A new kind of solar-sensitive nanoparticles could create flexible and efficient solar cells, possible making the technology available to consumers on a huge scale, Canadian researchers say.
The newly designed nanoparticle, dubbed a "colloidal quantum dot," makes use of two kinds of semiconductors, of which one has an unfortunate tendency to break down when it's exposed to air, losing its electrons and its ability to generate electricity, they said.
University of Toronto researchers say they've solved that dilemma by creating a nanoparticle "dot" that does will bind with oxygen during exposure to air.
Such quantum dots, being much more stable, could lead to solar cells that are more flexible and cheaper to manufacture to use in a number of different applications, they said.
"Colloidal quantum dots (CQDs) offer promise in flexible electronics, light sensing and energy conversion," the researchers wrote in the journal Nature Materials.
By boosting light absorption, they could also be used in other technical applications and optoelectrical devices combing electricity and light such as infrared lasers, gas sensors, or infrared light-emitting diodes, they said.
They could also lead to advances in "weather satellites, remote controllers, satellite communication, or pollution detectors," they wrote.
"This is a material innovation, that's the first part, and with this new material we can build new device structures," post-doctoral researcher Zhijun Ning said.
Once the technology is refined, the researchers said, the quantum dots could even be mixed with inks for printed surfaces, into paint, or applied to flexible substrates such as roof shingles to create solar power for millions around the world at an affordable cost.
The new quantum dot material has achieved conversion efficiently for solar power of up to eight percent, the researchers said, among the best results from similar technology reported to date.
"The field of colloidal quantum dot photovoltaics requires continued improvement in absolute performance, or power conversion efficiency," says Toronto researcher Ted Sargent, in the university's Edward S. Rogers Sr. Department of Electrical & Compute Engineering. "The field has moved fast, and keeps moving fast, but we need to work toward bringing performance to commercially compelling levels."
Participating in the Toronto research were scientists from Dalhousie University in Nova Scotia, King Abdulla University of Science and Technology in Saudi Arabia and Huazhong University of Science and Technology in China.
