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http://dx.doi.org/10.4191/kcers.2018.55.4.09

Recent Progress in Flexible Perovskite Solar Cell Development  

Ren, Xiaodong (School of Advanced Materials Science & Engineering, Sungkyunkwan University)
Jung, Hyun Suk (School of Advanced Materials Science & Engineering, Sungkyunkwan University)
Publication Information
Journal of the Korean Ceramic Society / v.55, no.4, 2018 , pp. 325-336 More about this Journal
Abstract
Perovskite solar cells (PSCs) are a new class of photovoltaic devices, which have attracted significant attention due to their remarkable optoelectrical properties, including high absorption coefficients, high carrier mobilities, long carrier diffusion lengths, tunable bandgaps, low cost, and facile fabrication. PSCs have reached efficiencies of 22.70% and 18.36% on rigid fluorine-doped tin oxide and poly(ethylene terephthalate) substrates, respectively; these are comparable to those of single-crystal silicon and copper-indium-gallium-selenium solar cells. Over the past eight years, the photo conversion efficiency of PSCs has been significantly improved by device-architecture adjustments, and absorber and electron/hole transport layer optimization. Each layer is important for the performance of PSCs; hence, we discuss achievements in flexible perovskite solar cells (FPSCs), covering electron/hole-transport materials, electrode materials. We give a comprehensive overview of FPSCs and put forward suggestions for their further development.
Keywords
Perovskite solar cells; Flexibility; Metal oxide;
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1 Z. Zhu, Y. Bai, X. Liu, C. C. Chueh, S. Yang, and A. K. Jen, "Enhanced Efficiency and Stability of Inverted Perovskite Solar Cells Using Highly Crystalline $SnO_2$ Nanocrystals as the Robust Electron-Transporting Layer," Adv. Mater., 28 [30] 6478-84 (2016).   DOI
2 H. C. Weerasinghe, P. M. Sirimanne, G. V. Franks, G. P. Simon, and Y. B. Cheng, "Low Temperature Chemically Sintered Nano-Crystalline $TiO_2$ Electrodes for Flexible Dye-Sensitized Solar Cells," J. Photochem. Photobiol., A, 213 [1] 30-6 (2010).   DOI
3 F. Di Giacomo, V. Zardetto, A. D'Epifanio, S. Pescetelli, F. Matteocci, S. Razza, A. Di Carlo, S. Licoccia, W. M. M. Kessels, M. Creatore, and T. M. Brown, "Flexible Perovskite Photovoltaic Modules and Solar Cells Based on Atomic Layer Deposited Compact Layers and UV-Irradiated $TiO_2$ Scaffolds on Plastic Substrates," Adv. Energy Mater., 5 [8] 1401808 (2015).   DOI
4 P. Docampo, J. M. Ball, M. Darwich, G. E. Eperon, and H. J. Snaith, "Efficient Organometal Trihalide Perovskite Planar-Heterojunction Solar Cells on Flexible Polymer Substrates," Nat. Commun., 4 2761 (2013).   DOI
5 K. G. Lim, H. B. Kim, J. Jeong, H. Kim, J. Y. Kim, and T. W. Lee, "Boosting the Power Conversion Efficiency of Perovskite Solar Cells Using Self-Organized Polymeric Hole Extraction Layers with High Work Function," Adv. Mater., 26 [37] 6461-66 (2014).   DOI
