空氣穩定鈣鈦礦電觸媒應用於染料敏化太陽能電池對電極

Air-Stable Perovskite as Electro-catalyst for the Counter Electrode in Dye-Sensitized Solar Cells

鐘仁駿(Zhong Ren-Jun)

指導教授 ： 李君婷

國立臺灣師範大學/理學院/化學系/碩士(2021年)

https://doi.org/10.6345/NTNU202100813

摘要

本研究論文旨在通過使用易於製造的染料敏化太陽能電池作為合適的量測平台來評估空 氣穩定的電化學耐用鈣鈦礦材料。在第三章通過使用於透明層的商用 Ti-Nanooxide 塗料並且 優化光散色層的二氧化鈦塗料，來建立一個穩定、可靠、低成本且易於製造的染料敏化太陽 能電池。在不使用高溫高壓設備合成二氧化鈦奈米和微米顆粒的情況下，通過添加重量比為 50 %的二氧化鈦固體製備均勻可靠的光散射二氧化鈦塗料，該塗料由 Ti-Nanoxide/ST-41（重 量比為 2/1）和聚乙二醇（PEG，相對於 ST-41 的重量比為 25%）溶於第三丁醇/去離子水（體 積比為 9/1）的混合溶劑中。獲得高達 8.47%的電池性能並具有良好的重現性和可靠性，可用 於進一步研究鈣鈦礦電極的電催化性能。 在第四章中通過使用 100%的甲脒作為 A 位分子，摻雜 10%的碘化鍺（II）於B 位元素穩定劑並添加四烷基鹵化銨作為表面鈍化劑，成功製造出結構為發泡鎳基板/二氧化鈦/甲脒碘 化鉛鍺(NF/TiO2/FA(Pb1-xGex)I3)的空氣穩定和電化學耐用的鈣鈦礦電極。所有被不同四烷基鹵 化銨鈍化的 FA(Pb1-xGex)I3 鈣鈦礦薄膜均表現出良好的 α-FAPbI3 結晶並保持良好的熱力學穩 定性，在空氣中至少四個月沒有任何晶體分解或衰變。當表面鈍化劑的四烷基銨陽離子中烷 基取代基的長度從乙基(C2)逐漸延長至十二烷基(C12)時，我們發現四正己基銨(THA)碘化物 可提供最佳的電池性能。在 FA(Pb1-xGex)I3表面添加溴化物(THA-Br)可形成少量 FAPbBr3作為 額外的活性位點來增益 I–/I3–的氧化還原反應，然而當表面添加氯化物(THA-Cl)時，THA-Cl 的團聚使得表面鈍化效果低下以及覆蓋了電活性位點，導致 FA(Pb1-xGex)I3的電催化能力下降。 最佳的 NF/TiO2/FA(Pb1-xGex)I3/THA-Br0.5I0.5 電極對多種氧化還原介質(I–/I3–, CoII/III-phen 和CuI/II-dmp)均表現出良好的電化學耐用性和電催化能力。優化後的NF/TiO2/FA(Pb1-xGex)I3/ THA-Br0.5I0.5對電極可使其染料敏化太陽能電池在 I–/I3–系統中達到 8.50% (1 個太陽光)，而在1 klux (飛利浦 T5 燈)下可達到 22%，且均具有良好的重現性，相較於傳統的白金對電極 (9.78%)，可達其效能的 87%，顯示出空氣穩定之鈣鈦礦電極在各種電化學系統中具有無限的 應用潛力。

