本論文主要在探討極性溶劑對於電洞傳輸層PEDOT:PSS之影響，我們藉由設計溶劑沖洗(solvent washing)的實驗方法，發現這些個別溶劑會改變元件的電性參數，並以許多量測方法驗證極性溶劑二甲基亞碸會使PEDOT:PSS的參雜比例發生改變。因此當我們使用混合極性溶劑配置鈣鈦礦前驅物溶液時，會觀察到前驅物溶液長時間停留在電洞傳輸層PEDOT:PSS上的影響和溶劑二甲基亞碸所改變元件電性的趨勢一樣。為了改善極性溶劑對電洞傳輸層的影響，最後我們成功以氧化鎳NiOx成功取代PEDOT:PSS，不僅能提升元件效率，且不會被極性溶劑改變元件電性表現。

Perovskite solar cells (PSCs) have attracted considerable attention because of their low fabrication cost and impressive energy conversion efficiency. Since perovskite precursor solution is typically prepared from polar solvents, understanding the effect of polar solvents treatment of the PEDOT:PSS layer on the performance of perovskite solar cells is important for device processing optimization. Here, influence of the surface treatment of the PEDOT:PSS layer with solvents, including dimethyl sulfoxide (DMSO), and γ-butyrolactone (GBL), on the device performance of the perovskite solar cells was investigated. Increased conductivity was measured for the PEDOT:PSS film after solvent treatments, which was ascribed to the partial removal of PSS component from the PEDOT:PSS layer, as evidenced by the photoluminescence spectroscopy, UV-vis absorption spectroscopy and XPS spectroscopy. In comparison with the reference cell, poorer device performance was obtained for the perovskite solar cells directly deposited on the solvent washed PEDOT:PSS film. Finally, PEDOT:PSS was replaced by NiOx as a hole transport layer, successfully frabricating the device won’t be affected by polar solvents.

[1] W. G. Adams, R. Day, “The action of light on selenium”, Proc. R. Soc. London, 25, 113-117 (1876).
[2] D. M. Chapin, C. S. Fuller, G. L. Pearson, “A new silicon p‐n junction photocell for converting solar radiation into electrical power”, J. Appl. Phys. 25, 676-677 (1954).
[3] http://www.nrel.gov/ncpv/images/efficiency_chart.jpg (National Renewable Energy Laboratory, NREAL, accessed 27 June 2017).
[4] N. Jain, M. K. Hudait, “Design for metamorphic dual junction InGaP GaAs solar cell on Si with efficiency greater than 29 % using finite element analysis”, 28th IEEE Photovoltaic Spec. Conf. 2056-2060 (2012).
[5] J. P. Ponson, “A review of ohmic and rectifying contacts on cadmium telluride”, Solid-State Electronics 28, 689-706 (1985).
[6] B. O’regan, M. Grätzel, “A low cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films”, Nature 353, 737-740 (1991).
[7] J. C. Frankel, “Newcomer juices up the race to harness sunlight”, Science 342, 1438-1439 (2013).
[8] 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, T. M. Brown, “Flexible perovskite photovoltaic modules and solar cells based on atomic layer deposited compact layers and UV-Irradiated TiO2 scaffolds on plastic substrates”, Adv. Energy Mater. 5, 1401808 (2015).
[9] F. Matteocci, L. Cinà, F. D. Giacomo, S. Razza, A. L. Palma, A. Guidobaldi, A. D'Epifanio, S. Licoccia, T. M. Brown, A. Reale, A. D. Carlo, “High efficiency photovoltaic module based on mesoscopic organometal halide perovskite”, Prog. Photovolt: Res. Appl. 24, 436-445 (2016).
[10] S. -J. Moon, J. -H. Yum, L. L¨ofgren, A. Walter, L. Sansonnens, M. Benkhaira, S. Nicolay, J. Bailat, C. Ballif, “Laser-scribing patterning for the production of organometallic halide perovskite solar modules”, IEEE J. Photovolt. 5, 1087-1092 (2015).
