Mechanochromic Wide-Spectrum Luminescence Based on a Monoboron Complex

Area of Science:

• Materials Science
• Chemistry

Background:

• Mechanochromic luminescent materials offer dynamic color-changing properties.
• Developing materials with tunable luminescence and multiple interconvertible states is crucial for advanced applications.

Purpose of the Study:

• To describe a novel reversible mechanochromic luminescent material based on a tetrahedral monoboron complex.
• To investigate the material's distinct crystalline states and their luminescent properties.
• To explore the interconversion between different material states via mechanical and thermal stimuli.

Main Methods:

• Synthesis of a tetrahedral monoboron complex (B-1).
• Characterization of amorphous powder (P) and three crystalline states (A, B, C) using luminescence spectroscopy.
• Investigation of temperature-dependent luminescence and interconversion between states via grinding and heating.

Main Results:

• The monoboron complex (B-1) exhibits reversible mechanochromism with tunable green-to-red luminescence.
• Four distinct states (P, A, B, C) were identified, each with unique dual emission characteristics.
• One emission pathway shows a significant temperature-dependent increase, counteracting thermal quenching.
• All four states are interconvertible through mechanical force (grinding) and heat.

Conclusions:

• The described monoboron complex is a versatile mechanochromic luminescent material.
• The material's ability to exist in multiple interconvertible states allows for color writing and painting applications.
• The unique temperature-dependent luminescence offers potential for temperature-sensing or advanced display technologies.