論文與專利寫作暨學術 倫理期末報告 班級 : 碩化一甲學號 :MA 姓名 : 林郡澤老師 : 黃常寧

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1 論文與專利寫作暨學術 倫理期末報告 班級 : 碩化一甲學號 :MA 姓名 : 林郡澤老師 : 黃常寧

2 About 85% of the world s energy requirements are currently satisfied by exhaustible fossil fuels that have detrimental consequences on human health and the environment 1. Moreover, the global energy demand is predicted to double by 2050.International action to achieve efficient and sustainable energy is therefore imperative. 目前世界上約 85% 的能源需求是由可耗盡的化石燃料所滿足, 但化石燃料對人類健康和環境有不利的後果 此外, 全球能源需求預測到 2050 年將會是現在的兩倍 所以可再生能源變成國際焦點 因此, 必須採取國際行動來實行可再生能源 Twenty-five years ago, O Regan and Grätzel 3 reported in Nature the landmark construction of a low-cost solar cell that could convert about 7% of the energy received from sunlight into electricity. In the past seven years, their work has inspired the production of solar cells that use compounds called perovskites 4,5 and that can have conversion efficiencies of greater than 22%. 25 年前,O Regan 和 Grätzel 在 Nature 發表了一篇低成本太陽能電池的指標性論文, 可從陽光接收的能量, 約 7% 轉換成電力 在過去七年裡, 他們的工作是啟發使用化合物在太陽能電池的製造上, 稱為 perovskites( 鈣鈦礦 ), 且能有大於 22% 的轉換效率 The basic concepts for O Regan and Grätzel s technology were borrowed from photosynthesis, a process in which sunlight is absorbed by chlorophyll molecules and converted into chemical energy. In the authors dye-sensitized solar cell (DSC), light is absorbed by ruthenium-based dye molecules that are deposited on the surface of titanium dioxide (TiO2) nanoparticles (Fig.1a). O Regan 和 Grätzel s 的技術借用了光合作用的基本概念, 葉綠素吸收陽光和轉換成化學能的過程 染料敏化太陽能電池, 是由釕基染料分子吸收光, 然後沉積在二氧化鈦奈米顆粒的表面上 At the interface between the dye and the nanoparticles, an excited electron and an associated hole (a conceptual particle formed by the absence of an electron) are produced. 在染料和奈米顆粒之間的界面處 ( 會發生載子分解 charge separation), 激發電子和空洞的產生

3 The electron is conducted by the TiO2 nanoparticles to an electrode (anode) and then transferred to a counter electrode (cathode). 藉由 TiO2 奈米顆粒傳導電子到電極 ( 陰極 ) 再傳到對電極 ( 陽極 ) Finally, a liquid electrolyte a mixture of a liquid solvent and ions closes the circuit so that the electron recombines with the hole and is returned to the dye. Electrical energy is generated as the electron moves through the DSC. 最後, 液體電解質 ( 液體溶劑和離子的混合物 ) 封閉電路, 使得電子與電洞重組並返回染料 當電子移動通過 DSC 時產生電能 The novelty of the DSC compared with previous solar cells was the extremely large surface area that was provided for the dye molecules by the TiO2 nanoparticles. 和以前的太陽能電池比較起來,DSC 由 TiO2 奈米顆粒提供給染料的表面積是非常大的 The authors used a 10-micrometre-thick film of these nanoparticles, which had average diameters of about 15nm.Because of the porous structure of the film, its surface area was 780 times larger than its geometric area, analogous to the stacks of thylakoid membranes in chloroplasts in which the electron-transporting reactions of photosynthesis take place. 作者使用厚度 10µm 的薄膜, 其奈米顆粒平均直徑大約為 15nm 因為薄膜的多孔結構, 其表面積比幾何面積大 780 倍, 類似在葉綠體裡的類囊體薄膜進行光合作用的電子轉移 [7] 類囊體是葉綠體中的一種單層膜囊狀結構, 是光合作用中光反應進行的場所 類囊體的存在增大了葉綠體的膜面積, 從而增大了受光面積 After O Regan and Grätzel s results were published, initial improvements in the performance of DSCs were made by the use of mononuclear rather than trinuclear ruthenium-based dye molecules 6, which increased the conversion efficiency from about 7% to more than 11%. O Regan 和 Grätzel s 發布結果之後,DSC 使用 mononuclear( 單核 ) 而不是 trinuclear ruthenium-based( 三核釕 ) 的染料分子來實現初步的性能改善, 它的轉換效率從大約 7% 增加至 11% 以上 ruthenium-based: 以釕元素為中心原子旁邊帶有有機官能機的配位基, 像是 N719 或 Z907

4 [2] [1] A molecularly engineered donor chromophore acceptor dye 3, which has a similar structure to that of chlorophyll, was shown to increase the efficiency further, to 13%. 分子工程上, donor chromophore acceptor ( 供體 - 發色團 - 接受體 ) 染料, 其顯示提高效率至 13% 具有與葉綠素類似的結構 [4] [5] 染料敏化太陽能電池近年來已經獲得廣泛關注, 因為它們的低生產成本, 易於製造和可調諧的光學性質 分子工程卟啉染料使用編碼 SM315 染料, 其特點的 ( 供體 -p 橋 - 接受體 ) 的原型結構, 並提高電解質兼容性, 提高光收穫性能 功率轉換效率為 13%

