Spray-On Solar-Power Cells Are A True Breakthrough
Not only are panels expensive to install, they capture only the visible portion
of the sun's rays so they work only on sunny days. Ted's focus is the infrared
portion of the sun's rays which accounts for more than half of all solar energy.
What's more, infrared energy is available to us even in cloudy weather.
A quantum dot is a semiconductor nanostructure that confines the motion of
conduction band electrons, valence band holes, or excitons (bound pairs of conduction
band electrons and valence band holes) in all three spatial directions. The
confinement can be due to electrostatic potentials (generated by external electrodes,
doping, strain, impurities), the presence of an interface between different
semiconductor materials (e.g. in core-shell nanocrystal systems), the presence
of the semiconductor surface (e.g. semiconductor nanocrystal), or a combination
of these. A quantum dot has a discrete quantized energy spectrum. The corresponding
wave functions are spatially localized within the quantum dot, but extend over
many periods of the crystal lattice. A quantum dot contains a small finite number
(of the order of 1-100) of conduction band electrons, valence band holes, or
excitons, i.e., a finite number of elementary electric charges.
Run time 3.05 mins