Sep 7 2017
A team of Researchers from the University of Houston and China have developed a new type of electronic device that can be activated to dissolve when exposed to water molecules in the atmosphere.
Cunjiang Yu, Bill D. Cook Assistant Professor of mechanical engineering, center, and co-first authors Xu Wang, left, and Kyoseung Sim, right. (Credit: University of Houston)
The research shows potential for biomedical devices that dissolve within the body and eco-friendly disposable personal electronics. There are also defense applications, including devices that can be programmed to dissolve so as to protect sensitive information, said Cunjiang Yu, Bill D. Cook Assistant Professor of Mechanical Engineering at the University of Houston and the paper’s Lead Author. The research paper has been published in Science Advances.
The field, known as physically transient electronics, presently requires immersion in biofluids or aqueous corrosive solutions. Yu said this research shows a totally new working mechanism – the dissolution is activated by ambient moisture.
More importantly, the transient period of time can be precisely controlled.
Cunjiang Yu, Lead Author and Bill D. Cook Assistant Professor of Mechanical Engineering, the University of Houston
That means a biomedical implant could be engineered to vanish when its function – delivering medication, for instance – is done. Sensitive communications could be programmed to literally disappear once the message was delivered.
No more will old cell phones be littering kitchen drawers. New versions could be devised to dissolve when they are not needed any more.
“We demonstrate that polymeric substrates with novel degradation kinetics and associated transience chemistry offer a feasible strategy to construct physically transient electronics,” the Researchers wrote. “Through the manipulation of the polymer component and environmental humidity, the progress of hydrolyzing polyanhydrides can be managed and thus the dissolution kinetics of (a) functional device can be controlled.”
The time period can span from days to weeks, or perhaps longer, they said.
The model built by the team works like this: Functional electronic parts were fabricated via additive processes onto a film composed of the polymer polyanhydride. The device stayed stable until ambient moisture activated a chemical breakdown that digested the inorganic electronic materials and parts.
The Researchers analyzed several compounds, including aluminum, nickel indium-gallium, zinc oxide, copper and magnesium oxide, and developed a range of electronic devices, including capacitors, antennas, transistors, resistors, photo sensors, diodes and more, to exhibit the versatility of the model.
The lifespan of the devices can be maintained by changing the humidity level or by altering the polymer composition, Yu said.
Besides Yu, authors on the research paper include Yang Gao, Xu Wang, Kyoseung Sim, Jingshen Liu and Ji Chen, all from UH, and Ying Zhang and Hangxun Xu of the University of Science and Technology of China.