Performance of hybrid polymer solar cells based on graphene/CuInS2

Abstract

Abstract: Solar cells are fabricated by blending the reduced graphene oxide-CuInS2 quantum dots hybrid (rGO/CuInS2-QDS) with poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene) (MEH-PPV), producing MEH-PPV/rGO-CuInS2 devices. We studied the MEH-PPV/rGO-CuInS2 devices with dynamic method to reveal the features in charge transport dynamics in the devices. The results show that the MEH-PPV/rGO-CuInS2 devices exhibit significantly increased electron transit time and electron lifetime, which are attributed to the surface electron trapping on the CuInS2-QDS and the barrier effect of CuInS2-QDS on the rGO sheets by increasing the spatial e?h separation, respectively. Moreover, it is demonstrated that the increased short-circuit current in the MEH-PPV/rGO-CuInS2 devices is mainly related to the increased polymer exciton dissociation and reduced charge recombination, while the open-circuit voltage is determined by the energy difference between the highest occupied molecular orbital level of MEH-PPV and the work-function of rGO but significantly correlates with the concentration of the electrons in rGO.

Key words: CuInS2

References

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