6 C. Roldan-Carmona, O. Malinkiewicz, A. Soriano, G. Minguez Espallargas, A. Garcia, P. Reinecke, T. Kroyer, M. I. Dar, M. K. Nazeeruddin, and H. J. Bolink, "Flexible High Efficiency Perovskite Solar Cells," Energy Environ. Sci., 7 [3] 994-97 (2014).   DOI
7 K. Poorkazem, D. Liu, and T. L. Kelly, "Fatigue Resistance of a Flexible, Efficient, and Metal Oxide-Free Perovskite Solar Cell," J. Mater. Chem. A, 3 [17] 9241-48 (2015).   DOI
8 S. I. Na, S. S. Kim, J. Jo, and D. Y. Kim, "Efficient and Flexible ITO-Free Organic Solar Cells Using Highly Conductive Polymer Anodes," Adv. Mater., 20 [21] 4061-67 (2008).   DOI
9 B. J. Kim, D. H. Kim, Y.-Y. Lee, H.-W. Shin, G. S. Han, J. S. Hong, K. Mahmood, T. K. Ahn, Y.-C. Joo, K. S. Hong, N.-G. Park, S. Lee, and H. S. Jung, "Highly Efficient and Bending Durable Perovskite Solar Cells: Toward a Wearable Power Source," Energy Environ. Sci., 8 [3] 916-21 (2015).   DOI
10 C. Lungenschmied, G. Dennler, H. Neugebauer, S. N. Sariciftci, M. Glatthaar, T. Meyer, and A. Meyer, "Flexible, Long-Lived, Large-Area, Organic Solar Cells," Sol. Energy Mater. Sol. Cells, 91 [5] 379-84 (2007).   DOI
11 B. Susrutha, L. Giribabu, and S. P. Singh, "Recent Advances in Flexible Perovskite Solar Cells," Chem. Commun., 51 [79] 14696-707 (2015).   DOI
12 M. Liu, M. B. Johnston, and H. J. Snaith, "Efficient Planar Heterojunction Perovskite Solar Cells by Vapour Deposition," Nature, 501 [7467] 395-98 (2013).   DOI
13 J. H. Im, C. R. Lee, J. W. Lee, S. W. Park, and N. G. Park, "6.5% Efficient Perovskite Quantum-Dot-Sensitized Solar Cell," Nanoscale, 3 [10] 4088-93 (2011).   DOI
14 H. S. Kim, C. R. Lee, J. H. Im, K. B. Lee, T. Moehl, A. Marchioro, S. J. Moon, R. Humphry-Baker, J. H. Yum, J. E. Moser, M. Gratzel, and N. G. Park, "Lead Iodide Perovskite Sensitized All-Solid-State Submicron Thin Film Mesoscopic Solar Cell with Efficiency Exceeding 9%," Sci. Rep., 2 591 (2012).   DOI
15 M. M. Lee, J. Teuscher, T. Miyasaka, T. N. Murakami, and H. J. Snaith, "Efficient Hybrid Solar Cells Based on Meso-Superstructured Organometal Halide Perovskites," Science, 338 [6107] 643-47 (2012).   DOI
16 L. Grinis, S. Kotlyar, S. Ruhle, J. Grinblat, and A. Zaban, "Conformal Nano-Sized Inorganic Coatings on Mesoporous $TiO_2$ Films for Low-Temperature Dye-Sensitized Solar Cell Fabrication," Adv. Func. Mater., 20 [2] 282-88 (2010).   DOI
17 N. J. Jeon, J. H. Noh, Y. C. Kim, W. S. Yang, S. Ryu, and S. I. Seok, "Solvent Engineering for High-Performance Inorganic-Organic Hybrid Perovskite Solar Cells," Nat. Mater., 13 [9] 897-903 (2014).   DOI
18 H. C. Weerasinghe, F. Huang, and Y.-B. Cheng, "Fabrication of Flexible Dye Sensitized Solar Cells on Plastic Substrates," Nano Energy, 2 [2] 174-89 (2013).   DOI
19 D. Yang, R. X. Yang, J. Zhang, Z. Yang, S. Z. Liu, and C. Li, "High Efficiency Flexible Perovskite Solar Cells using Superior Low Temperature $TiO_2$," Energy Environ. Sci., 8 [11] 3208-14 (2015).   DOI
