Nanomechanics of low-dimensional materials for functional applications

When materials’ characteristic dimensions are reduced to the nanoscale regime, their mechanical properties will vary significantly to that of their bulk counterparts. Recently low-dimensional materials, including one-dimensional (1D) and two-dimensional (2D) nanomaterials, have attracted the widespread attention of academia and industry because of their unique (e.g., thermal, optical, electrical, catalytic) properties. These outstanding properties give them a wide variety of functional applications; however, reliable devices and practical applications call for high structural reliability and mechanical robustness of these nanoscale building blocks. Therefore, there is a need to investigate and characterize the nanomechanical properties and deformation mechanisms of low-dimensional materials but this remains highly challenging. In this Focus article, we summarize the recent progress made in the nanomechanical studies on some representative 1D/2D crystalline nanomaterials, with a special emphasis on experimental research. Furthermore, the unconventional mechanical properties, such as the significantly enhanced elasticity, of these low-dimensional crystals can lead to unprecedented physical and chemical property changes, which may fundamentally change the way such materials conduct electricity/heat, transmit/emit light, and their involvement in chemical reactions. Therefore, the nanomechanical approach can be also used to tailor the materials’ functional properties and performance, by so-called strain engineering, which can open up new avenues to explore how devices can be designed and fabricated with even more dramatic changes in low-dimensional crystalline materials for information processing, communications, biomedical, and energy applications.