[11] S. Razza, F. D. Giacomo, F. Matteocci, L. Cinà, A. L. Palma, S. Casaluci, P. Cameron, A. D'Epifanio, S. Licoccia, A. Reale, T. M. Brown, A. D. Carlo, “Perovskite solar cells and large area modules (100 cm2) based on an air flow-assisted PbI2 blade coating deposition process”, J. Power Sources 277, 286-291 (2015).
[12] F. Matteocci, S. Casaluci, S. Razza, A. Guidobaldi, T. M. Brown, A. Reale, A. D. Carlo, “Solid state dye solar cell modules”, J. Power Sources 246, 361-364 (2014).
[13] Y. Galagan, E. W. C. Coenen, W. J. H. Verheesc, R. Andriessena, “Towards the scaling up of perovskite solar cells and modules”, J. Mater. Chem. A 4, 5700-5705 (2016).
[14] J. Seo, S. Park, Y. C. Kim, N. J. Jeon, J. H. Noh, S. C. Yoon, S. I. Seok, “Benefits of very thin PCBM and LiF layers for solution-processed p-i-n perovskite solar cells”, Energy Environ. Sci. 7, 2642 (2014).
[15] S. Bai, Y. Jin, F. Gao, “Organometal halide perovskites for photovoltaic applications”, Adv. Funct. Mater. (eds A. Tiwari and L. Uzun), John Wiley & Sons, Inc., Hoboken, NJ, USA, 535-566 (2015).
[16] H. -S. Kim, S. -H. Im, N. -G. Park, “Organolead halide perovskite: new horizons in solar cell research”, J. Phy. Chem. C 118, 5615-5625 (2014).
[17] M. A. Green, A. Ho-Baillie, H. J. Snaith, “The emergence of perovskite solar cells”, Nat. Photonics 8, 506-514 (2014).
[18] K. Tanaka, T. Takahashi, T. Ban, T. Kondo, K. Uchida, N. Miura, “Comparative study on the excitons in lead-halide-based perovskite-type crystals CH3NH3PbBr3 CH3NH3PbI3”, Solid State Commun. 127, 619-623 (2003).
[19] S. R. Forrest, “The limits to organic photovoltaic cell efficiency”, MRS Bulletin 30, 28-32 (2005).
[20] N. S. Sariciftci, L. Smilowitz, A. J. Heeger, F. Wudl, “Photoinduced electron transfer from a conducting polymer to buckminsterfullerene”, Science 258, 1474-1476 (1992).
[21] P. W. Atkins, “Kurzlehrbuch physikalische Chemie”, Wiley-VCH , Germany, (2001).
[22] V. Shrotriya, G. Li, Y. Yao, T. Moriarty, K. Emery, Y. Yang, “Accurate measurement and characterization of organic solar cells”, Adv. Funct. Mater. 16, 2016-2023 (2006).
[23] A. Moliton, J. -M. Nunzi, “How to model the behavior of organic photovoltaic cells”, Polym. Int. 55, 583-600 (2006).
[24] C. Waldauf, M. C. Scharber, P. Schilinsky, J. A. Hauch, C. J. Brabec, “Physics of organic bulk heterojunction devices for photovoltaic applications”, J. Appl. Phys. 99, 104503-104508 (2006).
[25] A. Kojima, K. Teshima, Y. Shirai, T. Miyasaka, “Organometal halide perovskites as visible-light sensitizers for photovoltaic cells”, J. Am. Chem. Soc. 131, 6050-6051 (2009).
[26] J. -H. Im, C. -R. Lee, J. -W. Lee, S. -W. Park, N. -G. Park, “6.5% efficient perovskite quantum-dot-sensitized solar cell”, Nanoscale 3, 4088-4093 (2011).
[27] J. Burschka, A. Dualeh, F. Kessler, E. Baranoff, N. -L. Cevey-Ha, C. Yi, M. K. Nazeeruddin, M. Grätzel, “Tris(2-(1H-pyrazol-1-yl)pyridine)cobalt(III) as p-type dopant for organic semiconductors and its application in highly efficient solid-state dye-sensitized solar cells”, J. Am. Chem. Soc. 133, 18042-18045 (2011).
