在多晶鈣鈦礦發光二極體領域中，表面與晶界上的缺陷都是影響鈣鈦礦薄膜穩定度的重要原因，本實驗室在2021年發表文章中利用兩性離子氯化膽鹼 (Choline Chloride, ChCl)有效鈍化鈣鈦礦中的帶電缺陷，藉此抑制鈣鈦礦層中的離子遷移，並藉此提升薄膜穩定度。[51]
2022年，韓國首爾大學T. W. Lee團隊透過利用摻雜小分子強酸苄基膦酸(benzylphosphonic acid, BPA)於鈣鈦礦中，不僅成功鈍化鈣鈦礦結構缺陷，更有效減小晶粒尺寸，使元件效能大幅提升。
因此本論文探討摻雜苄基膦酸於本實驗室備置之鈣鈦礦CH3NH3PbBr3前驅液中，並觀察薄膜型態以及光學性質，最後製作成元件進行電性比較，更透過製作不同電洞傳輸層的元件來確認摻雜苄基膦酸於鈣鈦礦薄膜的鈍化效果。
實驗結果也證實苄基膦酸的摻雜能降低鈣鈦礦薄膜的缺陷以降低非輻射複合產生，藉此使摻雜苄基膦酸的鈣鈦礦元件不僅在亮度、電流效率以及壽命下都有明顯提升。

In the field of optoelectronics, perovskite materials not only have high photoelectric conversion efficiency, but also adjustable emission wavelengths, high purity chromaticity, and emission linewidths below 20 nm are important advantages of perovskite materials.
However, in the perovskite film, defects on the surface and grain boundaries are important reasons that affect the stability of the perovskite film, so we passivate the perovskite film by filling the structural defects of perovskite lattice, which can effectively improve the stability of the film.
In 2022, the team of T. W. Lee from Seoul National University successfully passivated the structural defects of perovskite by doping benzylphosphonic acid (BPA) into perovskite. The performance of devices has been greatly improved.
Based on this study, this paper discusses the doping of benzylphosphonic acid in the perovskite precursor. Then observe the film morphology, discuss the optical properties, and compare a device for electrical measurement.
Finally, the devices by doping BPA have higher luminance、current efficiency, and lifetime. Better performance can contribute to BPA successfully passivating the perovskite structure.

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