Canadian scientists have developed a new technology that can significantly improve the efficiency of solar cells. This technology can increase the solar conversion efficiency by 35% in the near-infrared spectrum region. The overall conversion efficiency (full spectrum) is thus increased by 11%, thereby making quantum dot photovoltaic Become an excellent candidate to replace the existing solar cell technology. Related papers were published in the latest issue of "Nano Letters".
Quantum dot photovoltaic cells can provide low-cost, large-area solar power, but the device is not efficient in the infrared section of the solar spectrum, and the infrared section occupies half of the solar energy reaching the earth. Ted Sargent, a professor of engineering at the University of Toronto in Canada, and his research group proposed that plasma nanoparticles that provide spectrum tuning and solution treatment can provide unprecedented control over the propagation and absorption of light.
Colloidal quantum dots have two major advantages. The first is cheaper, because they reduce the cost of generating electricity per watt, but the more important advantage is that simply changing the size of the quantum dots can change the absorption spectrum. The size is easy to change and tunability is a property of plasma materials: by changing the size of plasma particles, researchers can overlap the absorption and scattering spectra of these two important nanoparticles.
Sargent's research team has improved the efficiency of solar cells by directly embedding gold nanoshells in quantum dot absorption films. They will next look to use cheaper metals to achieve the same goal. Paul Weiss, director of the Institute of Nanosystems at the University of California, believes that the importance of this research is to demonstrate the potential to improve the efficiency of solar cells by adjusting the characteristics of nanoparticles.