<i>V</i><sub>oc</sub> deficit in kesterite solar cells

Yuancai Gong; Hao Xin; Liming Ding

doi:10.1088/1674-4926/42/10/100201

J. Semicond. > 2021, Volume 42 > Issue 10 > 100201

RESEARCH HIGHLIGHTS

V_oc deficit in kesterite solar cells

Yuancai Gong¹, Hao Xin^1, and Liming Ding^2,

+ Author Affiliations

1. Key Laboratory for Organic Electronics and Information Displays, Institute of Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing 210023, China
2. Center for Excellence in Nanoscience (CAS), Key Laboratory of Nanosystem and Hierarchical Fabrication (CAS), National Center for Nanoscience and Technology, Beijing 100190, China

Author Bio:

Yuancai Gong is a PhD candidate in School of Materials Science and Engineering, Nanjing University of Posts & Telecommunications, under the supervision of Prof. Hao Xin. His research focuses on kesterite solar cells.

Hao Xin is a professor in School of Materials Science and Engineering, Nanjing University of Posts & Telecommunications. She received her PhD from Peking University in 2003. She was a JST-CREST researcher at NIMS and a JSPS fellow at JAIST from 2003 to 2006. Then she worked in Department of Chemical Engineering at the University of Washington until 2012. Her current research focuses on solution processed solar cells (CZTS, CIGS and perovskite).

Liming Ding got his PhD from University of Science and Technology of China (was a joint student at Changchun Institute of Applied Chemistry, CAS). He started his research on OSCs and PLEDs in Olle Inganäs Lab in 1998. Later on, he worked at National Center for Polymer Research, Wright-Patterson Air Force Base and Argonne National Lab (USA). He joined Konarka as a Senior Scientist in 2008. In 2010, he joined National Center for Nanoscience and Technology as a full professor. His research focuses on innovative materials and devices. He is RSC Fellow, the nominator for Xplorer Prize, and the Associate Editors for Science Bulletin and Journal of Semiconductors.

Corresponding author: Hao Xin, iamhxin@njupt.edu.cn; Liming Ding, ding@nanoctr.cn

DOI: 10.1088/1674-4926/42/10/100201

References

[1]	Wang W, Winkler M T, Gunawan O, et al. Device characteristics of CZTSSe thin-film solar cells with 12.6% efficiency. Adv Energy Mater, 2014, 4, 1301465 doi: 10.1002/aenm.201301465
[2]	Son D H, Kim S H, Kim S Y, et al. Effect of solid-H₂S gas reactions on CZTSSe thin film growth and photovoltaic properties of a 12.62% efficiency device. J Mater Chem A, 2019, 7, 25279 doi: 10.1039/C9TA08310C
[3]	Nakamura M, Yamaguchi K, Kimoto Y, et al. Cd-free Cu(In,Ga)(Se,S)₂ thin-film solar cell with record efficiency of 23.35%. IEEE J Photovolt, 2019, 9, 1863 doi: 10.1109/JPHOTOV.2019.2937218
[4]	Fonoll-Rubio R, Andrade-Arvizu J, Blanco-Portals J, et al. Insights into interface and bulk defects in a high efficiency kesterite-based device. Energy Environ Sci, 2021, 14, 507 doi: 10.1039/D0EE02004D
[5]	Chen S, Walsh A, Gong X G, et al. Classification of lattice defects in the kesterite Cu₂ZnSnS₄ and Cu₂ZnSnSe₄ earth-abundant solar cell absorbers. Adv Mater, 2013, 25, 1522 doi: 10.1002/adma.201203146
[6]	Giraldo S, Jehl Z, Placidi M, et al. Progress and perspectives of thin film kesterite photovoltaic technology: A critical review. Adv Mater, 2019, 31, 1806692 doi: 10.1002/adma.201806692
[7]	Tian Q, Liu S. Defect suppression in multinary chalcogenide photovoltaic materials derived from kesterite: progress and outlook. J Mater Chem A, 2020, 8, 24920 doi: 10.1039/D0TA08202C
[8]	Kim S, Park J S, Walsh A. Identification of killer defects in kesterite thin-film solar cells. ACS Energy Lett, 2018, 3, 496 doi: 10.1021/acsenergylett.7b01313
[9]	Rey G, Larramona G, Bourdais S, et al. On the origin of band-tails in kesterite. Sol Energy Mater Sol Cells, 2018, 179, 142 doi: 10.1016/j.solmat.2017.11.005
[10]	Crovetto A, Kim S, Fischer M, et al. Assessing the defect tolerance of kesterite-inspired solar absorbers. Energy Environ Sci, 2020, 13, 3489 doi: 10.1039/D0EE02177F
[11]	Rey G, Redinger A, Sendler J, et al. The band gap of Cu₂ZnSnSe₄: Effect of order-disorder. Appl Phys Lett, 2014, 105, 112106 doi: 10.1063/1.4896315
[12]	Bourdais S, Chone C, Delatouche B, et al. Is the Cu/Zn disorder the main culprit for the voltage deficit in kesterite solar cells. Adv Energy Mater, 2016, 6, 1502276 doi: 10.1002/aenm.201502276
[13]	Ma S, Li H, Hong J, et al. Origin of band-tail and deep-donor states in Cu₂ZnSnS₄ solar cells and their suppression through Sn-poor composition. J Phys Chem Lett, 2019, 10, 7929 doi: 10.1021/acs.jpclett.9b03227
[14]	Gong Y, Zhang Y, Jedlicka E, et al. Sn⁴⁺ precursor enables 12.4% efficient kesterite solar cell from DMSO solution with open circuit voltage deficit below 0.30 V. Sci China Mater, 2021, 64, 52 doi: 10.1007/s40843-020-1408-x
[15]	Gong Y, Zhang Y, Zhu Q, et al. Identify the origin of the V_oc deficit of kesterite solar cells from the two grain growth mechanisms induced by Sn²⁺ and Sn⁴⁺ precursors in DMSO solution. Energy Environ Sci, 2021, 14, 2369 doi: 10.1039/D0EE03702H

