Quantum Dots For Untapped Energy
Posted by evolvingwheel on January 30, 2007
Recent developments in nanoparticles have emerged possibilities that open new horizons in alternative sources of energy. One of them is solar energy and photovoltaic (PV) cells. Ted Sergent and his colleagues at the University of Toronto have invented a plastic infrared solar cell that is capable of tuning the bandgap in a semiconductor material. The team developed a semiconducting plastic (a polymer) where the size of the nanocrystals can be controlled to optimize the efficiency of the solar cell.
The high cost of fabrication and limited efficiency in converting solar energy to electricity have handicapped the first and second generations of solar cells. The yield versus the investment has limited the growth of this alternative energy source among average consumers globally. However, new developments in nanocrystals and methods of fabricating polymer plastics with quantum dots have created opportunities to implement a technology that promises cheap implementation and extremely high efficiency.
The first advantage of quantum dots is their tunable bandgap. By controlling the size of the nanocrystals one can generate high voltage with regular incident sunlight. Quantum dots can improve the efficiency of solar cell by extending the band gap and also by generating more charges from a single photon. Secondly, in contrast to traditional semiconductor materials that are rigid, quantum dots can be molded into different shapes and forms and hence can be implemented as sheets or films – an extremely attractive proposition for commercial impementation. Finally, the ability of the polymer to absorb light in the non-visible range opens a sudden and unexpected realm. Nearly half of the approximately 1000Wm3 of the intensity of sunlight is in the infrared zone. Infrared photovoltaic cells can even capture radiation from heat sources like industrial facilities. This implicates an enormous potential. The devices can be installed in thousands of industrial manufacturing lines to abosrb the energy and convert to electricity, thereby leading to an opportunity of delivering power from non-power generation sectors! [Click here for article]
And the business opportunities? 🙂