固態物質鈣鈦礦CH3NH3PbI3 (通式為ABX3)具有高的光吸收能力及寬的吸收範圍、其中的A、B、X組成皆可改變或任意組合，而得到不同的光電特性、加上合成方法簡單等優點，近幾年來，世界各國科學家均投入研究。本論文主要探討perovskite中鹵素的種類、含量及perovskite膜的製程對所組裝的反式鈣鈦礦太陽能電池(結構為ITO/PEDOT:PSS/perovskite/PCBM/Ag )的光電表現之影響。實驗方法是使用一步驟合成法來製備perovskite膜，以簡化元件活性層製備的步驟。研究發現在CH3NH3PbI3中添加Cl，可使其成膜時的聚集程度下降，得到覆蓋度較高的活性層。若在CH3NH3PbI3-xClx添加適量的Br，可獲得較連續且少缺陷的膜，因此相較於用CH3NH3PbI3或CH3NH3PbI3-xCl為活性層的元件，以CH3NH3PbI3-x-yBrxCly為活性層的元件Jsc、Voc及FF皆較高，Voc可達1 V，最高效率為9.58%。再藉由改變旋轉塗佈的條件，可進一步優化元件，使效率增加至10.40%。測試40顆元件的再現性，得到元件的光電轉換效率差異小於1.5%，再現性不錯。另外從CH3NH3PbI3-x-yBrxCly膜之XRD及UV吸收數據，可推導出perovskite膜中的Br可取代I在晶格上位置而Cl因為原子較小，可能摻雜在晶格外的空隙中。;Perovskite (general formula ABX3) such as CH3NH3PbI3 has been proved to be an excellent absorber in solar cell due to its high light absorption ability, broad absorption range, A, B, X can be varied to obtain perovskite with various properties as well as easily synthesized using solution process.In this study, we investigated the photovoltaic properties of inverted perovskite solar cells (device architecture is ITO/PEDOT:PSS/perovskite/PCBM/Ag) based on perovskite containing diverse halide compositions and variousactive film preparation procedures.When the film was prepared withone-step method, addingCl in CH3NH3PbI3precursor solution the resulting film has higher surface coverage.When small amount of Br was added in CH3NH3PbI3-xClx precursor solution, perovskite film with more continuous and less defects was obtained. Therefore the device based on CH3NH3PbI3-x-yBrxCly has better photovoltaic performance compared to those for the cells based onCH3NH3PbI3 or CH3NH3PbI3-xClx active layer.The best performance device has Voc of 1 V and conversion efficiency of 9.58%. Further optimized the device by changing the spin coating conditions the efficiency up to 10.40% was achieved. 40 devices were fabricated at the same condition to test the reproducibility of the fabrication process and found that the difference in the efficiency is less than 1.5% (absolute value). In addition, XRD and absorption data of CH3NH3PbI3-x-yBrxCly films suggests that Br atoms occupied on the lattice of perovskite but Cl may not sit in the lattice point, just randomly distribute in the perovskite grains, due to the smallsize of Cl atom.
