光電化學解水產氫是非傳統目前主流產氫技術。但因利用太陽能光電解水就能產出高純度的氫氣及氧氣。架構簡單及元件製程容易及擁有良好地化學穩定性，且不會對環境造成汙染。所以以光電化學方法來光電解水產氫是很有發展潛力地。
本論文主要是利用p-型氮化鎵半導體材料來做為光電解水產氫氣的工作電極。此外，我們也在工作電極上製作浸入式指插狀的ITO歐姆電極並有氧化物保護層於反應區ITO電極的設計來增加光載子的攝取效率並讓外加電場更均勻地散佈在反應區中。為了讓工作電極能吸收可見光，並在可見光波段下產氫，p型氮化銦鎵(p-InGaN)材料也被用來製作光電解水產氫的工作電極，並且將p型氮化銦鎵和p型氮化鎵(p-GaN)做比較。實驗結果顯示p型氮化銦鎵的確可吸收可見光波段的光，並產生光電流進而產生氫氣，而其光電流密度也較單純的p型淡化鎵高。
另外，在磊晶時摻入過渡元素錳(Mn)也可讓氮化鎵材料吸收可見光，但由於摻雜錳於氮化鎵中會讓材料的電阻率上升，所以我們在成長p型氮化鎵的同時摻雜錳(p-GaN doped Mn)，希望能提升材料的導電度。但實驗結果指出在成長p型氮化鎵的過程中摻雜錳會讓材料品質下降，加上電阻率過高而無法與ITO形成歐姆接觸之故，導致其光電流比單純的p型氮化鎵低。
由於在成長p型氮化鎵的過程中摻雜錳讓材料品質大幅下降且電阻率還是過高，我們改成將錳摻雜於u型氮化鎵(u-GaN)中(u-GaN doped Mn)，接著再於u-GaN上方成長一層p-GaN來做為光陰極。量測結果證實此結構確實可以吸收可見光，且在-2.2 V的外加偏壓下可以產生氫氣。也注意到電極與ITO 形成ohmic 的重要性。

Photo-Electrochemical Water Splitting, a non-conventional Hydrogen Generation method that has attracted much attention owing to its ways of cleanest in production, low cost, no emissions, using Solar energy and could separate high-purity hydrogen and oxygen from water splitting. And it’s Simple design that is easy to fabricate and good chemical stability.
In this work, we use p-type nitride semiconductor as Photo-electrode that is fabricated to have immersed ITO-Fingers ohmic electrode which has oxide protection layer with ITO-Fingers. This design can improve the efficiencies of Photo-generated carriers’ collection and enhance the activation effect of electric field on the Photo-electrode. Aiming of the Photo-electrode to absorb visible light spectrum and expecting to generate hydrogen gas under visible light, p-type InXGa1-XN alloys is used as Photo-electrode and compared with p-GaN. Result show that InXGa1-XN could absorb the visible light spectrum, photocurrent density is much higher than the p-GaN. Hydrogen generation is observed in both. Besides, we doped Mn element to p-GaN for generate hydrogen gas under visible light. But as the doping of Mn make the materials quality decrease and the photo-electrode become higher electric resistivity, and cannot ohmic contact with ITO. Photocurrent density is much lower than the one without Mn and spectra response cannot obviously see the Mn element absorption in visible light spectrum. So we used the u-GaN doping Mn, which has a p-GaN layer with or without upon the u-GaN layer. The result show the absorption of visible spectrum and could generate hydrogen at -2.2V. And notice the important of the ohmic contact between photo-electrode and the ITO.

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