Pressure-Induced Controllable Multicolor Emission in Ethyl 7-hydroxy-2-oxo-2H-chromene-3-carboxylate

Area of Science:

• Materials Science
• Organic Chemistry
• Spectroscopy

Background:

• Organic piezochromic materials are crucial for pressure-sensing applications.
• High sensitivity and color contrast are essential for practical use.

Purpose of the Study:

• To investigate the piezochromic behavior and phase transition of ethyl 7-hydroxy-2-oxo-2H-chromene-3-carboxylate (EHC).
• To evaluate EHC's potential as a colorimetric pressure sensor.

Main Methods:

• Studied the piezochromic response of EHC under varying pressure conditions.
• Analyzed phase transitions and their effect on optical properties.

Main Results:

• EHC undergoes a pressure-induced phase transition at 1.0 GPa.
• Exhibits multicolor emission shifts from blue to green and yellow with increasing pressure.
• Sensitivity increased from 1.12 nm·GPa⁻¹ to 11.63 nm·GPa⁻¹ and color contrast from 1 nm to 186 nm post-transition.

Conclusions:

• EHC demonstrates excellent potential as a colorimetric sensor for external pressure.
• Enhanced intermolecular interactions, particularly π-π interactions, drive the improved performance.
• Provides insights into structure-property relationships for developing new piezochromic materials.