此研究使用的半導體為 n 型氮化鎵，由於氮化鎵在常溫下不易與酸或者是鹼反應，且具有低電阻、能帶橫跨水的氧化還原電位等特性，因此十分合適當作光電解水的工作電極，但礙於其分解電位的位置，使氮化鎵在實驗中容易發生光腐蝕，導致元件的損耗。
在本碩論研究中，利用水熱法沉積羥基氧化鐵或是羥基氧化鐵摻雜鎳化合物來當作催化劑並沉積在氮化鎵上，結果證實了羥基氧化鐵的沉積可提升表面反應動力，並從 SEM 觀察到氮化鎵腐蝕的情況確實被抑制。

Photoelectrochemical solar water splitting is a promising approach to transform light energy into hydrogen energy. Since gallium nitride(GaN) is quite stable at room temperature and its energy band position straddles the redox potential of water, it is very suitable as a working electrode for photoelectrochemical water splitting. However, gallium nitride has photo-corrosion in the experiment, resulting in the decay of lifetime. In this study, we discussed the characteristics and photoelectrochemical (PEC) performance of FeOOH and Ni:FeOOH respectively which deposited by hydrothermal method on n-type gallium nitride substrate. The results showed that the deposition of FeOOH on gallium nitride could increase the interfacial reaction kinetics. We also observed that the corrosion of gallium nitride was improved, and finally enhanced the lifetime.

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