Harnessing Truxone-Based Electrically Conductive Metal-Organic Framework for Electrochromism

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) offer tunable electrochromic properties via redox-active components.
• Poor electrical conductivity in MOFs limits redox activity and necessitates high operating voltages, hindering device integration.
• Electrically conductive MOFs (c-MOFs) can improve conductivity but often lack sufficient redox-active organic functional groups.

Purpose of the Study:

• To develop a c-MOF with linker-centric electrochromism.
• To demonstrate efficient electrochromic switching at low voltages.
• To explore the potential of c-MOFs with redox-active functional groups in linkers for advanced applications.

Main Methods:

• Utilized Cu-truxone, a c-MOF with a conductivity of 1.9 × 10^-2 S cm^-1, featuring redox-active carbonyl (C═O) groups.
• Developed an in situ growth method for direct synthesis of Cu-truxone on a mercaptobenzoic acid-functionalized fluorine-doped tin oxide (FTO) substrate.
• Investigated electrochromic properties, including switching voltage and coloration efficiency.

Main Results:

• Achieved pronounced and efficient electrochromic switching in Cu-truxone.
• Demonstrated operation within a low voltage range (<1.0 V).
• Obtained a high coloration efficiency of 193.6 cm² C^-1.

Conclusions:

• Cu-truxone, a c-MOF with redox-active carbonyl groups in linkers, enables efficient linker-centric electrochromism.
• The in situ growth method facilitates low-voltage electrochromic device operation.
• Redox-active functional groups in c-MOF linkers show significant potential for electrochromic applications.