20 S. S. Mali, C. K. Hong, A. I. Inamdar, H. Im, and S. E. Shim, "Efficient Planar n-i-p Type Heterojunction Flexible Perovskite Solar Cells with Sputtered $TiO_2$ Electron Transporting Layers," Nanoscale, 9 [9] 3095-104 (2017).   DOI
21 F. D. Giacomo, V. Zardetto, A. D'Epifanio, S. Pescetelli, F. Matteocci, S. Razza, A. D. Carlo, S. Licoccia, W. M. M. Kessels, M. Creatore, and T. M. Brown, "Flexible Perovskite Photovoltaic Modules and Solar Cells Based on Atomic Layer Deposited Compact Layers and UV-Irradiated $TiO_2$ Scaffolds on Plastic Substrates," Adv. Energy Mater., 5 [8] 1401808 (2015).   DOI
22 M. H. Kumar, N. Yantara, S. Dharani, M. Graetzel, S. Mhaisalkar, P. P. Boix, and N. Mathews, "Flexible, Low-Temperature, Solution Processed ZnO-Based Perovskite Solid State Solar Cells," Chem. Commun., 49 [94] 11089-91 (2013).   DOI
23 J. H. Heo, M. H. Lee, H. J. Han, B. R. Patil, J. S. Yu, and S. H. Im, "Highly Efficient Low Temperature Solution Processable Planar Type $CH_3NH_3PbI_3$ Perovskite Flexible Solar Cells," J.Mater. Chem. A, 4 [5] 1572-78 (2016).   DOI
24 A. Chirila, S. Buecheler, F. Pianezzi, P. Bloesch, C. Gretener, A. R. Uhl, C. Fella, L. Kranz, J. Perrenoud, S. Seyrling, R. Verma, S. Nishiwaki, Y. E. Romanyuk, G. Bilger, and A. N. Tiwari, "Highly Efficient $Cu(In,Ga)Se_2$ Solar Cells Grown on Flexible Polymer Films," Nat. Mater., 10 [11] 857-61 (2011).   DOI
25 A. Banerjee, T. Su, D. Beglau, G. Pietka, F. S. Liu, S. Almutawalli, J. Yang, and S. Guha, "High-Efficiency, Multijunction nc-Si:H-Based Solar Cells at High Deposition Rate," IEEE J. Photovoltaics, 2 [2] 9-103 (2012).
26 A. Banerjee, F. S. Liu, D. B., T. Su, G. Pietka, J. Yang, and S. Guha, "12.0% Efficiency on Large-Area, Encapsulated, Multijunction nc-Si:H-Based Solar Cells," IEEE J. Photovoltaics, 2 104-8 (2012).   DOI
27 X. Ren, W. Zi, Q. Ma, F. Xiao, F. Gao, S. Hu, Y. Zhou, and S. Liu, "Topology and Texture Controlled ZnO Thin Film Electrodeposition for Superior Solar Cell Efficiency," Sol. Energy Mater. Sol. Cells, 134 54-9 (2015).   DOI
28 W. Zi, X. Ren, F. Xiao, H. Wang, F. Gao, and S. Liu, "Ag Nanoparticle Enhanced Light Trapping in Hydrogenated Amorphous Silicon Germanium Solar Cells on Flexible Stainless Steel Substrate," Sol. Energy Mater. Sol. Cells, 144 63-7 (2016).   DOI
29 S. Ishizuka, A. Yamada, K. Matsubara, P. Fons, K. Sakurai, and S. Niki, "Development of High-Efficiency Flexible $Cu(In,Ga)Se_2$ Solar Cells: A Study of Alkali Doping Effects on CIS, CIGS, and CGS Using Alkali-Silicate Glass Thin Layers," Curr. Appl. Phys., 10 [2] S154-56 (2010).   DOI
30 A. Romeo, G. Khrypunov, F. Kurdesau, M. Arnold, D. L. Batzner, H. Zogg, and A. N. Tiwari, "High-Efficiency Flexible CdTe Solar Cells on Polymer Substrates," Sol. Energy Mater. Sol. Cells, 90 [18] 3407-15 (2006).   DOI
31 M. Lee, Y. Jo, D. S. Kim, and Y. Jun, "Flexible Organo-Metal Halide Perovskite Solar Cells on a Ti Metal Substrate," J. Mater. Chem. A, 3 [8] 4129-33 (2015).   DOI
