TAGS: Electrical & Electronics Green and Bioplastics New Energy Solutions
Researchers from the University of Groningen have developed a new class of polymers based on protein-like materials and inspired by spider silk, that work as proton conductors and might be useful in future bio-electronic devices.
More Active Groups, More Conductivity
The researcher group headed by Dr. Giuseppe Portale have developed a robust membrane using a spider silk inspired polyelectrolyte that is capable of efficiently transport protons.
The first goal was to prove that researchers could precisely tune the proton conductivity of the protein-based polymers by tuning the number of ionic groups per polymer chain. Many unstructured biopolymers that had different numbers of ionizable carboxylic acid (-COOH) groups were prepared. Their proton conductivity scaled linearly with the number of charged carboxylic acid groups per chain.
“It was not ground-breaking as everybody knows this concept. We were thrilled by the possibility to design something that worked as expected,” Portale says.
After experimenting with different polymer options, researchers landed on a natural polymer, spider silk. The newly developed material self-assembles at the nanoscale similarly to spider silk while creating dense clusters of charged groups, which are very beneficial for the proton conductivity. Researchers were able to turn it into a robust centimeter-sized membrane. The measured proton conductivity of the membrane is one order of magnitude higher than those of any previously known biomaterials.
Applications in Future Energy Devices
In order to really apply this material, researchers need to improve it and make it processable. But even though the work is not yet done, Dr. Giuseppe Portale and his co-workers can already dream about applying their polymer. This material could be useful as a membrane in future energy devices. Maybe not for the large-scale systems that is seen in cars and factories, but more on a small scale. There is a growing field of implantable bio-electronic devices, for instance glucose-powered pacemakers.
“The conductivity we measure in our material is influenced by the environment, like humidity, volatile chemical species or temperature. So, changes in all these quantities can be measured using our material,” said Portale.
Source: University of Groningen