Controlled emission/absorption beats the Shockley-Queisser limit

Not only is the group interested in high conversion efficiencies,
but also in widening the range of functionalities of
photovoltaics, such as the integration of PV with small
consumer electronics or large building components. In
particular, the characteristic interaction between light and
sub-wavelength semiconductors results in optical responses
uncorrelated to their bulk counterparts. Depending on the
nanostructure morphology and collective arrangement, the
photovoltaic active material can be tuned in color and/or
transparency. This modulation in turn affects the PV
performance not only by the absolute number of photons that
are absorbed, but also through the spectral and angular
distribution of absorption/emission. As a result, larger open
circuit potentials can be achieved than in compositionally
equivalent bulk semiconductors.