New Technology For Cheaper More Efficient Solar Cells

Professor of chemical engineering Stacey Bent first became interested in a new kind of solar technology two years ago. These solar cells used tiny particles of semiconductors called "quantum dots."

Quantum dot solar cells (<=see Google...) are cheaper to produce than traditional ones, as they can be made using simple chemical reactions. But despite their promise, they lagged well behind existing solar cells in efficiency.

But solar cells made of a single material have a maximum efficiency of about 31 percent, a limitation of the fixed energy level they can absorb.

Quantum dot solar cells do not share this limitation and can in theory be far more efficient. The energy levels of electrons in quantum dot semiconductors depends on their size - the smaller the quantum dot, the larger the energy needed to excite electrons to the next level.

So quantum dots can be tuned to absorb a certain wavelength of light just by changing their size. And they can be used to build more complex solar cells that have more than one size of quantum dot, allowing them to absorb multiple wavelengths of light.

Source=> New Technology For Cheaper More Efficient Solar Cells