The research opens the door to the possibility of weaving together solar-cell silicon wires to create flexible, curved or twisted solar fabrics.
The team's new findings build on earlier work addressing the challenge of merging optical fibers with electronic chips, silicon-based integrated circuits that serve as the building blocks for most semiconductor electronic devices such as solar cells, computers and cellphones. Rather than merge a flat chip with a round optical fiber, the team found a way to build a new kind of optical fiber, with its own integrated electronic component, thereby bypassing the need to integrate fiber-optics with chips. To do this, they used high-pressure chemistry techniques to deposit semiconducting materials directly, layer by layer, into tiny holes in optical fibers.
A cross-sectional image of the new silicon-based optical fiber. Shown are layers, labeled n+, i and p+, that have been deposited inside the pore of the fiber: Source - Penn State University
Now, in their new research, the team members have used the same high-pressure chemistry techniques to make a fiber out of crystalline silicon semiconductor materials that can function as a solar cell, a photovoltaic device that can generate electrical power by converting solar radiation into direct-current electricity. "Our goal is to extend high-performance electronic and solar-cell function to longer lengths and to more flexible forms. We already have made meters-long fibers but, in principle, our team's new method could be used to create bendable silicon solar-cell fibers of over 10 meters in length," Badding said. "Long, fiber-based solar cells give us the potential to do something we couldn't really do before: We can take the silicon fibers and weave them together into a fabric with a wide range of applications such as power generation, battery charging, chemical sensing and biomedical devices."
Woven, fiber-based solar cells would be lightweight, flexible configurations that are portable, foldable and even wearable." This material could then be connected to