Preparation of hysteresis-free flexible perovskite solar cells via interfacial modification

doi:10.1016/j.jmst.2020.05.029

Abstract

Abstract:

In recent years, flexible perovskite solar cells have received extensive attention and rapid development due to their advantages of lightweight, portability, wearability and applications in near-space. However, due to the limitations of their preparation process and other factors, high-efficiency and large-area flexible perovskite solar cells still have a lot of room for development. In our work, a flexible perovskite solar cell (PEN/ITO/SnO₂/KCl/Cs_0.05 (MA_0.17FA_0.83)_0.95Pb(I_0.83Br_0.17)₃/spiro/Au) was prepared using a low temperature (no higher than 100 °C) solution process, and the device with the highest efficiency of 16.16% was obtained by adjusting the concentration of the KCl modified layer. Meanwhile, the efficiency of the large area (1 cm²) flexible solar cell was higher than 13%. At the same time, the passivation of the KCl interface modification layer inhibits the formation of the defect states, which reduced the surface recombination of the perovskite and improved the carrier transport performance, and the hysteresis effect of the device was also reduced accordingly.

Key words: Flexible solar cells, Perovskite, KCl, NaCl, Interfacial modification

Xiaofang Ye, Hongkun Cai, Jian Su, Jingtao Yang, Jian Ni, Juan Li, Jianjun Zhang. Preparation of hysteresis-free flexible perovskite solar cells via interfacial modification[J]. J. Mater. Sci. Technol., 2021, 61: 213-220.

Figures/Tables 15

Fig. 1. Schematic diagram of the device structure.

Fig. 2. Schematic illustration of one-step spin-coating of perovskite ?lms.

Fig. 3. (a) Optical image of KCl solution directly dropped onto SnO2 film. Water contact angles of SnO2 films without (b) and with (c) ultraviolet ozone treatment.

Fig. 4. (a) XRD pattens of perovskite films modified with different concentrations of KCl (0 mg/mL, 1 mg/mL, 2 mg/mL, 5 mg/mL and 10 mg/mL). (b) Dependence of X-ray diffraction (XRD) peak intensity ratio of PbI2 and (110) peaks on various content of KCl modification layers.

Fig. 5. SEM images of perovskite films modified with KCl solution: (a) 0 mg/mL, (b) 1 mg/mL, (c) 2 mg/ mL, (d) 5 mg/mL and (e) 10 mg/mL.

Fig. 6. (a) Light absorption curves depending on wavelength of perovskite films with different KCl modifications. (b) UV-vis absorption spectra (left Y-axis) and PL spectra (right Y-axis) of perovskite thin films obtained after modified with various concentrations of KCl. (c) Time resolution photoluminescence (TRPL) analysis of perovskite films.

Table 1 TRPL parameters fitted by a bi-exponential decay functiona.

Samples	τ₁ (ns)	A₁	τ₂ (ns)	A₂	τ_ave (ns)^b
ITO/PVK	0.3322	16069.028	140.2	134.108	109.271
ITO/ SnO₂/PVK	0.3312	11181.638	203.3	144.385	180.561
ITO/SnO₂/KCl (1 mg/mL)/PVK	0.3313	16961.697	243.1	155.816	211.737
ITO/SnO₂/KCl (2 mg/mL)/PVK	0.2818	25802.807	332.0	89.209	266.614
ITO/SnO₂/KCl (5 mg/mL)/PVK	0.3215	19313.563	288.8	129.569	240.097

Fig. 7. (a) J-V curves, (b) normalized steady-state photocurrent density and (c) steady-state output efficient of the best devices with various amounts of the interfacial KCl layer measured at a maximum power point.

Table 2 Steady-state power output and PCEs of the corresponding devices.

KCl (mg/mL)	Steady-state power output (%)	PCE (%)
0	13.02	13.40
1	14.28	14.95
2	16.77	16.16
5	14.96	15.07

Fig. 8. Electrochemical impedance spectra (EIS) for the perovskite solar cells with different concentrations of KCl (0 mg/mL, 1 mg/mL, 2 mg/mL and 5 mg/mL). The equivalent circuit of this study is presented in the inset.

Table 3 Parameter values of the equivalent circuit.

