New innovations in the field of organic semiconductors could lead to the creation of more efficient LED TVs and flexible solar cells that can be cheaply manufactured.
Semiconductors work to convert electric currents to light; these devices are usually based on silicon, but this takes a huge amount of energy to produce, the University of Bath reported. The researchers believe they can overcome this problem through the use of organic semiconductors.
"Conventional semiconductor devices are tricky to make because they first require the production of crystalline materials. Because of this, they also use up a lot of energy to be produced," said Daniele Di Nuzzo, Research Officer in Physics at the University and first author on the paper. "In contrast, organic semiconductors can be processed via printing techniques. For example, organic semiconducting polymers can be dissolved in a solvent to make an electronic ink to be printed onto a surface. However they have a disordered structure and conduct electrical charges less well than silicon."
Scientists can improve the electrical properties of organic semiconductors by mixing them with "doping" molecules, which add electrical charges to the polymer.
"It's difficult currently to implement the doping technique in an effective way to produce organic semiconductor devices that work with high performances. Our research shows why this is the case and suggests how we can improve the performance of these materials," Di Nuzzo said.
The findings showed the size and geometrical position of the doping molecule had a significant effect on the efficiency of the semiconductor material. The organic polymer is composed of a chain of units that can be mixed with the doping molecule before it is printed onto a surface.
"Our work suggests that if you use a larger doping molecule, you limit the number of ways it can bind to the polymer, making the efficiency of the semiconductor more consistent."
The findings were published in a recent edition of the journal Nature Communications.