The molecular imaging reveals hidden defects in plastics used for the electronics

A new study reveals that insights into the educated plastic materials used in electronics and how hidden defects in their structure could restrict their performance.

Conjugated polymers are a kind of plastic that run electricity and are used in optoelectronics, computers, biosensors and electricity generation. The materials are light, inexpensive and can be printed on flexible substrates in thin layers, which means that they are ideal for the next generation technologies.

An international team of scientists examined a popular method for the production of polymers called Aldol condensation, which is praised as versatile, metal-free, environmentally friendly and scalable.

The scientists published their results Natural communicationAnd shows that this synthesis method introduces structural defects that could have an impact on how well the polymer electricity carries out or converts heat into thermoelectric devices into electrical energy.

The senior author Professor Giovanni Costantini from the University of Birmingham commented: “The Aldol condensation process can generate defects in the polymer sequences, as failed in a molecular dance, which can disturb the flow of electrons to reduce the electrons and reduce reliability in the derivations. Trust in rare or poisonous metals in the Manufacture. “

These defects have so far not been taken into account together with the secondary response paths they produce, especially because conventional analytical techniques they cannot prove.

The researchers used a powerful imaging technology called Scan -Tunneling -Mikroscopy (STM), combined with electrospray deposition (ESD) – and thus the examination of polymers on a molecular level – zooming, as the building blocks were connected, a molecule at a time.

They examined four different polymers made with Aldol condensation and discovered two main types of defects:

• Coupling defects – these are like kinks or bends in the polymer chain, which are caused by the building blocks, which are connected in the wrong orientation or position.
• Sequence errors – These occur when the order of the building blocks is wrong, like two of the same blocks in a row if they are supposed to change.

By adapting the chemical design and cleaning the building blocks before polymerization, the researchers were able to significantly reduce the number of defects.

One approach was to use the Aldol condensation to create small, well-defined molecules, which were then linked to a different method with much cleaner polykettes.

“This is an important step forward to understand how you can achieve better materials for electronics,” added Professor Costantini. “It shows that even green chemistry needs careful control to achieve the best results.”