[28] I. Chung, B. Lee, J. He, R. P. H. Chang, M. G. Kanatzidis, “All-solid-state dye-sensitized solar cells with high efficiency”, Nature 485, 486-489 (2012).
[29] 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. Grätzel, 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).
[30] M. M. Lee, J. Teuscher, T. Miyasaka, T. N. Murakami, H. J. Snaith, “Efficient hybrid solar cells based on meso-superstructured organometal halide perovskites”, Science 338, 643-647 (2012).
[31] O. Malinkiewicz, A. Yella, Y. H. Lee, G. M. Espallargas, M. Grätzel, M. K. Nazeeruddin, H. J. Bolink, “Perovskite solar cells employing organic charge-transport layers”, Nat. Photonics 8, 128-132 (2014).
[32] L. Etgar, P. Gao, Z. Xue, Q. Peng, A. K. Chandiran, B. Liu, M. K. Nazeeruddin, M. Grätzel, “Mesoscopic CH3NH3PbI3/TiO2 heterojunction solar cells”, J. Am. Chem. Soc. 134, 17396-17399 (2012).
[33] J. -H. Heo, S. -H. Im, J. -H. Noh, T. N. Mandal, C. -S. Lim, J. -A. Chang, Y. -H. Lee, H. -J. Kim, A. Sarkar, M. K. Nazeeruddin, M. Grätzel, S. -I. Seok, “Efficient inorganic-organic hybrid heterojunction solar cells containing compound and polymeric hole conductors”, Nat. Photonics 7, 486-491 (2013).
[34] J. -Y. Jeng, Y. -F. Chiang, M. -H. Lee, S. -R. Peng, T. -F. Guo, P. Chen, T. -C. Wen, “CH3NH3PbI3 perovskite/fullerene planar-heterojunction hybrid solar cells”, Adv. Mater. 25, 3727-3732 (2013).
[35] J. Burschka, N. Pellet, S. -J. Moon, R. Humphry-Baker, P. Gao, M. K. Nazeeruddin, M. Grätzel, “Sequential deposition as a route to high-performance perovskite-sensitized solar cells”, Nature 499, 316-319 (2013).
[36] M. Liu, M. B. Johnston, H. J. Snaith, “Efficient planar heterojunction perovskite solar cells by vapor deposition”, Nature 501, 395-398 (2013).
[37] H. Zhou, Q. Chen, G. Li, S. Luo, T. -b. Song, H. -S. Duan, Z. Hong, J. You, Y. Liu, Y. Yang, “Interface engineering of highly efficient perovskite solar cells”, Science 345, 542-546 (2014).
[38] D. Bi, C. Yi, J. Luo, J. -D. Décoppet, F. Zhang, S. M. Zakeeruddin, X. Li, A. Hagfeldt, M. Grätzel, “Polymer-templated nucleation and crystal growth of perovskite films for solar cells with efficiency greater than 21%”, Nature Energy 1, 16142 (2016).
[39] D. Bi, W. Tress, M. I. Dar, P. Gao, J. Luo, C. Renevier, K. Schenk, A. Abate, F. Giordano, J. -P. C. Baena, J. -D. Decoppet, S. M. Zakeeruddin, M. K. Nazeeruddin, M. Grätzel, A. Hagfeldt, “Efficient luminescent solar cells based on tailored mixed-cation perovskites”, Science Advances 2, e1501170 (2016).
[40] Q. Wang, Y. Shao, Q. Dong, Z. Xiao, Y. Yuan, J. Huang, “Large fill-factor bilayer iodine perovskite solar cells fabricated by a low-temperature solution-process”, Energy Environ. Sci. 7, 2359-2365 (2014).
[41] G. Hodes, “Perovskite-based solar cells”, Science 342, 317-318 (2013).
[42] G. E. Eperon, V. M. Burlakov, P. Docampo, A. Goriely, H. J. Snaith, “Morphological control for high performance, solution-processed planar heterojunction perovskite solar cells”, Adv. Funct. Mater. 24, 151-157 (2014).
[43] R. F. Service, “Turning up the light”, Science 342, 794-797 (2013).
