| 摘要註: |
太陽能電池近年來發展趨勢為低汙染性、低製造成本、元件製作簡易、高光電轉換效率,也因此有研究團隊開發出新型態鈣鈦礦結構(Perovskite)太陽能電池,這種結構電池符合上述特性,已引起大量學者投入此研究,使得此種結構的太陽能電池轉換效率預測可高達20%。近來因為新型態吸光物質的開發與進展,使得此類型的太陽能電池引起各界的關注。本研究是以鈣鈦礦結構材料 - CH3NH3PbX3作為光吸收材料,以往在染敏太陽能電池中,常以有機染料作為光敏材料,但有鑑於有機染料的高價格以及合成上較為不易,因此實驗取代傳統之有機染料之光敏劑,作為太陽能電池應用且發展成為新一代鈣鈦礦太陽能電池。論文研究分為三部份,於研究第一部份中介紹如何製備鈣鈦礦結構材料:CH3NH3PbI3、CH3NH3PbI2Br與CH3NH3PbI2Cl等三種鈣鈦礦材料,經由X射線繞射分析儀(XRD)、X光能譜分析儀(EDS)與場發射電子顯微鏡(SEM)鑑定此三種光電材料合成成功;接著以紫外-可見光光譜(UV-Vis)、螢光光譜(PL)及循環伏安圖譜(CV),觀察材料之光電性質及能隙。第二部分使用上述合成的光電材料導入染料敏化太陽能電池元件,以市售之TiO2及P3HT做為電子與電洞傳輸層,ITOglass /TiO2/Perovskite/P3HT/Al結構組成元件。首先利用CH3NH3PbI3合成材料塗佈為光敏化層,探討不同退火溫度及不同旋塗厚度對太陽能電池元件效率之影響。發現最佳退火溫度為100℃/30min光敏化材料旋塗層數4層(1500rpm)時,量測短路電流5.10mA/cm2,FF值45.36%時具有最佳光電轉換效率1.54 %。第三部分使用上述合成的最佳參數條件進行CH3NH3PbI2Br、CH3NH3PbI2Cl之光吸收層塗佈,並比較此三種鈣鈦礦其太陽能電池元件效率之影響。合成之三種鈣鈦礦相光敏化材料CH3NH3PbI3、CH3NH3PbI2Br與CH3NH3PbI2Cl分別具有1.55eV、1.82eV和1.92eV的能隙,因CH3NH3PbI2Cl在400~550nm具有較強吸收波峰,且Pb與取代的鹵化物陰電性差異為CH3NH3PbI2Cl >CH3NH3PbI2Br >CH3NH3PbI3,故量測出鈣鈦礦取代鹵化物之光電轉換效率具有CH3NH3PbI2Cl >CH3NH3PbI2Br >CH3NH3PbI3的狀況。以CH3NH3PbI2Cl作為光吸收材料組裝的太陽能電池,量測短路電流5.23 mA/cm2,FF值45.95%時具有最佳的光電轉換效率1.99%。 In recent years, the development of solar cells is toward low pollution and manufacturing cost, simple component and high power conversion efficiency. Therefore the research teamdeveloped a new type of perovskite structure cell in accordance with the above mentioned characteristics. A lot of scholars participate in the relevant research leading to the prediction of solar cell conversion efficiency up to 20%. Lately, owing to the development and advance of the new type of light absorbing material, this type of solar cell has brought about considerable interests of the general public. This study is based on the perovskite material - CH3NH3PbX3 as a light absorbing material. In a traditional dye-sensitized solar cell, the organic dye is often used as a photosensitizer. In view of the organic dyes are high prices and difficult to be synthesized, the present experiments synthesized inorganic light absorber to substitute the traditional organic dye photosensitizers. This research was divided into three parts. In the first part of the study, weintroduced how to prepare three perovskite materials, including CH3NH3PbI3, CH3NH3PbI2Br and CH3NH3PbI2Cl. The synthesized materials were then characterized with X-ray diffraction analyzer (XRD), field-emission scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (XRD). After characterization, the successful syntheses of three materials were confirmed. UV-vis spectroscopy, fluorescence spectroscopy (PL) spectra and cyclic voltammetry (CV), were alsocarried out to investigatetheiroptoelectronic properties and energy gaps. The secondpart was to introduce the three synthesized materials to fabricate the Dye-sensitized Solar Cells. By using TiO2 as the electron transporting layer and P3HT as the hole transporting layer, the solar cells had the structures of ITO glass/TiO2/Perovskite/P3HT/Al.Atfirst, using CH3NH3PbI3as thephotosensitive layer, the effect of annealing temperature and thickness of the active layer on the photovoltaic performance was investigated. It was found that at the annealing temp. of 100℃/30min and the thickness of perovskite was 4 layers, the solar cell device had the optimal efficiency of 1.54%with a Jsc of 5.10mA/cm2and FF of 45.36%. The third partwas to use the above-mentionedoptimal operatingparameters to proceed the coating of CH3NH3PbI2Br and CH3NH3PbI2Cllight absorbingmaterials. The device performances of the three kinds of solar cells were compared. It was found that thethreekinds of photosensitivematerials (CH3NH3PbI3, CH3NH3PbI2Br and CH3NH3PbI2Cl) have the energy gap of 1.55eV, 1.82eV and 1.92eV, respectively. Because CH3NH3PbI2Cl has a strongabsorptionpeak at 400~500 nm, and the differences of electronegativity between Pb and the substituted elements were in the order of CH3NH3PbI2Cl >CH3NH3PbI2Br> CH3NH3PbI3, the photovoltaic performances were in the order of CH3NH3PbI2Cl >CH3NH3PbI2Br> CH3NH3PbI3. It was found that the device using the CH3NH3PbI2Cl as the photosensitive material had the highest power conversion efficiency of 1.99% with a Jsc of 5.23mA/cm2 and FF of 45.95%. |