Znak Politechniki Warszawskiej

Do Flexible Electrodes Make Life Easier?

Grzegorz Wróblewski (on the right) is a member of the research team of the Department of Microtechnology and Nanotechnology, Faculty of Mechatronics

A cell phone falls on the floor. It works, but the cracked screen resembles a spider’s web. This and similar damage can be prevented by using flexible electrodes created by Grzegorz Wróblewski, PhD (Eng.) from the Faculty of Mechatronics at the Warsaw University of Technology.

He first began conducting research for his Master’s Thesis. “The results were quite promising”, says Wróblewski. “Then I realized that I’d like to remain at the University and pursue a doctorate”.

To Print Electronics

However, the flexible electrode was not invented for use in phones, tablets, or computers. Wróblewski is a member of the research team of the Department of Microtechnology and Nanotechnology, Faculty of Mechatronics; its main area of expertise is printed electronics. “You can say that we print electronics like magazines”, he explained.

The team consists of 10-15 people. They are doctors and doctoral candidates working under the guidance of Professor Małgorzata Jakubowska.

Nowadays, printed electronics are mostly used to manufacture anti-theft devices for clothes (printed electronic labels), as well as membrane keyboards. However, the industry has a much larger potential. Printed electronics can represent an alternative to silicon technologies. Nevertheless, Wróblewski emphasises that they are not competing with them. “Let’s leave theoretical considerations”, he says. “We can’t print a processor with the same parameters as silicon processors. Printed electronics can be used in sensor surfaces, antennas, conductive circuits, resistors or capacitors. We can mass produce cheap and biodegradable structures. We don’t use cleanrooms or high temperatures, we don’t have sophisticated technological processes; we only focus on simple and efficient techniques”.

The team consists of 10-15 people. They are doctors and doctoral candidates working under the guidance of Professor Małgorzata Jakubowska.

The team consists of 10-15 people. They are doctors and doctoral candidates working under the guidance of Professor Małgorzata Jakubowska.

It’s All About the Ink

The flexible electrode, Wróblewski’s brainchild, is necessary to develop the printed electronics team’s projects. Thanks to the technique of spray coating, layers he obtained using it were over 10, or even 100 times thinner than when using screen printing.

Wróblewski mainly uses carbon nanotubes to manufacture the electrodes, as they are quite cheap today. “The method itself is not complicated, but there are a couple of details you need to feel”, he says. “It’s all about good ink. I worked on it for 3 years”.

Wróblewski explains that his work resembles painting a car. He calls the suspensions he uses inks. “They contain carbon nanotubes, graphene flakes, graphite nanofibres”, he tells us. “In a container, the ink is black, but, after spraying it, a translucent conductive layer appears”.

Innovator

Dr Wróblewski’s flexible electrode was recognized by the jury of the Innovators Under 35 competition, organized by “MIT Technology Review”, a magazine of the Massachusetts Institute of Technology. The programme has its editions in 22 countries. In Poland, these awards were granted for the second time. They went to 10 young scientists and entrepreneurs creating innovative projects that befit the challenges and issues of modern society. They were chosen from among 150 candidates. All finalists talked about their ideas during a ceremonial gala on 28 June 2016 in Warsaw.

Wróblewski was nominated for the competition by Innovation Hub. This was thanks to Aneta Michalska, a friend from the University, who knew what he was working on. “I sent the required information and forgot about the matter”, he says. “After a while, during one weekend, I received congratulations by phone”.

At the competition’s gala, the scientist from the WUT presented his idea by describing a cracked phone screen. “I selected this topic because it’s the easiest way to imagine the use of flexible electronics”, he explained.

Can we expect it to be used in screen manufacturing soon? “Let’s not focus on that”, says Wróblewski. “Current screens are made using ITO – indium tin oxide. Such layers are more transparent than ours, but also more fragile. Our layers, based on various carbon structures, can be folded 150 thousand times, and it won’t negatively affect their parameters. ITO is considerably damaged after only 10 fold cycles”.
All carbon electrodes are great in devices that have to be very flexible, and in large structures with complex shapes. It is also a great substrate with a richly developed surface, which can constitute a base for enzymes.

Printed Electronics Centre

Companies want to take advantage of the possibilities offered by Dr Wróblewski’s flexible electrode, and of the potential of printed electronics. The interest, especially after the Innovators Under 35 gala, is very high.

The entire printed electronics team at the WUT conducts intensive works in order to establish an appropriately equipped Printed Electronics Centre at the University, enabling moving research results from the proof-of-principle phase to higher technological levels.

 

Agnieszka Kapela

Promotion and Information Office