關鍵字

空氣穩定鈣鈦礦 ； 對電極 ； 染料敏化太陽能電池 ； 電催化劑 ； 非白金

並列摘要

In this thesis, we aimed to synthesize air-stable the electrochemically durable perovskite material via using the easily fabricated dye-sensitized solar cells as an appropriate evaluation platform. In Chapter 3, a steady, reliable, low-cost, and easily conducted fabrication platform for dye-sensitized solar cells was estabilished by using the commercial Ti-Nanoxide paste for transparent layer and the optimal TiO2 paste for light-scattering layer. Without synthesizing TiO2 nanoparticles and microparticles via using high temperature and pressure equipments, the uniform and reliable lightscattering TiO2 paste was prepared by adding 50 wt% of TiO2 solid, which was composted of TiNanoxide/ST–41 (2/1 by weight), and poly(ethylene glycol) (PEG, 25 wt% with respect to the weight of ST–41) in a mixing solvent of tert-butyl alcohol/de-ionic water (9/1 by volume). Decent cell efficiency up to 8.47% was achieved, and the perovskite electrode exhibited good reproducibility and reliability for further studies of electro-catalytic properties. In Chapter 4, air-stable and electrochemical durable perovskite electrode of NF/TiO2/ FA(Pb1xGex)I3 were successfully obtained by using 100% of formamidinium as the A-site molecule, doping 10% of germanium(II) iodide as the B-stie stabilizer, and adding tetra-alkyl-ammonium halides as the surface passivators. All the FA(Pb1-xGex)I3 perovskite films passivated by different tetraalkylammonium halides exhibted good α–FAPbI3 crystalline phase, and maintained good thermodynamic stability without any crystal decomposition or decay in air for at least 4 months. Among tetra-alkylammonium surface passivators of different alkyl chain length (from ethyl (C2) to docyl (C12)), the tetra-n-hexylammonium (THA) iodide was found to provide the optimal cell performance. The bromide passivated on the FA(Pb1-xGex)I3 surface resulted in the formation of minor FAPbBr3 as extra electro-active sites for triggering I–/I3– redox reaction, while the chloride passivated on the FA(Pb1-xGex)I3 surface caused the decrease in electro-catalytic ability of FA(Pb1xGex)I3 due to the self-aggregation of THA-Cl, inefficient surface passivation, and the blockade of the electro-active sites. The optimal NF/TiO2/FA(Pb1-xGex)I3/ THA-Br0.5I0.5 electrode exhibited good electrochemical durability and electro-catalytic ability toward multiple redox mediators (I–/I3–, CoII/III-phen, and CuI/II-dmp). The DSSC with the optimal NF/TiO2/ FA(Pb1-xGex)I3 /THA-Br0.5I0.5 counter electrode reached 8.50% at 1 sun and 22% at 1 klux (Philips T5 lamp) in I–/I3– with good reproducibility; this cell effiency was 87% to that of the Pt-based DSSC (9.78%), showing a promising potential for the applications in various electrochmical systems.

並列關鍵字

Air-stable perovskite ； Counter electrodes ； Dye-sensitized solar cells ； Electro-catalyst ； Pt-free

參考文獻

1. Braga, A. F. B.；Moreira, S. P.；Zampieri, P. R.；Bacchin, J. M. G.；Mei, P. R., New processes for the production of solar-grade polycrystalline silicon: A review. Solar Energy Materials and Solar Cells 2008, 92, 418-424.

2. Luo, D.-w.；Liu, N.；Lu, Y.-p.；Zhang, G.-l.；Li, T.-j., Removal of boron from metallurgical grade silicon by electromagnetic induction slag melting. Transactions of Nonferrous Metals Society of China 2011, 21, 1178-1184.

3. Yuge, N.；Abe, M.；Hanazawa, K.；Baba, H.；Nakamura, N.；Kato, Y.；Sakaguchi, Y.；Hiwasa, S.；Aratani, F., Purification of metallurgical-grade silicon up to solar grade. Progress in Photovoltaics: Research and Applications 2001, 9, 203-209.

4. Zheng, S.-s.；Safarian, J.；Seok, S.；Kim, S.；Merete, T.；Luo, X.-t., Elimination of phosphorus vaporizing from molten silicon at finite reduced pressure. Transactions of Nonferrous Metals Society of China 2011, 21, 697-702.

5. Khattak, C. P.；Schmid, F.；Joyce, D. B.；Smelik, E. A.；Wilkinson, M. A., Production of solar-grade silicon by refining of liquid metallurgical-grade silicon. Master thesis. National Renewable Energy Laboratory, America; 1999.