[44] N. J. Jeon, J. H. Noh, Y. C. Kim, W. S. Yang, S. Ryu, S. I. Seok, “Solvent engineering for high-performance inorganic-organic hybrid perovskite solar cells”, Nat. Mater. 13, 897-903 (2014).
[45] M. Xiao, F. Huang, W. Huang, Y. Dkhissi, Y. Zhu, J. Etheridge, A. Gray-Weale, U. Bach, Y. -B. Cheng, L. Spiccia, “A fast deposition-crystallization procedure for highly efficient lead iodide perovskite thin-film solar cells”, Angew. Chem. 126, 10056-10061 (2014).
[46] M. Nam, M. Cha, H. H. Lee, K. Hur, K. -T. Lee, J. Yoo, I. K. Han, S. J. Kwon, D. -H. Ko, “Long-term efficient organic photovoltaics based on quaternary bulk heterojunctions”, Nat. Commun. 8, 14068 (2017).
[47] J. Peet, J. Y. Kim, N. E. Coates, W. L. Ma, D. Moses, A. J. Heeger, G. C. Bazan, “Efficiency enhancement in low-bandgap polymer solar cells by processing with alkane dithiols”, Nat. Mater. 6, 497-500 (2007).
[48] Y. Sun, G. C. Welch, W. L. Leong, C. J. Takacs, G. C. Bazan, A. J. Heeger, “Solution-processed small-molecule solar cells with 6.7% efficiency”, Nat. Mater. 11, 44-48 (2012).
[49] Y. Deng, E. Peng, Y. Shao, Z. Xiao, Q. Dong, J. Huang, “Scalable fabrication of efficient organolead trihalide perovskite solar cells with doctor-bladed active layers”, Energy Environ. Sci. 8, 1544-1550 (2015).
[50] K. Hwang, Y. -S. Jung, Y. -J. Heo, F. H. Scholes, S. E. Watkins, J. Subbiah, D. J. Jones, D. -Y. Kim, D. Vak, “Toward large scale roll-to-roll production of fully printed perovskite solar cells”, Adv. Mater. 27, 1241-1247 (2015).
[51] C. -C. Chueh, C. -Y. Liao, F. Zuo, S. T. Williams, P. -W. Lianga, A. K. -Y. Jen, “The roles of alkyl halide additives in enhancing perovskite solar cell performance”, J. Mater. Chem. A 3, 9058-9062 (2015).
[52] P. -W. Liang, C. -Y. Liao, C. -C. Chueh, F. Zuo, S. T. Williams, X. -K. Xin, J. Lin, A. K. -Y. Jen, “Additive enhanced crystallization of solution-processed perovskite for highly efficient planar-heterojunction solar cells”, Adv. Mater. 26, 3748-3754 (2014).
[53] G. E. Eperon, S. D. Stranks, C. Menelaou, M. B. Johnston, L. M. Herz, H. J. Snaith, “Formamidinium lead trihalide: a broadly tunable perovskite for efficient planar heterojunction solar cells”, Energy Environ. Sci. 7, 982-988 (2014).
[54] F. Wang, H. Yu, H. Xu, N. Zhao, “HPbI3: A new precursor compound for highly efficient solution-processed perovskite solar cells”, Adv. Funct. Mater. 7, 1120-1126 (2015).
[55] J. H. Heo, D. H. Song, H. J. Han, S. Y. Kim, J. H. Kim, D. Kim, H. W. Shin, T. K. Ahn, C. Wolf, T. -W. Lee, S. H. Im, “Planar CH3NH3PbI3 perovskite solar cells with constant 17.2% average power conversion efficiency irrespective of the scan rate”, Adv. Mater. 27, 3424-3430 (2015).
[56] H. -B. Kim, H. Choi, J. Jeong, S. Kim, B. Walker, S. Song, J. Y. Kim, “Mixed solvents for the optimization of morphology in solution-processed, inverted-type perovskite/fullerene hybrid solar cells”, Nanoscale 6, 6679-6683 (2014).
