Plastic Fantastic: Next-gen electronics

Jess Wade has been in the news for her efforts to call attention to the diverse work of women in STEM. You can hardly find an article about diversity in STEM that doesn't include an interview or quote from Jess—while she was in San Diego attending Optics + Photonics she had interviews with a news outlet in Brazil and a 3 a.m. phone call with the BBC.

But what most of the press glosses over is that Jess is a physicist who is doing some fascinating science in its own right. She's working on semiconducting light-emitting polymers for OLEDs.

Although polymers shouldn't semiconduct-they're plastic, after all-her team is working with a carbon-based polymer with a special type of bond (single-double-single-double) that lets them act like semiconductors. They have all the good properties of plastics-they can be dissolved in solvents, printed at room temperature, and they're cheap-and they also have the electronic properties of semiconductors, like silicon.

Wade is trying to find a combination of these light-emitting polymers with small twisted (chiral) dopants that can induce a strong polarization effect in the polymers. And the potential applications are intriguing.

Whereas OLEDs are most well known as displays for TVs and cell phones, Wade points out that the commercialization of OLED displays shows that the technology has matured, and basic research is no longer needed in that area. What's really exciting is taking this research to biosensors.

It may be possible to combine these polymer OLEDs with other organic devices, like a photodetector, to make a biosensor that's thin, flexible, and disposable.

"Chiral molecular recognition is enantioselective and incredibly powerful. It can be used to identify chiral biomolecules in sweat or blood, differentiate pharmaceuticals and separate stereoisomers in the chemical industry. We're beginning to explore how our materials could be developed for a range of sensing applications," explains Wade.

Another potential application is water splitting. By covering a ferromagnetic electrode with a chiral material, and photoexciting it by electrolysis, it could be possible to suppress the formation of hydrogen peroxide, which competes with the release of hydrogen that is useful for fuel. "Powering hydrogen fuel cells by splitting water using solar power is a very trendy area of research at the moment," said Wade.

According to Wade, chirality is the one area of science that combines physics, chemistry, and biology perfectly. She says, "Physicists find it so fascinating, chemists enjoy the synthesis, and basically all of biology relies on chiral structures. Everything is left- or right- handed. And we're just learning the processing about how to do it."

Watch her presentation at Optics + Photonics 2018 on the SPIE Digital Library: doi.org/10.1117/12.2321171. Keep up with Wade's outreach and research by following @JessWade on Twitter.