Improvement of kesterite solar cell performance by solution synthesized MoO3 interfacial layer

Abstract

In this study, an ultra-thin MoO3 layer synthesized by a solution-based technique is introduced as a promising interfacial layer to improve the performance of kesterite Cu2ZnSnSe4 (CZTSe) solar cell. Solar cells with 10nm of MoO3 between Mo rear contact and CZTSe had larger minority carrier life time and open-circuit voltage compared to the reference solar cells. Temperature dependent current density-voltage measurement indicated that the activation energy (E-A) of the main recombination is higher (approximate to 837 meV) in solar cells with MoO3 layer, as compared to conventional solar cells where E-A approximate to 770meV, indicating reduced interface recombination. A best efficiency of 7.1% was achieved for a SLG/Mo/MoO3/CZTSe/CdS/TCO solar cell compared to the reference solar cell SLG/Mo/CZTSe/CdS/TCO for which 5.9% efficiency was achieved.