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. When materials' characteristic dimensions are reduced to the nanoscale regime, their mechanical properties will vary significantly to that of their bulk counterparts.