32 P. Docampo, J. M. Ball, M. Darwich, G. E. Eperon, and H. J. Snaith, "Efficient Organometal Trihalide Perovskite Planar-Heterojunction Solar Cells on Flexible Polymer Substrates," Nat. Commun., 4 2761 (2013).   DOI
33 J. Yoon, H. Sung, G. Lee, W. Cho, N. Ahn, H. S. Jung, and M. Choi, "Superflexible, High-Efficiency Perovskite Solar Cells Utilizing Graphene Electrodes: Towards Future Foldable Power Sources," Energy Environ. Sci., 10 [1] 337-45 (2017).   DOI
34 Y. Li, L. Meng, Y. M. Yang, G. Xu, Z. Hong, Q. Chen, J. You, G. Li, Y. Yang, and Y. Li, "High-Efficiency Robust Perovskite Solar Cells on Ultrathin Flexible Substrates," Nat. Commun., 7 10214 (2016).   DOI
35 C. Roldan-Carmona, O. Malinkiewicz, A. Soriano, G. Minguez Espallargas, A. Garcia, P. Reinecke, T. Kroyer, M. I. Dar, M. K. Nazeeruddin, and H. J. Bolink, "Flexible High Efficiency Perovskite Solar Cells," Energy Environ. Sci., 7 [3] 994 (2014).   DOI
36 Q. Wei, Z. Yang, D. Yang, W. Zi, X. Ren, Y. Liu, X. Liu, J. Feng, and S. Liu, "The Effect of Transparent Conductive Oxide on The Performance $CH_3NH_3PbI_3$ Perovskite Solar Cell without Electron/Hole Selective Layers," Sol. Energy, 135 654-61 (2016).   DOI
37 J. Troughton, D. Bryant, K. Wojciechowski, M. J. Carnie, H. Snaith, D. A. Worsley, and T. M. Watson, "Highly Efficient, Flexible, Indium-Free Perovskite Solar Cells Employing Metallic Substrates," J. Mater. Chem. A, 3 [17] 9141-45 (2015).   DOI
38 H. Lu, J. Sun, H. Zhang, S. Lu, and W. C. Choy, "Room-Temperature Solution-Processed and Metal Oxide-Free Nano-Composite for the Flexible Transparent Bottom Electrode of Perovskite Solar Cells," Nanoscale, 8 [11] 5946-53 (2016).   DOI
39 J. You, Z. Hong, Y. Yang, Q. Chen, M. Cai, T.-B. Song, C.-C. Chen, S. Lu, Y. Liu, H. Zhou, and Y. Yang, "Low-Temperature Solution-Processed Perovskite Solar Cells with High Efficiency and Flexibility," ACS Nano, 8 [2] 1674-80 (2014).   DOI
40 K. Wang, Y. Shi, Q. Dong, Y. Li, S. Wang, X. Yu, M. Wu, and T. Ma, "Low-Temperature and Solution-Processed Amorphous $WO_X$ as Electron-Selective Layer for Perovskite Solar Cells," J. Phys. Chem. Lett., 6 [5] 755-59 (2015).   DOI
41 C. Wang, D. Zhao, C. R. Grice, W. Liao, Y. Yu, A. Cimaroli, N. Shrestha, P. J. Roland, J. Chen, Z. Yu, P. Liu, N. Cheng, R. J. Ellingson, X. Zhao, and Y. Yan, "Low-Temperature Plasma-Enhanced Atomic Layer Deposition of Tin Oxide Electron Selective Layers for Highly Efficient Planar Perovskite Solar Cells," J.Mater. Chem. A, 4 [31] 12080-87 (2016).   DOI
42 M. Kaltenbrunner, M. S. White, E. D. Glowacki, T. Sekitani, T. Someya, N. S. Sariciftci, and S. Bauer, "Ultrathin and lightweight Organic Solar Cells with High Flexibility," Nat. Commun., 3 770 (2012).   DOI
43 T.-Y. Chen, Y.-J. Huang, C.-T. Li, C.-W. Kung, R. Vittal, and K.-C. Ho, "Metal-Organic Framework/Sulfonated Polythiophene on Carbon Cloth as a Flexible Counter Electrode for Dye-Sensitized Solar Cells," Nano Energy, 32 19-27 (2017).   DOI
