An n-type semiconducting diazaporphyrin-based hydrogen-bonded organic framework

Area of Science:

• Materials Science
• Organic Chemistry
• Nanotechnology

Background:

• Developing materials with both high electrical conductivity and permanent porosity is a significant challenge.
• Diazaporphyrin complexes offer potential for functional porous materials.
• Hydrogen-bonded organic frameworks (HOFs) are a class of porous materials held together by non-covalent interactions.

Purpose of the Study:

• To synthesize and characterize a diazaporphyrin-based hydrogen-bonded organic framework (HOF).
• To investigate the electrical conductivity and charge-carrier mobility of the developed HOF.
• To elucidate the role of hydrogen bonding in the material's properties.

Main Methods:

• Synthesis of a 5,15-diazaporphyrin Ni(ii) complex with carboxyphenyl groups.
• Formation of a hydrogen-bonded organic framework (HOF) via hydrogen-bonding interactions.
• Characterization of thermal and chemical stability using powder X-ray diffraction (PXRD).
• Determination of charge-carrier mobility using flash-photolysis time-resolved microwave conductivity (FP-TRMC).

Main Results:

• A diazaporphyrin-based HOF with porosity and n-type semiconductivity was successfully synthesized.
• The HOF exhibited a charge-carrier mobility of 2.0 × 10^-7 m² V^-1 s^-1.
• An analogous diazaporphyrin lacking the HOF structure showed 20 times lower mobility.
• The HOF demonstrated good thermal and chemical stability.

Conclusions:

• Hydrogen-bonding networks are crucial for creating conductive pathways in porous materials.
• The developed diazaporphyrin-based HOF is a promising material for applications requiring conductivity and porosity.
• The study highlights the importance of supramolecular assembly in tuning material properties.