A strategy towards efficient mechanochromic luminogens with high contrast is developed. The twisted propeller-like conformations and effective intermolecular interactions not only endow the luminogens with AIE characteristics and high efficiency in the crystalline state, but also render them to undergo conformational planarization and disruption in intermolecular interactions upon mechanical stimuli, resulting in remarkable changes in emission wavelength and efficiency.

Triphenylacrylonitrile and diarylamine based D-π-A luminogens exhibit typical AIE characteristics with high solid state efficiency up to unity and switchable mechanochromism with high contrast, which render them multifunctional materials for versatile applications in optical storage, volatile organic compound (VOC) detection, OLEDs, etc.

CzCNDSB with a highly twisted conformation in the solid state is constructed. Single crystal measurements prove that it possesses an inside pore with a diameter of 8 Å and further forms a long-range orderly arrayed channel. CzCNDSB can sense external pressure from 1.0 atm to 9.21 GPa, accompanied by color changes from green to red with excellent reversibility and reproducibility.

Organic field-effect transistors (OFETs) based on an aggregation-induced emission (AIE) material were fabricated using a calcium-gold asymmetric electrode system. The devices showed very high and balanced mobility, reaching 2.50 and 2.10 cm(2) V(-1) s(-1), respectively, for electron and hole. Strong green electroluminescence from the single-crystal side edge was observed from all the devices. This work demonstrates that AIE active materials could not only achieve high luminescence, but also be used in light emitting transistors and achieve very high mobility.