44 Z. Xu, T. Li, Q. Liu, F. Zhang, X. Hong, S. Xie, C. Lin, X. Liu, and W. Guo, "Controllable and Large-Scale Fabrication of Rectangular CuS Network Films for Indium Tin Oxide and Pt-Free Flexible Dye-Sensitized Solar Cells," Sol. Energy Mater. Sol. Cells, 179 297-304 (2018).   DOI
45 J. S. Feng, Z. Yang, D. Yang, X. D. Ren, X. J. Zhu, Z. W. Jin, W. Zi, Q. B. Wei, and S. Z. Liu, "E-Beam Evaporated $Nb_2O_5$ as an Effective Electron Transport Layer for Large Flexible Perovskite Solar Cells," Nano Energy, 36 1-8 (2017).   DOI
46 W. Chen, Y. Z. Wu, Y. F. Yue, J. Liu, W. J. Zhang, X. D. Yang, H. Chen, E. B. Bi, I. Ashraful, M. Gratzel, and L. Y. Han, "Efficient and Stable Large-Area Perovskite Solar Cells with Inorganic Charge Extraction Layers," Science, 350 [6263] 944-48 (2015).   DOI
47 L. Kranz, C. Gretener, J. Perrenoud, R. Schmitt, F. Pianezzi, F. La Mattina, P. Blosch, E. Cheah, A. Chirila, C. M. Fella, H. Hagendorfer, T. Jager, S. Nishiwaki, A. R. Uhl, S. Buecheler, and A. N. Tiwari, "Doping of Polycrystalline CdTe for High-Efficiency Solar Cells on Flexible Metal Foil," Nat. Commun., 4 2306 (2013).   DOI
48 W. S. Yang, B.-W. Park, E. H. Jung, N. J. Jeon, Y. C. Kim, D. U. Lee, S. S. Shin, J. Seo, E. K. Kim, J. H. Noh, and S. I. Seok, "Iodide Management in Formamidinium-Lead-Halide-Based Perovskite Layers for Efficient Solar Cells," Science, 356 1376-79 (2017).   DOI
49 N. Arora, M. I. Dar, A. Hinderhofer, N. Pellet, F. Schreiber, S. M. Zakeeruddin, and M. Gratzel, "Perovskite Solar Cells with CuSCN Hole Extraction Layers Yield Stabilized Efficiencies Greater than 20%," Science, 358 [6364] 768-71 (2017).
50 D. Yang, R. Yang, X. Ren, X. Zhu, Z. Yang, C. Li, and S. F. Liu, "Hysteresis-Suppressed High-Efficiency Flexible Perovskite Solar Cells Using Solid-State Ionic-Liquids for Effective Electron Transport," Adv. Mater., 28 [26] 5206-13 (2016).   DOI
51 P. W. Liang, C. Y. Liao, C. C. Chueh, F. Zuo, S. T. Williams, X. K. Xin, J. J. Lin, and A. K. Y. Jen, "Additive Enhanced Crystallization of Solution-Processed Perovskite for Highly Efficient Planar-Heterojunction Solar Cells," Adv. Mater., 26 [22] 3748-54 (2014).   DOI
52 H. P. Zhou, Q. Chen, G. Li, S. Luo, T. B. Song, H. S. Duan, Z. R. Hong, J. B. You, Y. S. Liu, and Y. Yang, "Interface Engineering of Highly Efficient Perovskite Solar Cells," Science, 345 [6196] 542-46 (2014).   DOI
53 T. Liu, D. Kim, H. Han, A. R. Yusoff, and J. Jang, "Fine-Tuning Optical and Electronic Properties of Graphene Oxide for Highly Efficient Perovskite Solar Cells," Nanoscale, 7 [24] 10708-18 (2015).   DOI
54 D. G. Lee, D. Lee, J. S. Yoo, S. Lee, and H. S. Jung, "Effective Passivation of Ag Nanowire-Based Flexible Transparent Conducting Electrode by $TiO_2$ Nanoshell," Nano Convergence, 3 [1] 20 (2016).   DOI
55 I. Jeon, J. Yoon, N. Ahn, M. Atwa, C. Delacou, A. Anisimov, E. I. Kauppinen, M. Choi, S. Maruyama, and Y. Matsuo, "Carbon Nanotubes versus Graphene as Flexible Transparent Electrodes in Inverted Perovskite Solar Cells," J. Phys. Chem. Lett., 8 [21] 5395-401 (2017).   DOI
