Artificial super skin with flexible organic transistor  (Source: L.A. Cicero)
Solar cells can stretch up to 30 percent beyond its normal length and will power the artificial electronic super skin

A Stanford University researcher has created "super skin," which now utilizes flexible solar cells capable of stretching up to 30 percent beyond their normal length. 

Zhenan Bao, study leader and a Stanford University researcher, and a team of scientists from Stanford, have improved Bao's super skin by adding flexible solar cells that can stretch. 

Bao originally created the artificial super skin with a flexible organic transistor, which is made with carbon-based materials and flexible polymers. This transistor allows the super skin to detect pressure and touch through a highly elastic and thin rubber layer, which looks like a grid of small inverted pyramids. There are up to 25 million of these pyramids per square centimeter. This layer changes thickness when pressure is applied to it, which changes the flow through the transistor. 

Now, Bao is looking to add two new abilities to her artificial super skin. The first is a way of detecting chemicals and different kinds of biological molecules. The second is the addition of flexible solar cells that can generate electricity and stretch. 

To make the super skin sense certain biological molecules, the surface of the transistor is coated with another molecule in order to allow the first biological molecule to bind to it. This process was used to sense a certain kind of DNA, and can also be used to detect chemicals by simply adjusting certain parts of the transistor's structure. This makes the super skin capable of sensing chemical substances in liquid or vapor environments. 

"Depending on what kind of material we put on the sensors and how we modify the semiconducting material in the transistor, we can adjust the sensors to sense chemicals or biological material," said Bao. 

Bao is also working to make the super skin detect proteins so that it can be useful in the medical field. 

"For any particular disease, there are usually one or more specific proteins associated with it - called biomarkers - that are akin to a 'smoking gun' and detecting those protein biomarkers will allow us to diagnose the disease," said Bao.

In order to detect any biological molecule or chemical substance, the super skin has to transmit electronic signals to send data to the computer or human brain, depending on the processing center. To do this, Bao will use flexible solar cells, which run on the sun's energy and makes it so batteries are not required. This will help the sensors obtain better mobility. Also, the solar cells have a "wavy" microstructure that stretches when pulled, and a liquid metal electrode conforms to this type of surface whether it is stretched or relaxed, generating electricity at a continuous rate. The skin can stretch up to 30 percent beyond its normal length. 

"One of the applications where stretchable solar cells would be useful is in fabrics for uniforms and other clothes," said Darren Lipomi, a graduate student in chemical engineering in Bao's lab. 

"There are parts of the body, at the elbow for example, where movement stretches the skin and clothes. A device that was only flexible, not stretchable, would crack if bonded to parts of machines or of the body that extend when moved."

In addition, Bao sees the super skin being used on robots.

"You can imagine a robot hand that can be used to touch some liquid and detect certain markers or a certain protein that is associated with some kind of disease and the robot will be able to effectively say, 'Oh, this person has that disease,'" said Bao. "Or the robot might touch the sweat from somebody and be able to say, 'Oh, this person is drunk.'"

This study is published in Advanced Materials.

"I'm an Internet expert too. It's all right to wire the industrial zone only, but there are many problems if other regions of the North are wired." -- North Korean Supreme Commander Kim Jong-il
Related Articles

Latest Blog Posts

Copyright 2017 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki