In this work, an intermediate layer of Mo is pre-deposited on the flexible Mo foil before the deposition of Cu₂ZnSnS₄ (CZTS) thin film to optimise the characteristics of the flexible CZTS thin film solar cell (TFSC). It is confirmed that the pre-deposition of the Mo layer leads to the improvement in the degree of the interface matching between the back electrode and the CZTS thin film which is always regarded as the main recombination centres of the carriers in the solar cell. By employing a Mo interlayer between the Mo foil and CZTS layer, the conversion efficiency of the as-fabricated (Mo foil/Mo/CZTS/CdS/i-ZnO/AZO/Ni/Al) solar cell is further increased from 1.27 to 1.46%. Meanwhile, the traditional structure (soda-lime glass/Mo/CZTS/CdS/i-ZnO/AZO/Ni/Al) CZTS TFSC acted as a matched group which is also prepared and obtained a conversion efficiency of 1.58%. This work demonstrates for the first time the effects of Mo intermediate layers in the flexible CZTS TFSCs.

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Modification of back electrode structure by a Mo intermediate layer for flexible CZTS thin film solar cells

References

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