High Thermopower in a Zn-Based 3D Semiconductive Metal-Organic Framework

Area of Science:

• Materials Science
• Chemistry
• Energy

Background:

• Conductive metal-organic frameworks (c-MOFs) are crucial for energy applications.
• Current research predominantly focuses on 2D c-MOFs, limiting exploration of 3D structures.
• Developing 3D c-MOFs is essential for unlocking new functionalities and properties.

Purpose of the Study:

• To synthesize and characterize a novel 3D conductive metal-organic framework (c-MOF).
• To investigate the thermoelectric properties of the new 3D c-MOF.
• To explore the potential of 3D c-MOFs in energy-related applications.

Main Methods:

• Synthesis of a 3D c-MOF using hexaaminobenzene and Zn(II), named Zn-HAB.
• Characterization of Zn-HAB's structure, porosity, and electronic band gap.
• Measurement of electrical conductivity, Seebeck coefficient, and power factor at 300 K.

Main Results:

• Zn-HAB exhibits microporosity and a band gap of approximately 1.68 eV.
• The material demonstrates a moderate conductivity of 0.86 mS cm^-1.
• A high Seebeck coefficient of 200 μV K^-1 and a power factor of 3.44 nW m^-1 K^-2 were recorded.

Conclusions:

• Zn-HAB is the first intrinsically conductive 3D MOF reported with thermoelectric properties.
• This work expands the synthetic strategies for 3D c-MOFs.
• The findings suggest significant potential for 3D c-MOFs in thermoelectric energy conversion.