Molecular dual-rotators with large consecutive emission chromism for visualized and high-pressure sensing

Low-cost, stable, highly sensitive, and easy-to-equip fluorescent high-pressure sensors are always attractive in both industrial and scientific communities. Organic emitting materials with pressure-dependent bathochromisms usually exhibit prominent mechanoluminescence, due to disturbance of intermolecular packing. This hinders their applications in stable and robust pressure sensing. In this work, we have developed a mechanically stable organic molecular pressure sensor, caused by intramolecular consecutive rotations by pressure, which exhibit large and eye-detectable emission bathochromism from yellow-green to red fluorescence and can be used for 0−15 GPa pressure sensing. The emission bathochromism shows good linear relationship with pressure, exhibiting a high linear coefficient of 9.1 nm/GPa. Moreover, this molecular sensor exhibits high thermal and mechanical stabilities, indicating good potentials for robust and outdoor applications.