Researchers are using paper to devise an easier, more environmentally-friendly way of harnessing the power of the sun.

UT chemical engineers, biologists and artists recently collaborated to develop a method of creating solar cells on paper. These paper solar cells provide a foldable, more environment-friendly method of collecting solar energy compared to traditional photovoltaics, which are materials that convert sunlight into electricity. Potential uses for this new product include body-integrated electronics or small sensors. The researchers published their findings in Energy Letters on Jan. 31.

Modern photovoltaics are typically composed of silicon and glass panels, making them bulky and difficult to transport. Paper solar cells, on the other hand, are biodegradable, flexible and cheap to make. James Sham, researcher in UT’s art and art history department and co-author of the paper, said that his inspiration for solar paper came from observing the Brazilian government bringing solar panels into indigenous
forest communities.

“The more panels they bring in, the more they have to deforest,” Sham said. “In my mind this was a conflict between two ways of life. I started to imagine whether it would be possible that it did not compete with nature. I started thinking about building solar panels like leaves — a disperse amount of leaves across a wide acreage.”

Sham worked with R. Malcolm Brown, molecular biosciences professor and co-author of the paper, to cultivate bacteria for use in the paper solar cells. Sham said paper made by these bacteria have a unique texture that allows them to tightly bind to photovoltaic devices.

“This paper doesn’t come from trees or plant matter — it’s cultivated from bacteria,” Sham said. “Theoretically, all we need is a wet lab set up so we can manufacture this on site. In some future universe, when we’re starting to colonize Mars, you can’t just bring a whole bunch of solar panels from Earth to Mars.” 

Vikas Reddy Voggu, chemical engineering graduate student and first author of the paper, said that in addition to being produced sustainably, the paper solar cells have comparable production rates to those of solar panels in space. He added that the paper solar cells are also flexible and easy to transport.

“These solar cells can be folded like origami — once you fold them, the transport costs can be reduced,” Reddy said. 

Reddy added that the devices are compatible for sticking directly onto the skin, raising the possibility for their use on our bodies in everyday life. According to the study, the paper solar cells can easily work with other electronics, such as in small sensors used in
field work.

The paper solar cells project was part of the Rapid Design Pivot Program, in which artists work with scientists in a laboratory setting in order to facilitate innovation. Sham and Brian Korgel, UT chemical engineering professor and co-author of the paper, designed the program together.

Sham said that they designed the program so that artists could help researchers approach scientific problems in a nonlinear way and create new solutions.

“Most artists I know will intentionally try to do something nobody else will do in order to get a result that is miraculous or new in some way,” Sham said. “When we brought artists in and gave them freedom to attack ideas they normally wouldn’t, (the paper solar cells) are the kinds of things that happen.”