰策略可以成为解决金属硒化物电极问题的解决方案。在本文中，首先设计了具有异质界面结构的新型多组分金属化合物，并建议将其作为 SIBs 的阳极。由异质 NiCo selenide@NiCo亚硒酸盐核壳纳米球组成的蛋黄壳微球是通过喷雾热解和简单的硒化以及随后的部分氧化过程制备的。构成蛋黄壳结构的 NiCo 硒化物纳米晶体在氧化过程中部分转化为 NiCo selenide@NiCo亚硒酸盐相。值得注意的是，这个过程诱导了纳米级 Kirkendall 效应，导致金属硒化物纳米晶体转变为空心纳米球形态。因此，该材料采用具有 NiCo selenide@NiCo 亚硒酸盐核壳配置的空心纳米球结构。据我们所知，首次提出了具有空心纳米球的金属selenide@metal亚硒酸盐核壳构型。异质界面以及由空心纳米球组成的蛋黄壳结构显示出高效和优异的钠离子储存的协同效应。