In Situ Interfacial Sublimation of Zn₂GeO₄ Nanowire for Atomic-Scale Manufacturing

Sublimation as the motion behavior of surface atoms plays a vital role in tailoring the structure and properties of materials for atomic-scale manufacturing. Revealing the thermodynamics of sublimation atomically is critical to understanding the unique properties of nanostructured materials and manufacturing technologies at the atomic scale. However, atomic-scale manipulation of the sublimation pathway and reveal of the sublimation mechanism are still a challenge, especially for complex oxide systems. Here, the sublimation kinetics of a Zn2GeO4 (ZGO) nanowire is studied atomically at elevating temperature by using the in situ transmission electron microscope. A nanosized thermal heating cell is formed by coating the ZGO with a carbon shell, where the nanowire can be sublimated at high temperatures. Different ZGO sublimation stages with size-dependent anisotropic layer-by-layer sublimation and surface atom reconstruction (quasi-liquid behavior) are clearly observed. The in situ technique offers a quantitative method of investigating the thermal dynamics of nanomaterials, an essential experimental basis for future atomic-scale manufacturing at high temperatures.