近年來鈣鈦礦太陽能電池產業蓬勃發展，在功率轉換效率上有著爆炸性的成長，此現象可歸因於鈣鈦礦材料卓越的特性，例如全色吸收、長電荷擴散長度、高載子遷移率與能隙可調性。其中有機金屬三鹵化物鈣鈦礦被廣泛研究，常採用的電子傳輸層為多孔結構，並使用的金屬氧化物二氧化鈦(TiO2)作為材料，但TiO2具有較大的界面電阻和能階不匹配，以及表面存在許多懸空建導致電荷複合等情況，限制了鈣鈦礦太陽能電池的效率，因此許多研究採用石墨烯摻雜來提升電池表現，但在石墨烯能帶和結構上仍有進一步改善的空間。
因此本篇論文製作多孔二氧化鈦(mesoporous, mp-TiO2)結構的鈣鈦礦太陽能電池，並進一步透過還原氧化石墨烯(reduced graphene oxide, rGO)薄膜與3-氨基丙基三乙氧基矽烷(3-aminopropyltriethoxysilane, APTS)改質之還原氧化石墨烯來調整其功函數調控，除此之外，APTS具有鈍化TiO2之能力，改善了鈣鈦礦晶體孔洞問題以及實現更為匹配的能階上。本論文透過此方法證實可以降低電荷傳輸與界面電荷累積之複合現象，提高電荷之提取率，顯著增加元件短路電流和開路電壓。以旋塗方法製作APTS-rGO之鈣鈦礦太陽能電池展現最佳的表現，開路電壓Voc為 1.04 V、短路電流密度Jsc為 19.9 mA/cm2、填充因子FF為 70.39%與光電轉換效率PCE為 14.6%，與mp- TiO2鈣鈦礦太陽電池相比高出18%的轉換效率。

In recent years, the perovskite solar cell industry has been booming with explosive growth in power conversion efficiency. This phenomenon can be attributed to the excellent properties of perovskite materials, such as panchromatic absorption, long charge diffusion length, high carrier mobility and energy gap tunability. However, TiO2 has a large interfacial resistance and energy level mismatch, as well as the existence of many vacancies on the surface that lead to charge recombination, limiting the efficiency of perovskite solar cells. However, there is still room for further improvement in the graphene energy band and structure.
Therefore, in this paper, we fabricated a mesoporous titanium dioxide (mp-TiO2) structured perovskite solar cell and further adjusted its functional regulation by reducing graphene oxide (rGO) film and 3-aminopropyltriethoxysilane (APTS) modified reduced graphene oxide. In addition, APTS has the ability to passivate TiO2, improve the porosity of perovskite crystals and achieve a better matching of energy levels. It has been demonstrated that the compounding of charge transfer and interfacial charge accumulation can be reduced, the charge extraction rate can be improved, and the short-circuit current and open-circuit voltage of the devices can be significantly increased. The spin-coated APTS-rGO perovskite solar cell shows the best performance with an open-circuit voltage Voc of 1.04 V, short-circuit current density Jsc of 19.9 mA/cm2, fill factor FF of 70.39%, and photovoltaic conversion efficiency PCE of 14.6%, which is 18% higher than that of mp-TiO2 perovskite solar cell.

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