Nearly doubling the efficiency of a breakthrough
photovoltaic cell they created last year, UCLA researchers have developed a
two-layer, see-through solar film that could be placed on windows, sunroofs,
smartphone displays and other surfaces to harvest energy from the sun.
The new device is composed of two thin polymer solar cells
that collect sunlight and convert it to power. It's more efficient than
previous devices, the researchers say, because its two cells absorb more light
than single-layer solar devices, because it uses light from a wider portion of
the solar spectrum, and because it incorporates a layer of novel materials
between the two cells to reduce energy loss.