本研究探討以聚丙烯晴(Polyacrylonitrile, PAN)和聚甲基丙烯酸甲酯(Poly(methyl methacrylate), PMMA)，依不同混摻比例製備而成的電紡絲高分子奈米纖維，其性質及於鋁離子電池之應用。調整高分子在二甲基甲醯胺(N,N-dimethylformamide, DMF)中的濃度以及高分子混合比例(PAN:PMMA= 100:0, 75:25, 50:50, 25:75)，製備平均直徑落在300-500 nm的奈米纖維膜。表面型態由SEM觀察得知，以靜電紡絲法製備成奈米纖維隔離膜，其纖維皆呈現完整結構且均勻分布，交錯之纖維結構產生自然孔隙有助離離子於電池中的移動。熱性質利用TGA及DSC分析，奈米纖維膜在300℃以下保持穩定狀態，無裂解或結晶等現象發生。纖維組成分析則以FTIR鑑定，加入PMMA後其特性峰C＝O 、C—O出現，並且C=O吸收峰隨PMMA比例提升而增強。X光繞射圖譜則說明奈米纖維膜的結晶特性，經靜電紡絲法製備成的纖維，結晶度下降，非定型區域則可有效吸收電解質，是為電池隔離膜之良好材料。另外，孔洞分析則利用BET法，隨著PMMA比例上升，比表面積也有略微上升的現象。奈米纖維膜實際應用於鋁離子電池時，電解液相容性良好，並且對電解液有500~1000% 的吸收量，可使電池運作穩定。離子傳導度測試顯示在30~70℃溫度區間內，有隨溫度上升而提高的趨勢，並且數值大約保持在1~3 mS·cm-1。充放電以變電流密度50、100、200、400 mA·g-1測試，比電容量有隨電流密度提高而下降的趨勢。長效分析以100 mA·g-1進行測試。依據實驗結果，以電池放電電容作為比較依據，PAN:PMMA=50:50奈米纖維膜有最佳電容表現；若根據電池壽命圈數判定，則PAN:PMMA=75:25奈米纖維膜具有最長壽命，並且數據皆優於商用隔離膜所使用材料玻璃纖維。

In this study, we produce electrospun nanofibers (ENs) of two polymers polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) used as separators for rechargeable aluminum batteries. By manipulating the concentration (10, 12, 14 and 18 wt%) of polymer in N,N-dimethylformamide (DMF) and different PAN/PMMA blend ratios (100:0, 75:25, 50:50, 25:75), we successfully prepare separators compatible with highly reactive 1-ethyl-3-methylimidazolium chloride:aluminum trichloride (EMIMCl:AlCl3) electrolyte employed in aluminum-ion batteries. The developed separators are characterized in terms of morphology, thermal properties, porosity, crystallinity, and ionic conductivity, also showing a good wettability in the electrolyte. Furthermore, the cells fabricated with the polymer membranes reveal remarkably good rate performance and cycling behavior. The results confirm PAN/PMMA separators as promising candidates for rechargeable aluminum-ion batteries (RABs).

[1] Huicong Yang, Hucheng Li, Juan Li, Zhenhua Sun, Kuang He, Hui-Ming Cheng, and Feng Li, The Rechargeable Aluminum Battery: Opportunities and Challenges. Angewandte Chemie International Edition, 2019.
[2] Zhijing Yu, Shuqiang Jiao, Shijie Li, Xiaodong Chen, Wei‐Li Song, Teng Teng, Jiguo Tu, Hao‐Sen Chen, Guohua Zhang, and Dai‐Ning Fang, Flexible Stable Solid‐State Al‐Ion Batteries. Advanced Functional Materials, 29, 1, 1806799, 2019.
[3] Shyamal K. Das, Sadhan Mahapatra, and Homen Lahan, Aluminium-ion batteries: developments and challenges. Journal of Materials Chemistry A, 5, 14, 6347-6367, 2017.
