Enhancing the Thermal Stability of Solution-Processed Small-Molecule Semiconductor Thin Films Using a Flexible Linker
Andrea Gasperini1, Xavier A Jeanbourquin1, Aiman Rahmanudin1
1Laboratory for Molecular Engineering of Optoelectronic Nanomaterials, École Polytechnique Fédérale de Lausanne (EPFL), Station 6, 1015, Lausanne, Switzerland.
Advanced Materials (Deerfield Beach, Fla.)
|August 26, 2015
Summary
Flexible aliphatic chains create polymeric semiconductors with enhanced crystallinity and thermal stability. These materials improve performance in field-effect transistors and solar-cell devices.
Area of Science:
- Materials Science
- Polymer Chemistry
- Organic Electronics
Background:
- Conjugated molecular semiconductors are crucial for organic electronic devices.
- Achieving high performance requires optimizing material properties like crystallinity and thermal stability.
- Traditional molecular semiconductors often face limitations in processability and long-term stability.
Purpose of the Study:
- To synthesize and characterize novel polymeric materials by linking conjugated molecular semiconductors with flexible aliphatic chains.
- To investigate the impact of extended covalent connectivity on the material's crystallinity and thermal properties.
- To evaluate the performance enhancement of these new polymeric materials as additives in organic electronic devices.
Main Methods:
- Synthesis of polymers incorporating defined conjugated segments and flexible aliphatic linkers.
- Characterization of thermal properties using thermogravimetric analysis and differential scanning calorimetry.
- Assessment of crystallinity through X-ray diffraction.
- Fabrication and testing of organic electronic devices, including field-effect transistors and bulk heterojunction solar cells, using the synthesized polymers as additives.
Main Results:
- The synthesized polymeric materials exhibit improved crystallinity compared to their monomeric counterparts.
- Enhanced thermal stability was observed due to the extended covalent connectivity provided by the aliphatic chains.
- Device performance, specifically in field-effect transistors and bulk heterojunction solar cells, showed significant improvement when these polymers were used as additives.
- The defined conjugated segments were maintained, ensuring efficient charge transport.
Conclusions:
- Linking conjugated molecular semiconductors with flexible aliphatic chains is an effective strategy to create high-performance polymeric materials.
- The resulting materials offer a promising combination of processability, crystallinity, and thermal stability for organic electronics.
- These novel polymers represent a valuable advancement for improving the efficiency and durability of field-effect transistors and solar-cell devices.