56 Q. Luo, H. Ma, F. Hao, Q. Hou, J. Ren, L. Wu, Z. Yao, Y. Zhou, N. Wang, K. Jiang, H. Lin, and Z. Guo, "Carbon Nanotube Based Inverted Flexible Perovskite Solar Cells with All-Inorganic Charge Contacts," Adv. Func. Mater., 27 [42] 1703068 (2017).   DOI
57 M. Kaltenbrunner, G. Adam, E. D. Glowacki, M. Drack, R. Schwodiauer, L. Leonat, D. H. Apaydin, H. Groiss, M. C. Scharber, M. S. White, N. S. Sariciftci, and S. Bauer, "Flexible High Power-Per-Weight Perovskite Solar Cells with Chromium Oxide-Metal Contacts for Improved Stability in Air," Nat. Mater., 14 [10] 1032-39 (2015).   DOI
58 H. Zhang, J. Cheng, F. Lin, H. He, J. Mao, K. S. Wong, A. K. Jen, and W. C. Choy, "Pinhole-Free and Surface-Nanostructured NiO Film by Room-Temperature Solution Process for High-Performance Flexible Perovskite Solar Cells with Good Stability and Reproducibility," ACS Nano, 10 [1] 1503-11 (2015).   DOI
59 J. S. Kang, J.-Y. Kim, J. Yoon, J. Kim, J. Yang, D. Y. Chung, M.-C. Kim, H. Jeong, Y. J. Son, B. G. Kim, J. Jeong, T. Hyeon, M. Choi, M. J. Ko, and Y.-E. Sung, "Room-Temperature Vapor Deposition of Cobalt Nitride Nanofilms for Mesoscopic and Perovskite Solar Cells," Adv. Sci., 8 [13] 1703114 (2018).
60 P.-L. Qin, Q. He, C. Chen, X.-L. Zheng, G. Yang, H. Tao, L.-B. Xiong, L. Xiong, G. Li, and G.-J. Fang, "High-Performance Rigid and Flexible Perovskite Solar Cells with Low-Temperature Solution-Processable Binary Metal Oxide Hole-Transporting Materials," Sol. RRL, 1 [8] 1700058 (2017).   DOI
61 B. Abdollahi Nejand, P. Nazari, S. Gharibzadeh, V. Ahmadi, and A. Moshaii, "All-Inorganic Large-Area Low-Cost and Durable Flexible Perovskite Solar Cells Using Copper Foil as a Substrate," Chem. Commun., 53 [4] 747-50 (2017).   DOI
62 J. W. Jo, M.-S. Seo, M. Park, J.-Y. Kim, J. S. Park, I. K. Han, H. Ahn, J. W. Jung, B.-H. Sohn, M. J. Ko, and H. J. Son, "Improving Performance and Stability of Flexible Planar-Heterojunction Perovskite Solar Cells Using Polymeric Hole-Transport Material," Adv. Funct. Mater., 26 [25] 4464-71 (2016).   DOI
63 J. Han, S. Yuan, L. Liu, X. Qiu, H. Gong, X. Yang, C. Li, Y. Hao, and B. Cao, "Fully Indium-Free Flexible Ag Nanowires/ZnO:F Composite Transparent Conductive Electrodes with High Haze," J. Mater. Chem. A, 3 [10] 5375-84 (2015).   DOI
64 Z. Gu, L. Zuo, T. T. Larsen-Olsen, T. Ye, G. Wu, F. C. Krebs, and H. Chen, "Interfacial Engineering of Self-Assembled Monolayer Modified Semi-Roll-to-Roll Planar Heterojunction Perovskite Solar Cells on Flexible Substrates," J. Mater. Chem. A, 3 [48] 24254-60 (2015).   DOI
65 L. Wang, W. F. Fu, Z. W. Gu, C. C. Fan, X. Yang, H. Y. Li, and H. Z. Chen, "Low Temperature Solution Processed Planar Heterojunction Perovskite Solar Cells with a Cdse Nanocrystal as an Electron Transport/Extraction Layer," J.Mater. Chem. C, 2 [43] 9087-90 (2014).   DOI
66 M. Xiao, F. Huang, W. Huang, Y. Dkhissi, Y. Zhu, J. Etheridge, A. Gray-Weale, U. Bach, Y. B. Cheng, and L. Spiccia, "A Fast Deposition-Crystallization Procedure for Highly Efficient Lead Iodide Perovskite Thin-Film Solar Cells," Angew. Chem., Int. Ed. Engl., 53 [37] 9898-903 (2014).   DOI
