High efficiency solid-state photovoltaic device due to inhibition of interface charge recombination

The performance of solid-state dye-sensitized solar cells based on spiro-Me OTAD was considerably improved by controlling charge recombination across t he interface of the heterojunction. This was achieved by blending the hole conductor matrix with a combination of 4-tert-butylpyridine (tBP) and Li[CF 3SO2](2)N. Open circuit voltages U-oc over 900 mV and short circuit current s I-sc up to 5.1 mA were obtained, yielding an overall efficiency of 2.56% at AM1.5 illumination. These values have been fully confirmed at the Nation al Renewable Energy Laboratories for a device with an active area of 1.07 c m(2), signifying a dramatic improvement compared to previously reported val ues for a similar device. (C) 2001 American Institute of Physics.