[4] D. Y. Wang, C. Y. Wei, M. C. Lin, C. J. Pan, H. L. Chou, H. A. Chen, M. Gong, Y. Wu, C. Yuan, M. Angell, Y. J. Hsieh, Y. H. Chen, C. Y. Wen, C. W. Chen, B. J. Hwang, C. C. Chen, and H. Dai, Advanced rechargeable aluminium ion battery with a high-quality natural graphite cathode. Nat Commun, 8, 14283, 2017.
[5] Meng-Chang Lin, Ming Gong, Bingan Lu, Yingpeng Wu, Di-Yan Wang, Mingyun Guan, Michael Angell, Changxin Chen, Jiang Yang, and Bing-Joe Hwang, An ultrafast rechargeable aluminium-ion battery. Nature, 520, 7547, 324, 2015.
[6] Gerhard L Holleck and José Giner, The Aluminum Electrode in AlCl3‐Alkali‐Halide Melts. Journal of the Electrochemical Society, 119, 9, 1161-1166, 1972.
[7] N Koura, A preliminary investigation for an Al/AlCl3-NaCl/FeS2 secondary cell. Journal of The Electrochemical Society, 127, 1529-1531, 1980.
[8] Handong Jiao, Junxiang Wang, Jiguo Tu, Haiping Lei, and Shuqiang Jiao, Aluminum-Ion Asymmetric Supercapacitor Incorporating Carbon Nanotubes and an Ionic Liquid Electrolyte: Al/AlCl3-[EMIm]Cl/CNTs. Energy Technology, 4, 9, 1112-1118, 2016.
[9] Giuseppe Antonio Elia, Krystan Marquardt, Katrin Hoeppner, Sebastien Fantini, Rongying Lin, Etienne Knipping, Willi Peters, Jean‐Francois Drillet, Stefano Passerini, and Robert Hahn, An overview and future perspectives of aluminum batteries. Advanced Materials, 28, 35, 7564-7579, 2016.
[10] Haobo Sun, Wei Wang, Zhijing Yu, Yan Yuan, Shuai Wang, and Shuqiang Jiao, A new aluminium-ion battery with high voltage, high safety and low cost. Chemical Communications, 51, 59, 11892-11895, 2015.
[11] Y. Zhang, S. Liu, Y. Ji, J. Ma, and H. Yu, Emerging Nonaqueous Aluminum-Ion Batteries: Challenges, Status, and Perspectives. Adv Mater, 30, 38, e1706310, 2018.
[12] H. Wang, Y. Bai, S. Chen, X. Luo, C. Wu, F. Wu, J. Lu, and K. Amine, Binder-free V2O5 cathode for greener rechargeable aluminum battery. ACS Appl Mater Interfaces, 7, 1, 80-4, 2015.
[13] N. Jayaprakash, S. K. Das, and L. A. Archer, The rechargeable aluminum-ion battery. Chem Commun (Camb), 47, 47, 12610-2, 2011.
[14] W. Wang, B. Jiang, W. Xiong, H. Sun, Z. Lin, L. Hu, J. Tu, J. Hou, H. Zhu, and S. Jiao, A new cathode material for super-valent battery based on aluminium ion intercalation and deintercalation. Sci Rep, 3, 3383, 2013.
[15] Dipayan Pal, Aakash Mathur, Ajaib Singh, Srimanta Pakhira, Rinki Singh, and Sudeshna Chattopadhyay, Binder-Free ZnO Cathode synthesized via ALD by Direct Growth of Hierarchical ZnO Nanostructure on Current Collector for High-Performance Rechargeable Aluminium-Ion Batteries. ChemistrySelect, 3, 44, 12512-12523, 2018.
[16] Linxiao Geng, Guocheng Lv, Xuebing Xing, and Juchen Guo, Reversible Electrochemical Intercalation of Aluminum in Mo6S8. Chemistry of Materials, 27, 14, 4926-4929, 2015.