5 The next step was to replace the liquid electrolyte with a solid hole-transporting material, to create a solid-state DSC 8.This increased the stability of these solar cells and avoided problems associated with liquid leakage. 下一步驟是用具有固態電洞傳輸材料取代液態電解質來製造固態 DSC 8 這是為了提高太陽能電池的穩定性和避免液體洩漏等連帶問題 However, the efficiencies of solid-state DSCs are about half those of their liquid counterparts 9 because the hole-transporting materials do not permeate the TiO2 film as uniformly as liquid electrolytes do. 然而, 固態 DSC 的效率大約為液態的一半 9, 因為電洞傳輸材料不能如液態電解質一樣均勻的滲透 TiO2 薄膜 In the past seven years, the architecture of solid-state DSCs has been adapted for solar cells that, instead of dye, use perovskites compounds that have the general formula ABX3, where A and B are two different positively charged ions and X is a negatively charged ion. 在過去七年裡, 固態 DSC 架構結構已成熟, 七年裡取代了染料, 使用鈣鈦礦, 化合物的一般化學式 ABX3, 其中 A 和 B 是兩個不同的帶正電荷離子,X 是一個帶負電荷離子 Perovskite solar cells (PSCs Fig.1b) have created a tsunami effect among the photovoltaic community because of the excellent light-absorption properties of perovskites. 鈣鈦礦太陽能電池 (PSCs) 在光伏領域產生很巨大的衝擊 ( 海嘯效應 ) 是因為鈣鈦礦優異的光吸收特性 The seminal work of the chemist Tsutomu Miyasaka and colleagues initiated this boom by producing PSCs that used liquid electrolytes 4, and this has been followed by the transition to solid-state PSCs 5. 化學家 Tsutomu Miyasaka 和同事以使用液體電解質的 PSCs 4 引發開創了熱潮, 隨後轉變成固態 PSCs Several groups have demonstrated that the methylammonium lead triiodide (CH3NH3PbI3) perovskite can be used not only as the light-absorbing material, but also as the charge-transporting material 10. 好幾個團隊已經證明甲基銨三碘化鉛 (CH3NH3PbI3) 鈣鈦礦不僅可以作光吸收材 料, 也可作為電荷傳輸材料 10

6 There are several PSC architectures in use today, but the highest reported conversion efficiency (greater than 22%) is based on a structure in which the perovskite is a light absorbing semiconductor, TiO2 acts as the electron acceptor, and a poly(triarylamine) polymer is the hole-transporting material. 目前使用好幾種 PSC 結構, 鈣鈦礦是光吸收半導體, 基於其中 TiO2 作為電子受體, 而三芳基胺聚合物為電洞傳輸材料的結構, 具最高轉換效率 ( 大於 22%) PSCs have the potential to reach efficiencies of more than 25% and have been recognized by the World Economic Forum as one of the top ten emerging technologies of 2016 because of their potential to replace fossil fuels. PSCs 有潛力達到超過 25% 的效率, 並被世界經濟論壇認為是 2016 年十大新興技術之一, 因為它們有潛力取代化石燃料 Nevertheless, PSCs have many drawbacks, such as poor material stability under excessive heat and light exposure, and toxicity because of the presence of lead. 然而,PSCs 具有許多缺點, 例如在過熱和暴露於光下材料穩定性差, 以及由於鉛為毒性物質 Further advances in PSCs, through a combination of innovative steps in materials science, chemistry and device technology, could lead to a revolution in the renewableenergy sector. 透過材料科學, 化學和設備技術的結合創新,PSCs 更進一步的發展, 可再生能源議題將有一場新革命 Solar cells have come a long way since O Regan and Grätzel s landmark paper, and the future looks bright for PSCs as a potential means of obtaining truly renewable energy. 自從 O Regan 和 Grätzel s 的論文立下里程碑以來, 太陽能電池已經走了很長的路, 在未來 PSCs 有潛力變成可再生能源中的主要能源

7 Fig.1a 常規的 DSC 由二氧化鈦 (TiO2) 奈米顆粒組成的膜 ( 作為電子傳導層 ), 釕基染料分子沉積在 TiO2 上 當陽光照射到染料時, 產生帶負電荷的電子 (e - ) 和帶正電荷的電洞 (h + ) 產生電子電洞對 電子通過 TiO2 膜 ( 電子傳導層 ) 擴散到電極 (FTO), 並隨後轉移到對電極 (Pt/FTO)Pt 最後, 電子在與電洞重新結合並被染料再吸收之前, 進入液體電解質 通常鍍 2nm( 可以加速電解液體氧化還原能力 ) Fig. 1b PSC 機制跟 DSC 一樣, 只是把染料改成鈣鈦礦然後液態電解液改成固態電解液 固態電解質又稱為電洞傳導材料 (hole transport material,htm) [6]

8 參考資料 : [1] e=lnms&tbm=isch&sa=x&ved=0ahukewj1xummtinrahxgupqkhyaca8qq_au IBigB&dpr=1#imgrc=n5SaMuJjiKtubM%3A [2] &q=z907&oq=z907&gs_l=img.3..0i19k1l2j0i5i30i19k c.1.64.img j0i30k1.o_1X3D450n8#imgdii=w h_svfflg1vdmm%3a%3bwh_svfflg1vdmm%3a%3bgepdviyezms99m%3a&i mgrc=wh_svfflg1vdmm%3a [3] Mathew, S. et al. Nature Chem. 6, (2014). [4] html [5] [6] [7]