Light activated electrochemistry as reported by the Australian newspaper

Posted 1 December 2015

The Australian reported today on breakthrough research from the School of Chemistry UNSW on wireless electronics (see story here - requires subscription). ARC Laureate Fellow Prof. Justin Gooding and his co-workers recently reported on Connecting electrodes with light: one wire, many electrodes (Chemical Science 2015, 6, 6769).

To quote the Australian:

Researchers from the University of NSW have found a way of connecting electrodes with light instead of electrical wires. The “step change” breakthrough, reported in the journal Chemical Science, could overhaul electronics by removing the need to construct electrodes on rigid structures.

Team leader Justin Gooding said the new approach could be harnessed in biomedical sensors, generators, batteries and consumer electronics. But the standout applications lay in gadgets yet to be conceived.

“If you need a wire going to every electrode, you need pre-organised architecture,” said Professor Gooding, of the Centre of Excellence in Convergent Bio-Nano Science. “We can make an electrode that’s completely unstructured.

“Anywhere where flexibility is required, that will be a huge advantage. You can imagine someone saying, ‘I know what I can use this for!’.”

Professor Gooding said the requirement to wire up every electrode had been a central tenet of electronics ever since the field’s birth. Any device with 100 electrodes, for example, needs 100 wires to an external circuit. This adds to space requirements as well as demanding a rigid structure.

Under the new approach, the device needs just one wire to supply power, with the other electrodes connected using beams of light. “It’s the same principle used in photovoltaics,” Professor Gooding said. “In solar cells, they shine light and generate electricity. When we shine the light we’re using it to connect something.”

He said the electrodes were activated using a travelling light pointer, much like the laser beam in a compact disc player. The light forms temporary electrical connections at specific points of a “monolithic” semiconductor.

Researchers have had an “inkling” of the idea for years, he said. “We just stumbled across the surface chemistry that allowed us to do it on silicon. Basically, we take a piece of silicon and modify it with a single molecule-thick layer (which) stops (it) losing its electrical property.”

The team is using the approach to develop “capture and release” technology which allows biomedical researchers to collect cells simply by shining light on them. Professor Gooding said it would be a “powerful” tool when microscope observations of an individual cancer cell, for example, suggested it was doing something unusual.

“We’ll give people the capability to release that cell and study it,” he said. “We don’t have a device like that at present.”

Congratulations Justin, Moinul, Simone, Ying, Roya, Leila and Vinicius