(Phys.org)—Controlling "mixing" between acceptor and donor
layers, or domains, in polymer-based solar cells could increase
their efficiency, according to a team of researchers that
included physicists from North Carolina State University. Their
findings shed light on the inner workings of these solar cells,
and could lead to further improvements in efficiency. Polymer-
based solar cells consist of two domains, known as the acceptor
and the donor layers. Excitons, the energy particles created by
solar cells, must be able to travel quickly to the interface of
the donor and acceptor domains in order to be harnessed as an
energy source. Researchers had believed that keeping the donor
and acceptor layers as pure as possible was the best way to
ensure that the excitons could travel unimpeded, so that solar
cells could capture the maximum amount of energy. NC State
physicist Harald Ade and his group worked with teams of
scientists from the United Kingdom, Australia and China to
examine the physical structure and impr