提高有機與鈣鈦礦太陽能電池轉換效率之研究

The Study of Enhancing Power Conversion Efficiency of Organic and Perovskite Solar Cells

林文凱(Wen-Kai Lin)

指導教授 ： 蘇水祥

共同指導教授 ： 橫山明聰(Meiso Yokoyama)

義守大學/電機資訊學院/電子工程學系/博士(2015年)

https://doi.org/10.6343/ISU.2015.00392

摘要

本論文主題為有機與鈣鈦礦太陽能電池之研究，包含以堆疊電洞傳輸層提升可撓式有機太陽能電池元件特性、具三種不同主動層之反式有機太陽能電池以及修飾主動層之鈣鈦礦太陽能電池共三部分。
第一部分探討提高玻璃基板與可撓式基板有機太陽能電池（OSCs）的短路電流和能量轉換效率(PCE)；以玻璃為基板製作具堆疊電洞傳輸層(V2O5/PEDOT:PSS)的有機太陽能電池（ITO/V2O5/PEDOT:PSS/P3HT:PCBM/LiF/Al），其能量轉換效率可達2.67%，為沒有電洞傳輸層有機太陽能電池的十倍，乃由於V2O5/PEDOT:PSS堆疊電洞傳輸層呈現階梯式能帶結構，利於電洞傳輸至陽極並能減少電子電洞再復合。以此V2O5/PEDOT:PSS堆疊電洞傳輸層製作可撓式有機太陽能電池，結構最佳化後元件開路電壓為0.57 V、短路電流密度為6.08 mA/cm2、填充因子為44.64%及能量轉換效率為1.57%，此能量轉換效率為沒有電洞傳輸層之可撓式有機太陽能電池的二十五倍。
第二部分探討三種不同主動層結構之反式有機太陽能電池製備與其特性：a)以P3HT及PCBM混合材料為主動層及利用滴定法製作奈米銀電極和溶液製程製備電洞傳輸層之反式有機太陽能電池，實現以全溶液製程製作反式有機太陽能電池並討論其光電特性；b) 在P3HT:PCBM主動層內摻入奈米碳管，並以摻鈦氧化鋅(TZO)為電動阻擋層，有效降低串聯電阻使短路電流及能量轉換效率提升；c)在P3H:PCBM主動層內摻入酞菁錫(SnPc)及電洞傳輸層中摻入銀奈米粒，酞菁錫為長波長吸收材料可增加主動層光吸收範圍，電洞傳輸層中加入銀奈米粒，可增加光散射與主動層光吸收強度，因此有效提升元件特性，結構最佳化後開路電壓為0.50 V、短路電流密度為10.34 mA/cm2、填充因子為45.33%及能量轉換效率為2.33%。
第三部分探討以鈣鈦礦為主動層之太陽電池特性，製程中以不同種類溶劑修飾主動層及插入緩衝層於元件結構內，甲苯修飾後的鈣鈦礦主動層晶粒完整、元件串聯電阻降低。TPBi作為緩衝層可改善介面接觸和有效阻擋電洞傳輸至陰極。鈣鈦礦太陽能電池結構最佳化後開路電壓為0.90 V、短路電流密度為13.44 mA/cm2、填充因子為64.69%及能量轉換效率為7.81%。

關鍵字

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並列摘要

The main purpose of this dissertation is to enhance the power conversion efficiency (PCE) of organic and perovskite solar cells. It includes the enhancement of performance in flexible organic solar cells (OSCs) by using a stacked hole transporting layer (HTL), the study of three various active layer in the inverted OSCs, and the study of high PCE perovskite solar cells. The dissertation is organized into three parts.
The first part focuses on enhancing the short-circuit current density (Jsc) and PCE of OSCs fabricated on two various substrates, glass and PET. The stacked HTL is vanadium oxide (V2O5)/poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). The OSC configuration comprises glass/ITO/V2O5/PEDOT:PSS /poly(3-hexylthiophene) (P3HT):phenyl C61-butyric acid methylester (PCBM)/LiF/Al. The PCE is 2.67% under simulated AM1.5G illumination of 100 mW/cm2, which is tenfold greater than that of a conventional device without the HTL. The V2O5/PEDOT:PSS stacked HTL provides a smooth film surface for coating P3HT:PCBM active layer, in addition to a stepwise hole-transporting configuration, subsequently increasing charge carrier transporting capability and extracting holes from the active layer. Employing the V2O5/PEDOT:PSS stacked HTL to fabricate OSC onto a flexible PET substrate, the optimized device exhibits an open circuit voltage (Voc) of 0.57 V, Jsc of 6.08 mA/cm2, fill factor (FF) of 44.64%, and PCE of 1.57%. It is twenty-five times greater than that of a conventional flexible OSC without the HTL.
The second part discusses and characterizes three various active layers in the inverted OSCs. a) Fabricating the inverted OSCs use a whole solution process. The hole blocking layer (HBL), active layer and HTL film are all fabricated by spin-coating technique. The anode is formed from Ag nanoparticles (NPs) by drop titration using a Pasteur burette. b) Doping carbon nanotubes into the P3HT:PCBM active layer and using Ti-doped ZnO to be an HBL to reduce series resistances and enhance the PCE of inverted OSCs. c) Wide wavelength inverted OSCs are fabricated and characterized by doping the active layer with long wavelength absorbing tin (II) phthalocyanine (SnPc). The HTL comprises Ag NPs-embedded PEDOT:PSS. The Jsc and PCE are considerably enhanced. Ag NPs result in the enhancement of the scattering and reflection of light, leading to increase absorption efficiency in the active layer of inverted OSCs. Moreover, the SnPc-doped active layer exhibits long wavelength absorption and prevents the active layer from degradation by PCBM clusters. The optimized inverted OSCs exhibit a Voc of 0.50 V, Jsc of 10.34 mA/cm2, FF of 45.33%, and PCE of 2.33% under simulated AM1.5G illumination of 100 mW/cm2, respectively.
In the last part, the perovskite solar cells are fabricated and characterized by both solvent treatment for the active layer and inserting a thin buffer layer. The grain of MAPbI3 active layer agglomerates owing to methylbenzene treatment and the perovskite solar cell shows a decreased series resistance (Rs). The 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi) works as an efficient buffer layer which enhances device performance by forming improved interfacial contact and blocking the hole from transporting to the cathode. The optimized perovskite solar cell exhibits a Voc of 0.90 V, Jsc of 13.44 mA/cm2, FF of 64.69%, and PCE of 7.81% under simulated AM1.5G illumination of 100 mW/cm2, respectively.

並列關鍵字

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