Improving Ultraviolet Responses in Cu<sub>2</sub>ZnSn(S,Se)<sub>4</sub> Thin-Film Solar Cells Using Quantum Dot-Based Luminescent Down-Shifting Layer
Woo-Lim Jeong,
Junsung Jang,
Jihun Kim,
Soo-Kyung Joo,
Mun-Do Park,
Hoe-Min Kwak,
Jaeyoung Baik,
Hyeong-Jin Kim,
Jin Hyeok Kim,
Dong-Seon Lee
Affiliations
Woo-Lim Jeong
School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Junsung Jang
Optoelectronic Convergence Research Center, Department of Materials Science and Engieering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Korea
Jihun Kim
School of Integrated Technology, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Soo-Kyung Joo
College of Basic and General Education, Dongshin University, 67 Dongshinedae-gil, Naju-si 58246, Jeollanam-do, Korea
Mun-Do Park
School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Hoe-Min Kwak
School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Jaeyoung Baik
School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Hyeong-Jin Kim
School of Integrated Technology, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Jin Hyeok Kim
Optoelectronic Convergence Research Center, Department of Materials Science and Engieering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Korea
Dong-Seon Lee
School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
Quantum dot (QD)-based luminescent down-shifting (LDS) layers were deposited on Cu2ZnSn(S,Se)4 (CZTSSe) solar cells via the drop-casting method. The LDS layers can easily widen the narrow absorption wavelength regions of single-junction solar cells and enable improvement of the short-circuit current. The optical properties of LDS layers deposited on glass and containing different QD contents were analyzed based on their transmittance, reflectance, and absorbance. The absorber films to be used in the CZTSSe solar cells were determined by X-ray diffraction measurements and Raman spectroscopy to determine their crystal structures and secondary phases, respectively. The completed CZTSSe solar cells with LDS layers showed increased ultraviolet responses of up to 25% because of wavelength conversion by the QDs. In addition, the impact of the capping layer, which was formed to protect the QDs from oxygen and moisture, on the solar cell performance was analyzed. Thus, a maximal conversion efficiency of 7.3% was achieved with the 1.0 mL QD condition; furthermore, to the best of our knowledge, this is the first time that LDS layers have been experimentally demonstrated for CZTSSe solar cells.
