Janus Dendrimers for Drug Delivery Supramolecular Approaches to Semiconducting Devices

 

Hybrid Oligomers

Structure-property relationship study of novel furan-based semiconductors for electronic devices


Conjugated organic materials are of great interest because of their applications in optoelectronic devices, such as organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), and organic photovoltaics (OPV). Thiophene containing molecules are the most commonly used organic materials because of their superior electronic properties. However, oligothiophenes tend to suffer from low rigidity and inefficient luminescence.  Recently, studies have emerged focusing on their close analogues, oligofurans. Replacement of the sulfur atom with oxygen yields electron-rich oligomers exhibiting tighter solid-state packing and greater rigidity than oligothiophenes. In addition, furan derivatives have been synthesized from a variety of natural products making them a renewable and sustainable synthetic resource. Unfortunately, despite recent interest, oligofurans as viable semiconducting materials are still understudied. Furans are relatively unstable, undergoing oxygen and light induced decomposition. Thus, there remains an ongoing challenge to develop new compounds that surpass the electronic properties of well known oligothiophenes. 

 

Thiophene-based materials

Thiophene-based materials

Advantages

  • Good charge mobility
  • High polarizability of sulfur atoms
  • Strong intermolecular interactions

Disadvantages

  • Relatively low solubility
  • Low rigidity

 

Furan-based materials

Furan-based materials

Advantages

  • Prepared from biorenewable sources
  • Greater rigidity
  • Better solubility
  • Tighter packing
  • More efficient fluorescence

Disadvantages

  • Light/Oxygen sensitive

 

The objective of this research is to design, synthesize, and characterize extended families of furan-based semiconductors .  The incorporation of thiophenes to form fused and alternating hybrid systems reduces the decomposition of the furan while lowering the HOMO-LUMO gap and increasing the planarity of conjugated system. By tailoring the electronic and solid-state properties of oligofurans through structural modification, the extent of conjugation and charge delocalization can be tuned. Along with computational methods and photophysical characterization, we can guide the modularity of their design and synthesis.