鈣鈦礦太陽能電池已經成為太陽能電池的新寵兒，歸因於極高的光電轉換效率，吸引全世界的研究團隊爭相研究，從2009年的3.8 %由日本 Miyasaka 團隊首先將CH3NH3PbI3鈣鈦礦材料用於染料敏化太陽能電池結構中，用鈣鈦礦材料取代原先用於光電轉換的小分子染料，並搭配二氧化鈦及液態電解液質，至2014年由韓國研究團隊KRICT將鈣鈦礦太陽能電池光電轉換效率提升到20 %，發展的程度已經超越其他的薄膜太陽能電池，如此高的光電轉換效率因鈣鈦礦獨特的光電特性，包含長的載子擴散長度(Long carrier diffusion length)，有適合的能帶(Appropriate energy gap)，高的吸收係數(High absorption coefficients)，優異的載子遷移率(Excellent carrier mobility )，我們以兩步旋轉塗布法(Two-step spin coating)製作出結構為ITO/PEDOT:PSS/Perovskite/PC61BM/BCP/Al有機型鈣鈦礦太陽能電池，其開路電壓為0.91 V，短路電流密度為16.4 mA/cm2，填充因子為61 %，光電轉換效率為9.1 %，並研究OA-Fe3O4摻雜於PC61BM層對電性之影響，實驗結果為摻雜濃度為30 %時開路電壓為0.93 V，短路電流密度為18.5 mA/cm2，填充因子為63 %，光電轉換效率為10.8 %提升了近19 %。

In 2009, Miyasaka et al. used CH3NH3PbI3 to replace organic dyes in dye-sensitized solar cells (DSSCs) for the first, where the mesoporous titanium oxide (TiO2) and a liquid electrolyte were used. Power conversion efficiency (PCE) of 3.8 % was achieved. Power conversion efficiency (PCE) close to 20 % has been achieved in both mesoporous structure devices as well as photovoltaic heterojunction (PHJ) devices. The highest certified efficiency has reached 20.1 % (non-stabilized) by the KRICT in late 2014. It took less than five years for PCE of perovskite solar cells to increase from 3.8 % to above 20 %, while it takes several decades for other kinds of inorganic solar cells to achieve this and most photovoltaic materials never reach 20 % efficiency. The perovskite solar cells has attracted tremendous research attention due to its unique optical properties such as long carrier diffusion lengths, appropriate energy gap, high absorption coefficients , excellent carrier mobility. We successfully demonstrated that the organic based perovskite solar cell whose structure is ITO/PEDOT:PSS/Perovskite/PC61BM/BCP/Al gave a Voc of 0.91 V, a Jsc of 16.4 mA/cm2, a FF of 61 %, a PCE of 9.1 % via two-step spin coating process. After fabricating the devices in stable process, we started to study on doping OA-Fe3O4 nanoparticles in PC61BM layer. We got the device gave a Voc of 0.93 V, a Jsc of 18.5 mA/cm2, a FF of 63 %, a PCE of 10.8 % by doping 30 wt% OA-Fe3O4 in PC61BM. The power conversion efficiency (PCE) has increased about 19 % after doping 30 wt% OA-Fe3O4 nanoparticles in PC61BM layer.

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