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The self‐healing capability is highly desirable in semiconductors to develop advanced devices with improved stability and longevity. In this study, the automatic self‐healing in silicon nanowires is reported, which are one of the most important building blocks for high‐performance semiconductor nanodevices. A recovery of fracture strength (10.1%) on fractured silicon nanowires is achieved, which is demonstrated by in situ transmission electron microscopy tensile tests. The self‐healing mechanism and factors governing the self‐healing efficiency are revealed by a combination of atomic‐resolution characterizations and atomistic simulations. Spontaneous rebonding, atomic rearrangement, and van der Waals attraction are responsible for the self‐healing in silicon nanowires. Additionally, the self‐healing efficiency is affected by the fracture surface roughness, the nanowire size, the nanowire orientation, and the passivation of dangling bonds on fracture surfaces. These new findings shed light on the self‐healing mechanism of silicon nanowires and provide new insights into developing high‐lifetime and high‐security semiconductor devices. [ABSTRACT FROM AUTHOR]

Lithium-ion migration at the WO 3 /electrolyte interface is governed by the phase transformation mechanism by which metastable states are replaced from one phase to another. Herein, an in situ single nanowire-based cell is constructed to investigate the dynamic phase transformation and morphology evolution of h-WO 3 nanowire in real-time during its deep lithiation. One of the most significant features of h-WO 3 lithiation is the irreversible transformation from h-WO 3 to Li 2 WO 4. There are a large number of deep ion-trapping sites composed of 4 O atoms in Li 2 WO 4 crystal structure, that is, inserted lithium ions are irreversibly bound in these traps and nearly cannot be deintercalated. A mechanism on irreversible WO 3 -to-Li 2 WO 4 transformation in deep lithiation reaction is demonstrated. With the aid of in situ transmission electron microscopy, we controllably triggered lithium-ion migration at the WO 3 /electrolyte interface and directly visualized the nanoscale lithium-ion migration as a stop motion movie. Hexagonal WO 3 irreversible transformation to Li 2 WO 4 can be experimentally demonstrated via in situ HRTEM in the deep lithiation process including the initial activation of the lithium metal, the wetting of a single WO 3 nanowire and the migration of lithium ions into WO 3 , and the restructuring of hexagonal WO 3. [Display omitted] [ABSTRACT FROM AUTHOR]