In situ structural engineering of two-dimensional nanomaterials at atomic scale

The miniaturization of silicon metal–oxide–semiconductor field-effect transistors has followed Moore's law for many years, but the channel and the gate dielectric layer are approaching their physical limits. Two-dimensional (2D) layered materials, with the atomic-scale thickness and rich physical properties, have gained attention as promising materials for next-generation transistors. Currently, many new candidate materials with unique properties have been explored and studied. However, due to some inherent limitations, there is growing interest in the rational engineering and predictable tuning of 2D nanomaterials. Significant attention is being directed towards modifying their pristine structure or engineering them into tailored architectures to meet the specific demands of various applications. Although some synthesis strategies can achieve the fabrication of materials with specific structures, high-precision structural engineering of low-dimensional materials remains a challenge. Here, due to the nanoscale control precision of transmission electron microscopy (TEM) and its ability to provide a visualization platform, some recent developments in achieving high-precision structural engineering of 2D materials are summarized. We hope these interesting manipulation strategies can help understand the underlying mechanism of the synthesis strategies and provide new insights for future structural engineering and property tailoring.