[17] Z. Li, B. Niu, J. Liu, J. Li, and F. Kang, Rechargeable Aluminum-Ion Battery Based on MoS2 Microsphere Cathode. ACS Appl Mater Interfaces, 10, 11, 9451-9459, 2018.
[18] Y. Hu, D. Ye, B. Luo, H. Hu, X. Zhu, S. Wang, L. Li, S. Peng, and L. Wang, A Binder-Free and Free-Standing Cobalt Sulfide@Carbon Nanotube Cathode Material for Aluminum-Ion Batteries. Adv Mater, 30, 2, 2018.
[19] Hucheng Li, Huicong Yang, Zhenhua Sun, Ying Shi, Hui-Ming Cheng, and Feng Li, A highly reversible Co3S4 microsphere cathode material for aluminum-ion batteries. Nano Energy, 56, 100-108, 2019.
[20] Ying Juan He, Jun Fang Peng, Wei Chu, Yuan Zhi Li, and Dong Ge Tong, Black mesoporous anatase TiO2 nanoleaves: a high capacity and high rate anode for aqueous Al-ion batteries. Journal of Materials Chemistry A, 2, 6, 1721-1731, 2014.
[21] Alexander Holland, RD Mckerracher, Andrew Cruden, and RGA Wills, An aluminium battery operating with an aqueous electrolyte. Journal of Applied Electrochemistry, 48, 3, 243-250, 2018.
[22] Mahdi Kazazi, Pedram Abdollahi, and Mahdi Mirzaei-Moghadam, High surface area TiO2 nanospheres as a high-rate anode material for aqueous aluminium-ion batteries. Solid State Ionics, 300, 32-37, 2017.
[23] S. Choi, H. Go, G. Lee, and Y. Tak, Electrochemical properties of an aluminum anode in an ionic liquid electrolyte for rechargeable aluminum-ion batteries. Phys Chem Chem Phys, 19, 13, 8653-8656, 2017.
[24] S Liu, GL Pan, GR Li, and XP Gao, Copper hexacyanoferrate nanoparticles as cathode material for aqueous Al-ion batteries. Journal of Materials Chemistry A, 3, 3, 959-962, 2015.
[25] Betty S Del Duca, Electrochemical Behavior of the Aluminum Electrode in Molten Salt Electrolytes. Journal of The Electrochemical Society, 118, 3, 405-411, 1971.
[26] X. G. Sun, Y. Fang, X. Jiang, K. Yoshii, T. Tsuda, and S. Dai, Polymer gel electrolytes for application in aluminum deposition and rechargeable aluminum ion batteries. Chem Commun (Camb), 52, 2, 292-5, 2016.
[27] N Maragani and K Vijaya Kumar, Structural and Conductivity Studies of PAN-based Al2O3 Nano Composite Gel Polymer Electrolytes. Iranian Journal of Materials Science and Engineering, 15, 4, 11-18, 2018.
[28] Kai Wei, Kyu-Oh Kim, Kyung-Hun Song, Chang-Yong Kang, Jung Soon Lee, Mayakrishnan Gopiraman, and Ick-Soo Kim, Nitrogen- and Oxygen-Containing Porous Ultrafine Carbon Nanofiber: A Highly Flexible Electrode Material for Supercapacitor. Journal of Materials Science & Technology, 33, 5, 424-431, 2017.
[29] Tianyi Yao, Francielli S. Genier, Saeid Biria, and Ian D. Hosein, A solid polymer electrolyte for aluminum ion conduction. Results in Physics, 10, 529-531, 2018.
[30] Lord Rayleigh, XX. On the equilibrium of liquid conducting masses charged with electricity. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 14, 87, 184-186, 1882.
[31] John Zeleny, Instability of electrified liquid surfaces. Physical review, 10, 1, 1, 1917.
[32] Geoffrey Ingram Taylor, Electrically driven jets. Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 313, 1515, 453-475, 1969.
