Stress-induced CsPbBr₃ nanocrystallization on glass surface: Unexpected mechanoluminescence and applications

In this work, we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline, due to the stress-induced precipitation of CsPbBr₃ perovskite nanocrystals on glass surface. It is revealed that, unlike the conventional thermal-induced phase transformation mechanism, the breakage of bonding of glass network provides the energy for nucleation and growth, and the shear stress avoids the long-range migration of structural units for crystallization. Such unique ML phenomenon enables the visualization of dynamical force that is inaccessible by common strategy, and so, opens up some novel applications, such as the pressure-sensitive "glassy pencil" to learn people's writing habits, and the Pb²⁺-detection with good sensitivity and selectivity. These findings not only demonstrate an effective route for the preparation of perovskite materials in a green, time-saving, low cost, and scalable way, enrich the knowledge of glass crystallization mechanism, but also exploit a useful avenue to quantitatively visualize the dynamical force.