Photovoltaic performance and stability of CdTe/polymeric hybrid solar cells using a C60 buffer layer

The influence of C60 as a buffer layer on photovoltaic performance and stability of bulk hetero-junction solar cells using a photoactive layer of CdTe nanocrystals and poly(p-phenylenevinylene) derivative has been investigated. The incident photon-to-current conversion efficiency of the sealed-cells with a C60 buffer layer was about 70% of that of solar cells using a buffer layer of LiF. The introduction of C60 buffer layer gave an improvement in the stability for a light-harvesting test. In a long-term thermal stability test, there was no difference between the solar cells using C60 and LiF. An impedance analysis suggested that the degradation of the performance in the stability tests was associated with a decrease in the conductance of the cells.