[33] Formhals Anton, Artificial thread and method of producing same, 1940, Google Patents.
[34] Formhals Anton, Method and apparatus for spinning, 1939, Google Patents.
[35] Formhals Anton, Process and apparatus for preparing artificial threads, 1934, Google Patents.
[36] Ji-Won Jung, Cho-Long Lee, Sunmoon Yu, and Il-Doo Kim, Electrospun nanofibers as a platform for advanced secondary batteries: a comprehensive review. Journal of materials chemistry A, 4, 3, 703-750, 2016.
[37] Avinash Baji, Yiu-Wing Mai, Shing-Chung Wong, Mojtaba Abtahi, and Pei Chen, Electrospinning of polymer nanofibers: effects on oriented morphology, structures and tensile properties. Composites science and technology, 70, 5, 703-718, 2010.
[38] Demetrius S Gomes, Ana NR da Silva, Nilton I Morimoto, Luiz TF Mendes, Rogerio Furlan, and Idalia Ramos, Characterization of an electrospinning process using different PAN/DMF concentrations. Polímeros, 17, 3, 206-211, 2007.
[39] Shahar Kedem, Judith Schmidt, Yaron Paz, and Yachin Cohen, Composite polymer nanofibers with carbon nanotubes and titanium dioxide particles. Langmuir, 21, 12, 5600-5604, 2005.
[40] Xinhua Zong, Kwangsok Kim, Dufei Fang, Shaofeng Ran, Benjamin S Hsiao, and Benjamin Chu, Structure and process relationship of electrospun bioabsorbable nanofiber membranes. Polymer, 43, 16, 4403-4412, 2002.
[41] Tong Wang and Satish Kumar, Electrospinning of polyacrylonitrile nanofibers. Journal of applied polymer science, 102, 2, 1023-1029, 2006.
[42] Amir Houshang Hekmati, Abosaeed Rashidi, Reza Ghazisaeidi, and Jean-Yves Drean, Effect of needle length, electrospinning distance, and solution concentration on morphological properties of polyamide-6 electrospun nanowebs. Textile Research Journal, 83, 14, 1452-1466, 2013.
[43] Joseph M Deitzel, James Kleinmeyer, DEA Harris, and NC Beck Tan, The effect of processing variables on the morphology of electrospun nanofibers and textiles. Polymer, 42, 1, 261-272, 2001.
[44] Dan Li and Younan Xia, Electrospinning of nanofibers: reinventing the wheel? Advanced materials, 16, 14, 1151-1170, 2004.
[45] SY Gu, J Ren, and GJ Vancso, Process optimization and empirical modeling for electrospun polyacrylonitrile (PAN) nanofiber precursor of carbon nanofibers. European polymer journal, 41, 11, 2559-2568, 2005.
[46] H Fong, I Chun, and DH Reneker, Beaded nanofibers formed during electrospinning. Polymer, 40, 16, 4585-4592, 1999.
[47] Roya M Nezarati, Michelle B Eifert, and Elizabeth Cosgriff-Hernandez, Effects of humidity and solution viscosity on electrospun fiber morphology. Tissue Engineering Part C: Methods, 19, 10, 810-819, 2013.
[48] Qing Liao, William R Pitner, Gemma Stewart, Charles L Hussey, and Gery R Stafford, Electrodeposition of aluminum from the aluminum chloride‐1‐methyl‐3‐ethylimidazolium chloride room temperature molten salt+ benzene. Journal of the Electrochemical Society, 144, 3, 936-943, 1997.
[49] Pei-Chiung Lin, I. Wen Sun, Jeng-Kuei Chang, Chung-Jui Su, and Jing-Chie Lin, Corrosion characteristics of nickel, copper, and stainless steel in a Lewis neutral chloroaluminate ionic liquid. Corrosion Science, 53, 12, 4318-4323, 2011.
