本研究從理論與實驗面向，解析Bi12O17Cl2的晶體結構，並探索Bi12O17Cl2光催化應用可行性。第一部分透過理論的方法，從BiOCl、Bi24O31Cl10與Bi3O4Cl系列鉍氯氧化物之結構差異，結合JCPDS資料庫中的晶格常數與理論X光繞射圖譜的資訊，歸納O/Cl計量變化對於晶體結構的影響，並利用此趨勢推論Bi12O17Cl2的結構模型。最終結果顯示，Bi12O17Cl2同樣是有著Bi2O2層狀結構，且由五層[Bi2O2](六層Bi平面)所構成，而Cl則分布於兩組Bi-O結構之間的結構。
本研究的第二部分則是使用常溫化學沉澱法合成Bi12O17Cl2，透過調整沉澱劑的氫氧化鈉（NaOH）濃度。當NaOH濃度為1.4 M至7.0 M之間，可於常溫下獲得Bi12O17Cl2結晶相。從實驗結果來看，Bi12O17Cl2為片狀晶體，且主要顯露晶面為{0 0 1}面，而以NaOH濃度為4.0 M合成出的BN40，相對來說其晶體減少了往[0 0 1]方向的成長，使得晶體厚度變薄，讓光電子也較容易擴散至晶體表面，利於進行光催化反應，同時也提高了整體比表面積，增加反應的機會，因此具有最高的光催化降解羅丹明B染料的效率。

This study analyzed the crystal structure of Bi12O17Cl2 from both theoretical and experimental perspectives, as well as explored the photocatalytic applications. In the first part, the structural differences among bismuth oxychlorides including BiOCl, Bi24O31Cl10, and Bi3O4Cl were investigated using theoretical methods. By combining the lattice parameters and theoretical X-ray diffraction patterns from the JCPDS database, the impact of O/Cl stoichiometry on the crystal structure was deduced. Based on the trend, a structural model for Bi12O17Cl2 was proposed. The result indicates that the structure of Bi12O17Cl2 contains [Bi2O2] layered structure, consisting of five layers of [Bi2O2] with six Bi planes, while Cl is distributed within the structure between two parts of Bi-O structures.
The second part of this study involved the synthesis of Bi12O17Cl2 using the chemical precipitation method by adjusting the concentration of NaOH. Bi12O17Cl2 phase could be obtained at room temperature when the NaOH concentration ranged from 1.4 M to 7.0 M. Based on the experimental results, Bi12O17Cl2 exhibited a plate-like crystal with {0 0 1} plane being the mainly exposed surface. In comparison, BN40 synthesized with 4.0 M NaOH reduced growth along the [0 0 1] direction, resulting in thinner crystal thickness. This increased the diffusion of photogenerated electrons to the crystal surface, promoting photocatalytic reactions. Additionally, its higher surface area also provided more reaction opportunities. As the result, BN40 exhibited the highest efficiency in photocatalytic degradation of Rhodamine B dye.

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