[57] Y. -J. Jeon, S. Lee, R. Kang, J. -E. Kim, J. -S. Yeo, S. -H. Lee, S. -S. Kim, J. -M. Yun, D. -Y. Kim, “Planar heterojunction perovskite solar cells with superior reproducibility”, Sci. Rep. 4, 6953 (2014).
[58] C. -Y. Chang, C. -Y. Chu, Y. -C. Huang, C. -W. Huang, S. -Y. Chang, C. -A. Chen, C. -Y. Chao, W. -F. Su, “Tuning perovskite morphology by polymer additive for high efficiency solar cell”, ACS Appl. Mater. Interfaces 7, 4955-4961 (2015).
[59] W. Zhang, M. Saliba, D. T. Moore, S. K. Pathak, M. T. Hörantner, T. Stergiopoulos, S. D. Stranks, G. E. Eperon, J. A. Alexander-Webber, A. Abate, A. Sadhanala, S. Yao, Y. Chen, R. H. Friend, L. A. Estroff, U. Wiesner, H. J. Snaith, “Ultrasmooth organic-inorganic perovskite thin-film formation and crystallization for efficient planar heterojunction solar cells”, Nat. Commun. 6, 6124 (2015).
[60] G. Xing, N. Mathews, S. Sun, S. S. Lim, Y. M. Lam, M. Grätzel, S. Mhaisalkar, T. C. Sum, “Long-range balanced electron- and hole-transport lengths in organic-inorganic CH3NH3PbI3”, Science 342, 344-347 (2013).
[61] L. Zuo, Z. Gu, T. Ye, W. Fu, G. Wu, H. Li, H. Chen, “Enhanced photovoltaic performance of CH3NH3PbI3 perovskite solar cells through interfacial engineering using self-assembling monolayer”, J. Am. Chem. Soc. 7, 2674-2679 (2015).
[62] Y. Ogomi, A. Morita, S. Tsukamoto, T. Saitho, Q. Shen, T. Toyoda, K. Yoshino, S. S. Pandey, T. Ma, S. Hayase, “All-solid perovskite solar cells with HOCO-R-NH3+I– anchor-group inserted between porous titania and perovskite”, J. Phys. Chem. C 118, 16651-16659 (2014).
[63] W. Nie, 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, A. D. Mohite, “High-efficiency solution-processed perovskite solar cells with millimeter-scale grains”, Science 347, 522-525 (2015).
[64] Z. Xiao, C. Bi, Y. Shao, Q. Dong, Q. Wang, Y. Yuan, C. Wang, Y. Gaobc, J. Huang, “Efficient, high yield perovskite photovoltaic devices grown by interdiffusion of solution-processed precursor stacking layers”, Energy Environ. Sci. 7, 2619-2623 (2014).
[65] Q. Chen, H. Zhou, Z. Hong, S. Luo, H. -S. Duan, H. -H. Wang, Y. Liu, G. Li, Y. Yang, “Planar heterojunction perovskite solar cells via vapor-assisted solution process”, J. Am. Chem. Soc. 136, 622-625 (2014).
[66] Q. Chen, H. Zhou, T. -B. Song, S. Luo, Z. Hong, H. -S. Duan, L. Dou, Y. Liu, Y. Yang, “Controllable self-induced passivation of hybrid lead iodide perovskites toward high performance solar cells”, Nano Lett. 14, 4158-4163 (2014).
[67] G. Li, V. Shrotriya, J. Huang, Y. Yao, T. Moriarty, K. Emery, Y. Yang, “High-efficiency solution processable polymer photovoltaic cells by self-organization of polymer blends”, Nat. Mater. 4, 864-868 (2005).
[68] G. Li, R. Zhu, Y. Yang, “Polymer solar cells”, Nat. Photonics 6, 153-161 (2012).
[69] Z. Xiao, Q. Dong, C. Bi, Y. Shao, Y. Yuan, J. Huang, “Solvent annealing of perovskite-induced crystal growth for photovoltaic-device efficiency enhancement”, Adv. Mater. 26, 6503-6509 (2014).