KCl (mg/mL)	R_s (Ω)	R_ct (Ω)	C_ct (F)
0	16.48	71.75	1.79 × 10^-8
1	15.42	54.4	1.94 × 10^-8
2	15.19	49.38	2.67 × 10^-8
5	15.24	52.85	1.36 × 10^-8

Fig. 9. (a) Light absorption curves of ITO/SnO2 and ITO/SnO2/KCl films. (b) UPS spectra of ITO/SnO2 and ITO/SnO2/KCl (2 mg/mL). (c) Energy-level diagrams of the various films resulting from the UPS studies. The Fermi level (Ef) values of each film are aligned due to the thermodynamic equilibrium that arises when they are joined together.

Fig. 10. J-V curves of perovskite solar cells modified with (a) KCl and (b) NaCl solution measured at reverse and forward scans at a normal rate.

Fig. 11. Dependence of hysteresis effect index on different interface modification materials between SnO2 and perovskite.

Fig. 12. (a) Statistical photovoltaic parameters of Voc, Jsc, FF and PCE, (b) histograms of PCE distribution statistics for the flexible large-area (1 cm2) perovskite solar cells with different KCl modifications. The data for each condition were calculated based on 30 separate cells.

References 33

[1]	A. Kojima, K. Teshima, Y. Shirai, T. Miyasaka, J. Am. Chem. Soc. 131 (2009) 6050. URL PMID
[2]	Best Research-Cell Efficiencies, NREL, 2020 https://www.nrel.gov/pv/assets/pdfs/best-research-cell-efficiencies.20200406.pdf.
[3]	C. Wang, L. Guan, D. Zhao, Y. Yu, C.R. Grice, Z. Song, R.A. Awni, J. Chen, J. Wang, X. Zhao, Y. Yan, ACS Energy Lett. 2 (2017) 2118-2124.
[4]	D. Yang, R.X. Yang, S. Priya, S.Z. Liu, Angew. Chem. Int. Ed. 58 (2019) 4466-4483.
[5]	M.H. Kumar, N. Yantara, S. Dharani, M. Graetzel, S. Mhaisalkar, P.P. Boix, N. Mathews, Chem. Commun. 49 (2013) 11089-11091.
[6]	J. Feng, X. Zhu, Z. Yang, X. Zhang, J. Niu, Z. Wang, S. Zuo, S. Priya, S. Liu, D. Yang, Adv. Mater. 30 (2018), 1801418.
[7]	B. Ding, S.Y. Huang, Q.Q. Chu, Y. Li, C.X. Li, C.J. Li, G.J. Yang, J. Mater. Chem. A 6 (2018) 10233-10242.
[8]	C. Liu, L. Zhang, X. Zhou, J. Gao, W. Chen, X. Wang, B. Xu, Adv. Funct. Mater. 29 (2019), 1807604.
[9]	J. Su, H. Cai, X. Ye, X. Zhou, J. Yang, D. Wang, J. Ni, J. Li, J. Zhang, ACS Appl. Mater. Interfaces 11 (2019) 10689-10696. URL PMID
[10]	J.H. Heo, H.J. Han, D. Kim, T.K. Ahn, S.H. Im, Energy Environ. Sci. 8 (2015) 1602-1608.
[11]	D. Yang, R. Yang, K. Wang, C. Wu, X. Zhu, J. Feng, X. Ren, G. Fang, S. Priya, S. Liu, Nat. Commun. 9 (2018) 3239. DOI URL PMID
[12]	P. Liu, W. Wang, S. Liu, H. Yang, Z. Shao, Adv. Energy Mater. 9 (2019) 1803017. DOI URL
[13]	J.W. Lee, S.G. Kim, S.H. Bae, D.K. Lee, O. Lin, Y. Yang, N.G. Park, Nano Lett. 17 (2017) 4270-4276. URL PMID
[14]	H. Wang, A. Guerrero, A. Bou, A.M. Al-Mayouf, J. Bisquert, 12 (2019) 2054-2079.
[15]	T. Bu, X. Liu, Y. Zhou, J. Yi, X. Huang, L. Luo, J. Xiao, Z. Ku, Y. Peng, F. Huang, Y.-B. Cheng, J. Zhong, Energy Environ. Sci. 10 (2017) 2509-2515. DOI URL
