Modification of back electrode structure by a Mo intermediate layer for flexible CZTS thin film solar cells
- Author(s): Bo Long 1 ; Shuying Cheng 2 ; Chuang Yue 3 ; Limei Dong 2
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View affiliations
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Affiliations:
1:
College of Mechanical and Electrical Engineering , Fujian Agriculture and Forestry University , Fuzhou , Fujian Province , CN 350002 , People's Republic of China ;
2: College of Physics and Information Engineering, and Institute of Micro-Nano Devices & Solar Cells , Fuzhou University , Fuzhou , Fujian Province , CN 350108 , People's Republic of China ;
3: Department of Energy Engineering , Hanyang University , Seoul , CN 04763 , South Korea
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Affiliations:
1:
College of Mechanical and Electrical Engineering , Fujian Agriculture and Forestry University , Fuzhou , Fujian Province , CN 350002 , People's Republic of China ;
- Source:
Volume 13, Issue 2,
February
2018,
p.
237 – 242
DOI: 10.1049/mnl.2017.0471 , Online ISSN 1750-0443
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.
Inspec keywords: semiconductor thin films; wide band gap semiconductors; zinc compounds; aluminium; nickel; solar cells; tin compounds; copper compounds; electrochemical electrodes; molybdenum; II-VI semiconductors; cadmium compounds
Other keywords: Mo-Cu2ZnSnS4-CdS-ZnO-ZnO:Al-Ni-Al; flexible thin film solar cells; soda-lime glass; intermediate layer; interface matching; conversion efficiency; back electrode structure; carrier recombination centres
Subjects: Electrochemistry and electrophoresis; Solar cells and arrays; Photoelectric conversion; solar cells and arrays
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