If Xiaolin Zheng would have her way, producing solar energy would be as easy as applying a sticker. Zheng is not an ordinary person. She is one of National Geographic’s Emerging Explorers of 2014. This program is designed to honour the visionaries of tomorrow or those who are willing to make a difference and inspire people to care for the earth, with their new inventions.
Zheng has developed an extremely thin and very flexible solar panel that can be attached to a surface just like pasting a sticker. These pizza-like solar cells could make a big difference in the harvesting of solar energy in difficult situations.
Stick-on solar panels groundbreaking technology
What induced Zheng to develop her ground-breaking work was an off-hand comment from her father. “One day my father mentioned how great it would be if a building’s entire surface could be used for solar power, not just the roof, but also walls and windows,” recounted Zheng.
“In China, the rooftops of many buildings are packed with solar energy devices,” added Zheng.
Her research team at Stanford University had developed the pizza-like solar cells that may someday make the wish of his father come true. These are solar cells that are thin, flexible and adhesive. They can actually be considered as solar stickers that could provide power to almost anything, from buildings to airplanes.
Stick-on solar panels solving energy harvesting issues
“By making the stick-on solar panels extremely thin and flexible, they can be used in all kinds of new ways,” Zheng explained, who is also an associate professor at Stanford and a recipient of the U.S. Presidential Early Career Award for Scientists and Engineers.
“I hope our discovery of the stick-on solar panels will dramatically expand the affordable, practical, widespread application of solar power,” she added.
In 2010, about ten years after his father made that comment, Zheng happened to read a research paper that rekindled the idea in his brain. The paper discussed an experiment where nanomaterial grapheme was grown on a layer of nickel on top of a silicon wafer.
When they submerged the wafer in water, the nickel separated from the surface, together with the grapheme. “It sounded unbelievable, like a magic trick,” recalled Zheng,
Stick-on solar panels to aids affordability & practicality of widespread application
“But they had achieved very reliable results,” she added. She wondered, could it be possible to use the same principle to create a thinner, more flexible solar cell that could peel off, attach to adhesive, and stick to virtually any surface?
“Our new stick-on solar panels let us treat the solar cells like a pizza,” explained Zheng. “When you bake pizza, you use a metal pan that can tolerate high temperatures. But when it’s time to distribute the pizza economically, it’s placed in a paper box,” she added.
Zheng worked with her students and developed solar cells on silicone or glass surfaces, just like conventional methods. But she inserted a metallic layer between the cell and the surface.
After several attempts, the team of Zheng was able to create active stick-on solar panels that were only a few microns thick, around one-tenth of a plastic wrap. “It’s extremely flexible, so it can be attached to any surface—the back of a mobile phone, a skylight, a wall, a curved column,” she enthused.
