A photovoltaic cell includes a substrate layer, an anode layer on the substrate layer, an active layer on the anode layer, and a cathode layer on the active layer, wherein the active layer comprises a plurality of disparately sized n-type and p-type nano-particles of different semiconductor materials randomly distributed in a conductive polymer blend. The n-type nano-particles can include either ZnO or In2O3 nano-particles, and the p-type nano-particles can include either NiO or La2O3 nano-particles. The conductive polymer blend can include P3HT. The bandgaps of the nano-particles have corresponding energies ranging from the near ultraviolet to the far infrared.