Fig. 1. (Color online) (a) “Order–disorder” transition of kesterite upon thermal annealing. Reproduced with permission^[11], Copyright 2014, AIP Publishing LLC. (b) J–V curves for CZTSSe devices with PD (partially disordered) and PO (partially ordered) absorber. (c) Extraction of the bandgaps for CZTSSe absorbers in (b) from the absorption spectra. Reproduced with permission^[12], Copyright 2016, Wiley-VCH. (d) Illustration of the band-tail and donor defect states for CZTS absorbers made under Sn-rich and Sn-poor conditions. Reproduced with permission^[13], Copyright 2019, American Chemical Society.

DownLoad: Full-Size Img PowerPoint

Fig. 2. (Color online) SEM images at different stage of selenization clearly show (a) grain growth of Sn²⁺ film with a multi-phase conversion and (b) grain growth of Sn⁴⁺ film with a uniform direct transformation. (c) J–V curves, (d) EQE spectra, (e) bandgap fluctuation (σ_g), (f) electrostatic potential fluctuation (γ_opt), and (g) Urbach energy (E_U) for CZTSSe devices made from Sn²⁺ and Sn⁴⁺ solutions with and w/o thermal annealing. (h) Defect profiles measured by capacitance–voltage (C–V) and drive-level capacitance profiling (DLCP) for thermally-annealed Sn²⁺ and Sn⁴⁺ devices. Reproduced with permission^[15], Copyright 2021, Royal Society of Chemistry.

DownLoad: Full-Size Img PowerPoint

[1]	Wang W, Winkler M T, Gunawan O, et al. Device characteristics of CZTSSe thin-film solar cells with 12.6% efficiency. Adv Energy Mater, 2014, 4, 1301465 doi: 10.1002/aenm.201301465
[2]	Son D H, Kim S H, Kim S Y, et al. Effect of solid-H₂S gas reactions on CZTSSe thin film growth and photovoltaic properties of a 12.62% efficiency device. J Mater Chem A, 2019, 7, 25279 doi: 10.1039/C9TA08310C
[3]	Nakamura M, Yamaguchi K, Kimoto Y, et al. Cd-free Cu(In,Ga)(Se,S)₂ thin-film solar cell with record efficiency of 23.35%. IEEE J Photovolt, 2019, 9, 1863 doi: 10.1109/JPHOTOV.2019.2937218
[4]	Fonoll-Rubio R, Andrade-Arvizu J, Blanco-Portals J, et al. Insights into interface and bulk defects in a high efficiency kesterite-based device. Energy Environ Sci, 2021, 14, 507 doi: 10.1039/D0EE02004D
[5]	Chen S, Walsh A, Gong X G, et al. Classification of lattice defects in the kesterite Cu₂ZnSnS₄ and Cu₂ZnSnSe₄ earth-abundant solar cell absorbers. Adv Mater, 2013, 25, 1522 doi: 10.1002/adma.201203146
[6]	Giraldo S, Jehl Z, Placidi M, et al. Progress and perspectives of thin film kesterite photovoltaic technology: A critical review. Adv Mater, 2019, 31, 1806692 doi: 10.1002/adma.201806692
[7]	Tian Q, Liu S. Defect suppression in multinary chalcogenide photovoltaic materials derived from kesterite: progress and outlook. J Mater Chem A, 2020, 8, 24920 doi: 10.1039/D0TA08202C
[8]	Kim S, Park J S, Walsh A. Identification of killer defects in kesterite thin-film solar cells. ACS Energy Lett, 2018, 3, 496 doi: 10.1021/acsenergylett.7b01313
[9]	Rey G, Larramona G, Bourdais S, et al. On the origin of band-tails in kesterite. Sol Energy Mater Sol Cells, 2018, 179, 142 doi: 10.1016/j.solmat.2017.11.005
[10]	Crovetto A, Kim S, Fischer M, et al. Assessing the defect tolerance of kesterite-inspired solar absorbers. Energy Environ Sci, 2020, 13, 3489 doi: 10.1039/D0EE02177F
[11]	Rey G, Redinger A, Sendler J, et al. The band gap of Cu₂ZnSnSe₄: Effect of order-disorder. Appl Phys Lett, 2014, 105, 112106 doi: 10.1063/1.4896315
[12]	Bourdais S, Chone C, Delatouche B, et al. Is the Cu/Zn disorder the main culprit for the voltage deficit in kesterite solar cells. Adv Energy Mater, 2016, 6, 1502276 doi: 10.1002/aenm.201502276
[13]	Ma S, Li H, Hong J, et al. Origin of band-tail and deep-donor states in Cu₂ZnSnS₄ solar cells and their suppression through Sn-poor composition. J Phys Chem Lett, 2019, 10, 7929 doi: 10.1021/acs.jpclett.9b03227
[14]	Gong Y, Zhang Y, Jedlicka E, et al. Sn⁴⁺ precursor enables 12.4% efficient kesterite solar cell from DMSO solution with open circuit voltage deficit below 0.30 V. Sci China Mater, 2021, 64, 52 doi: 10.1007/s40843-020-1408-x
[15]	Gong Y, Zhang Y, Zhu Q, et al. Identify the origin of the V_oc deficit of kesterite solar cells from the two grain growth mechanisms induced by Sn²⁺ and Sn⁴⁺ precursors in DMSO solution. Energy Environ Sci, 2021, 14, 2369 doi: 10.1039/D0EE03702H