[16]	X. Liu, Y. Zhang, L. Shi, Z. Liu, J. Huang, J.S. Yun, Y. Zeng, A. Pu, K. Sun, Z. Hameiri, J.A. Stride, J. Seidel, M.A. Green, X. Hao, Adv. Energy Mater. 8 (2018), 1800138. DOI URL
[17]	Z. Li, F. Wang, C. Liu, F. Gao, L. Shen, W. Guo, J. Mater. Chem. A 7 (2019) 22359-22365. DOI URL
[18]	N. Zhu, X. Qi, Y. Zhang, G. Liu, C. Wu, D. Wang, X. Guo, W. Luo, X. Li, H. Hu, Z. Chen, L. Xiao, B. Qu, ACS Appl. Energy Mater. 2 (2019) 3676-3682. DOI URL
[19]	P. Zhu, S. Gu, X. Luo, Y. Gao, S. Li, J. Zhu, H. Tan, Adv. Energy Mater. 10 (2020), 1903083. DOI URL
[20]	N. Li, S. Tao, Y. Chen, X. Niu, C.K. Onwudinanti, C. Hu, Z. Qiu, Z. Xu, G. Zheng, L. Wang, Y. Zhang, L. Li, H. Liu, Y. Lun, J. Hong, X. Wang, Y. Liu, H. Xie, Y. Gao, Y. Bai, S. Yang, G. Brocks, Q. Chen, H. Zhou, Nat. Energy 4 (2019) 408-415. DOI URL
[21]	P. Zhao, W. Yin, M. Kim, M. Han, Y.J. Song, T.K. Ahn, H.S. Jung, J. Mater. Chem. A 5 (2017) 7905-7911. DOI URL
[22]	J. Chang, Z. Lin, H. Zhu, F.H. Isikgor, Q.H. Xu, C. Zhang, Y. Hao, J. Ouyang, J. Mater. Chem. A 4 (2016) 16546-16552. DOI URL
[23]	F. Zheng, W. Chen, T. Bu, K.P. Ghiggino, F. Huang, Y. Cheng, P. Tapping, T.W. Kee, B. Jia, X. Wen, Adv. Energy Mater. 9 (2019), 1901016. DOI URL
[24]	H. Tan, A. Jain, O. Voznyy, X. Lan, F.P.G. de Arquer, J.Z. Fan, R. Quintero-Bermudez, M. Yuan, B. Zhang, Y. Zhao, F. Fan, P. Li, L.N. Quan, Y. Zhao, Z.H. Lu, Z. Yang, S. Hoogland, E.H. Sargent, Science 355 (2017) 722-726. DOI URL PMID
[25]	J. Khan, X. Yang, K. Qiao, H. Deng, J. Zhang, Z. Liu, W. Ahmad, J. Zhang, D. Li, H. Liu, H. Song, C. Cheng, J. Tang, J. Mater. Chem. A 5 (2017) 17240-17247. DOI URL
[26]	M. Saliba, T. Matsui, J.Y. Seo, K. Domanski, J.P. Correa-Baena, M.K. Nazeeruddin, S.M. Zakeeruddin, W. Tress, A. Abate, A. Hagfeldt, M. Gratzel, Energy Environ. Sci. 9 (2016) 1989-1997. DOI URL PMID
[27]	K.M. Boopathi, R. Mohan, T.Y. Huang, W. Budiawan, M.Y. Lin, C.H. Lee, K.C. Ho, C.W. Chu, J. Mater. Chem. A 4 (2016) 1591-1597. DOI URL
[28]	Q. Chen, H. Zhou, T.B. Song, S. Luo, Z. Hong, H.S. Duan, L. Dou, Y. Liu, Y. Yang, Nano Lett. 14 (2014) 4158-4163. DOI URL PMID
[29]	C. Wang, C. Xiao, Y. Yu, D. Zhao, R.A. Awni, C.R. Grice, K. Ghimire, I. Constantinou, W. Liao, A.J. Cimaroli, P. Liu, J. Chen, N.J. Podraza, C.S. Jiang, M.M. Al-Jassim, X. Zhao, Y. Yan, Adv. Energy Mater. 7 (2017), 1700414. DOI URL
[30]	C. Bi, X. Zheng, B. Chen, H. Wei, J. Huang, ACS Energy Lett. 2 (2017) 1400-1406. DOI URL
[31]	D. Wang, C. Wu, W. Luo, X. Guo, B. Qu, L. Xiao, Z. Chen, ACS Appl. Energy Mater. 1 (2018) 2215-2221. DOI URL
[32]	D.Y. Son, S.G. Kim, J.Y. Seo, S.H. Lee, H. Shin, D. Lee, N.G. Park, J. Am. Chem. Soc. 140 (2018) 1358-1364. URL PMID
[33]	Z. Tang, S. Uchida, T. Bessho, T. Kinoshita, H. Wang, F. Awai, R. Jono, M.M. Maitani, J. Nakazaki, T. Kubo, H. Segawa, Nano Energy 45 (2018) 184-192. DOI URL