[70] Z. Zhou, Z. Wang, Y. Zhou, S. Pang, D. Wang, H. Xu, Z. Liu, N. P. Padture, G. Cui, “Methylamine-gas-induced defect-healing behavior of CH3NH3PbI3 thin films for perovskite solar cells”, Angew. Chem. Int. Ed. 54, 9705-9709 (2015).
[71] H. J. Ahonen, J. Lukkari, J. Kankare, “n- and p-doped poly(3,4-ethylenedioxythiophene):  two electronically conducting states of the polymer”, Macromolecules 33, 6787-6793 (2000).
[72] H. W. Heuer, R. Wehrmann, S. Kirchmeyer, “Electrochromic window based on conducting poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate)”, Adv. Funct. Mater. 12, 89-94 (2002).
[73] Y. Furukawa, “Electronic absorption and vibrational spectroscopies of conjugated conducting polymers”, J. Phys. Chem. 100, 15644-15653 (1996).
[74] Y. Wang, “Research progress on a novel conductive polymer-poly(3,4-ethylenedioxythiophene) (PEDOT)”, J. Phys.: Conf. Ser. 152, 012023 (2009).
[75] E. A. Bazzaoui, G. Levi, S. Aeiyach, J. Aubard, J. P. Marsault, P. C. Lacaze, “SERS Spectra of Polythiophene in Doped and Undoped States”, J. Phys. Chem. 99, 6628-6634 (1995).
[76] A. V. Kubarkov, O. A. Pyshkina, V. G. Sergeyev, “Synthesis and physicochemical properties of copolymers of aniline and 3,4-ethylenedioxythiophene”, Polym. Sci. Ser. B 56, 360-368 (2014).
[77] S. Garreau, G. Louarn, J. P. Buisson, G. Froyer, S. Lefrant, “In Situ Spectroelectrochemical raman studies of poly(3,4-ethylenedioxythiophene) (PEDT)”, Macromolecules 32, 6807-6812 (1999).
[78] H. Yamato, M. Ohwa, W. Wernet, “Stability of polypyrrole and poly(3,4-ethylenedioxythiophene) for biosensor application”, J. Electroanal. Chem. 397, 163-170 (1995).
[79] Y. Xia, K. Sun, J. Ouyang, “Solution-Processed Metallic Conducting Polymer Films as Transparent Electrode of Optoelectronic Devices”, Adv. Mater. 24, 2436-2440 (2012).
[80] D. Alemu, H. -Y. Wei, K. -C. Ho, C. -W. Chu, “Highly conductive PEDOT:PSS electrode by simple film treatment with methanol for ITO-free polymer solar cells”, Energy Environ. Sci. 5, 9662-9671 (2012).
[81] J. Y. Kim, J. H. Jung, D. E. Lee, “Enhancement of electrical conductivity of poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) by a change of solvents”, Synth. Met. 126, 311-316 (2002).
[82] C. Bi, Q. Wang, Y. Shao, Y. Yuan, Z. Xiao, J. Huang, “Non-wetting surface-driven high-aspect-ratio crystalline grain growth for efficient hybrid perovskite solar cells”, Nat. Commun. 6, 7747 (2015).
[83] M. P. de Jong, L. J. van IJzendoorn, M. J. A. de Voigt, “Stability of the interface between indium-tin-oxide and poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) in polymer light-emitting diodes”, Appl. Phys. Lett. 77, 2255 (2000).
[84] D. T. Moore, H. Sai, K. W. Tan, L. A. Estroff, U. Wiesner, “Impact of the organic halide salt on final perovskite composition for photovoltaic applications”, APL Mater. 2, 081802 (2014).
[85] Y. -K. Chih, J. -C. Wang, R. -T. Yang, C. -C. Liu, Y. -C. Chang, Y. -S. Fu, W. -C. Lai, P. Chen, T. -C. Wen, Y. -C. Huang, C. -S. Tsao, T. -F. Guo, “NiOx Electrode Interlayer and CH3NH2/CH3NH3PbBr3 Interface Treatment to Markedly Advance Hybrid Perovskite-Based Light-Emitting Diodes”, Adv. Mater. 28, 8687-8694 (2016).