The light conversion efficiency of a solar cell (10) is enhanced by using an optical downshifting layer (30) in cooperation with a photovoltaic material (22). The optical downshifting layer converts photons (50) having wavelengths in a supplemental light absorption spectrum into photons (52) having a wavelength in the primary light absorption spectrum of the photovoltaic material. The cost effectiveness and efficiency of solar cells platforms (20) can be increased by relaxing the range of the primary light absorption spectrum of the photovoltaic material. The optical downshifting layer can be applied as a low cost solution processed film composed of highly absorbing and emissive quantum dot heterostructure nanomaterial embedded in an inert matrix to improve the short wavelength response of the photovoltaic material. The enhanced efficiency provided by the optical downshifting layer permits advantageous modifications to the solar cell platform that enhances its efficiency as well.