67 J. X. Song, E. Q. Zheng, J. Bian, X. F. Wang, W. J. Tian, Y. Sanehira, and T. Miyasaka, "Low-Temperature $SnO_2$-Based Electron Selective Contact for Efficient and Stable Perovskite Solar Cells," J. Mater. Chem. A, 3 [20] 10837-44 (2015).   DOI
68 W. Y. Nie, H. H. Tsai, R. Asadpour, J. C. Blancon, A. J. Neukirch, G. Gupta, J. J. Crochet, M. Chhowalla, S. Tretiak, M. A. Alam, H. L. Wang, and A. D. Mohite, "High-Efficiency Solution-Processed Perovskite Solar Cells with Millimeter-Scale Grains," Science, 347 [6221] 522-25 (2015).   DOI
69 X. Li, D. Bi, C. Yi, J. D. Decoppet, J. Luo, S. M. Zakeeruddin, A. Hagfeldt, and M. Gratzel, "A Vacuum Flash-Assisted Solution Process for High-Efficiency Large-Area Perovskite Solar Cells," Science, 353 [6294] 58-62 (2016).   DOI
70 D. Y. Liu and T. L. Kelly, "Perovskite Solar Cells with A Planar Heterojunction Structure Prepared Using Room-Temperature Solution Processing Techniques," Nat. Photonics, 8 [2] 133-38 (2014).   DOI
71 N. R. E. Laboratory, Best Research-Cell Efficiencies, http://www.nrel.gov/ncpv/images/efficiency_chart.jpg. Accessed on 09/04/2018.
72 A. Kogo, M. Ikegami, and T. Miyasaka, "A $SnO_x$-Brookite $TiO_2$ Bilayer Electron Collector for Hysteresis-Less High Efficiency Plastic Perovskite Solar Cells Fabricated at Low Process Temperature," Chem. Commun., 52 [52] 8119-22 (2016).   DOI
73 S. S. Shin, W. S. Yang, J. H. Noh, J. H. Suk, N. J. Jeon, J. H. Park, J. S. Kim, W. M. Seong, and S. I. Seok, "High-Performance Flexible Perovskite Solar Cells Exploiting $Zn_2SnO_4$ Prepared in Solution Below 100 Degrees C," Nat. Commun., 6 7410 (2015).   DOI
74 C. Wang, L. Guan, D. Zhao, Y. Yu, C. R. Grice, Z. Song, R. A. Awni, J. Chen, J. Wang, X. Zhao, and Y. Yan, "Water Vapor Treatment of Low-Temperature Deposited $SnO_2$ Electron Selective Layers for Efficient Flexible Perovskite Solar Cells," ACS Energy Lett., 2 [9] 2118-24 (2017).   DOI
75 A. Kojima, K. Teshima, Y. Shirai, and T. Miyasaka, "Organometal Halide Perovskites as Visible-Light Sensitizers for Photovoltaic Cells," J. Am. Chem. Soc., 131 [17] 6050-51 (2009).   DOI
76 S. S. Shin, W. S. Yang, E. J. Yeom, S. J. Lee, N. J. Jeon, Y. C. Joo, I. J. Park, J. H. Noh, and S. I. Seok, "Tailoring of Electron-Collecting Oxide Nanoparticulate Layer for Flexible Perovskite Solar Cells," J. Phys. Chem. Lett., 7 [10] 1845-51 (2016).   DOI
77 J. Zhou, X. Meng, X. Zhang, X. Tao, Z. Zhang, J. Hu, C. Wang, Y. Li, and S. Yang, "Low-Temperature Aqueous Solution Processed ZnO as an Electron Transporting Layer For Efficient Perovskite Solar Cells," Mater. Chem. Front., 1 [5] 802-6 (2017).   DOI
78 S. S. Shin, W. S. Yang, E. J. Yeom, S. J. Lee, N. J. Jeon, Y.-C. Joo, I. J. Park, J. H. Noh, and S. I. Seok, "Tailoring of Electron-Collecting Oxide Nanoparticulate Layer for Flexible Perovskite Solar Cells," J. Phys. Chem. Lett., 7 [10] 1845-51 (2016).   DOI