[50] M. Eckert, W. Peters, and J. F. Drillet, Fast Microwave-Assisted Hydrothermal Synthesis of Pure Layered delta-MnO(2) for Multivalent Ion Intercalation. Materials (Basel), 11, 12, 2018.
[51] Stephen Brunauer, Paul Hugh Emmett, and Edward Teller, Adsorption of gases in multimolecular layers. Journal of the American chemical society, 60, 2, 309-319, 1938.
[52] Chang Kook Hong, Kap Seung Yang, Seung Hyun Oh, Jou-Hyeon Ahn, Baik-Hwan Cho, and Changwoon Nah, Effect of blend composition on the morphology development of electrospun fibres based on PAN/PMMA blends. Polymer International, 57, 12, 1357-1362, 2008.
[53] SY Gu, J Ren, and QL Wu, Preparation and structures of electrospun PAN nanofibers as a precursor of carbon nanofibers. Synthetic Metals, 155, 1, 157-161, 2005.
[54] TH Cho, T Sakai, S Tanase, K Kimura, Y Kondo, T Tarao, and M Tanaka, Electrochemical performances of polyacrylonitrile nanofiber-based nonwoven separator for lithium-ion battery. Electrochemical and solid-state letters, 10, 7, A159-A162, 2007.
[55] D. G. Yu, P. Lu, C. Branford-White, J. H. Yang, and X. Wang, Polyacrylonitrile nanofibers prepared using coaxial electrospinning with LiCl solution as sheath fluid. Nanotechnology, 22, 43, 435301, 2011.
[56] Niloufar Sabetzadeh, Ali Akbar Gharehaghaji, and Mehran Javanbakht, Porous PAN micro/nanofiber separators for enhanced lithium-ion battery performance. Solid State Ionics, 325, 251-257, 2018.
[57] C. Kim, Y. I. Jeong, B. T. Ngoc, K. S. Yang, M. Kojima, Y. A. Kim, M. Endo, and J. W. Lee, Synthesis and characterization of porous carbon nanofibers with hollow cores through the thermal treatment of electrospun copolymeric nanofiber webs. Small, 3, 1, 91-5, 2007.
[58] Kenneth SW Sing, Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity (Recommendations 1984). Pure and applied chemistry, 57, 4, 603-619, 1985.
[59] Yi-Chen Wang, Tai-Chou Lee, Jheng-Yi Lin, Jeng-Kuei Chang, and Chuan-Ming Tseng, Corrosion properties of metals in dicyanamide-based ionic liquids. Corrosion Science, 78, 81-88, 2014.
[60] Shufeng Song, Masashi Kotobuki, Feng Zheng, Qibin Li, Chaohe Xu, Yu Wang, Wei Dong Z. Li, Ning Hu, and Li Lu, Al conductive hybrid solid polymer electrolyte. Solid State Ionics, 300, 165-168, 2017.
[61] Luke D. Reed and Erik Menke, The Roles of V2O5and Stainless Steel in Rechargeable Al–Ion Batteries. Journal of The Electrochemical Society, 160, 6, A915-A917, 2013.
[62] Shuai Wang, Shuqiang Jiao, Junxiang Wang, Hao-Sen Chen, Donghua Tian, Haiping Lei, and Dai-Ning Fang, High-performance aluminum-ion battery with CuS@ C microsphere composite cathode. ACS nano, 11, 1, 469-477, 2016.
[63] Feng Wu, Na Zhu, Ying Bai, Yaning Gao, and Chuan Wu, An interface-reconstruction effect for rechargeable aluminum battery in ionic liquid electrolyte to enhance cycling performances. Green Energy & Environment, 3, 1, 71-77, 2018.
[64] Qing Zhao, Michael J Zachman, Wajdi I Al Sadat, Jingxu Zheng, Lena F Kourkoutis, and Lynden Archer, Solid electrolyte interphases for high-energy aqueous aluminum electrochemical cells. Science advances, 4, 11, eaau8131, 2018.