Diemissive dye@CP composites with full-spectrum tunable mechanoluminescence

Abstract

The difficulty of precise control of the luminescence colour before and after grinding of mechanoluminescence (MCL) materials has limited their practical applications. Herein we report a doping dye control strategy to regulate the MCL colour. A one-dimensional (1D) coordination polymer (CP) (2) and various dye@2 composites were conveniently prepared through H₂O-mediated structural transformation of a 2D CP (1). The diemissive composites have interesting MCL behaviors. Visible light full-spectrum precise control of the luminescence colour before and after grinding can be realized in the composites by adjusting both the type and the amount of the captured dyes. Such a strategy also makes the materials have an obvious difference in the luminescence colours before and after grinding. Detailed study reveals that the aggregation caused quenching effect and solid solvent dilution effect of the dyes, as well as the low-dimensional close-packed structure of the CP matrix, play an important role in the luminescence colour control. Besides, the composites also have interesting thermoluminescence properties. Combining the encryption principle of the Hill cipher with the MCL and thermoluminescence properties of the composites, a new triple information encryption method can be developed. This work provides a convenient and low-cost strategy for preparing MCL materials with the desired luminescence colour.