Recent progress in organic mechanoluminescent materials

Mechanoluminescence (ML) refers to the light emission from various organic and inorganic materials upon mechanical stimulus. As a new class of smart materials, mechanoluminescent materials are widely applicable for fluorescence switches, mechanosensors, security papers, optoelectronic devices and data storage etc. In the past few years, systematic investigations have been carried out, resulting in the production of a variety of mechanoluminescent materials. In this review, recent progress in pure organic mechanoluminescent materials is summarized, including mechanofluorescent and triboluminescent effects from conjugated small molecules.