隨著地球氣候之變遷，開發再生能源之議題已經成為萬眾矚目的焦點，其中的氫能是一種潔淨且來源相當豐富的一種再生能源。於1972年Fujishima與Honda 發表運用半導體材料「二氧化鈦」與鉑金作為電極，並利用照光可產生氫氣與氧氣，開啟了後人將半導體材料運用於光電化學產氫等研究之道路。本實驗藉由水熱合成法製備出氧化鎳薄膜之前驅物且混合二氧化鋯顆粒於其中，並以退火熱處理中輔以不同比例之O2/N2氣氛將其轉換成氧化鎳，將其作為光電極運用於光電化學分解水產氫之研究上，並藉由多種量測輔助可得知材料之特性，並建構出其能帶相關位置。於本研究中使用XRD、SEM、EDX、UV-Vis、UPS、XPS、CV、Mott-Schottky、LSV、EIS等分析儀器量測薄膜之特性，並發現隨著退火O2/N2氣氛之增加，經由XPS量測出之薄膜中Ni3+比例與電化學儀器量測其最大產氫效率、NiO/ITO介面阻抗皆具有關聯性，藉由相關理論可佐證其關聯性皆由極化子所貢獻，並藉由循環伏安法之量測結果得知氧化鎳材料中極化子傳遞電子通道之位置，與線性伏安法之相同電位比較，可發現藉由此極化子通道傳遞電子是在高導電率下進行的，且隨著氧化鎳薄膜中極化子之數目增加，量測出之最大光電產氫效率也會隨之增加。換句話說，本實驗藉由改變退火氧氣氛含量來增加極化子通道之數目以提升光電化學產氫之效率，另外，本研究亦發現混合二氧化鋯顆粒於氧化鎳薄膜中，因為其與氧化鎳價帶接面處易累積電洞之特性，得以幫助產氫效率之提升，並於本實驗中量測出最大產氫效率約為0.34%，估算出之產氫速率約為7.39×10-4 L/s*m^2。

In this research, a nickel oxide and which mixes with sub-micron zirconium dioxide particles thin films were synthesized by hydrothermal method and drop casting method under different annealing atmosphere of oxygen and nitrogen. The characteristics of the material can be measured by a variety of analysis, and the relevant band positions can be constructed. From the results, it was found that increasing of annealing atmosphere of O2/N2 has relation with the ratio of Ni3+/(Ni2++Ni3+) in the film measured by XPS, the maximum hydrogen production efficiency determined by LSV, and the ITO/NiO interface resistance mesured by EIS. The related theory can prove that it is contributed by the polaron. The results show numbers of polaron channel are increased by annealing atmosphere of O2/N2 and more amounts of polaron channel will improve the efficiency of photoelectrochemical water splitting efficiency. In addition, this study also shows that mixing ZrO2 particles in NiO thin films will enhance water splitting efficiency compared to the pure one. This phenomenon is mainly contributed by the interface of valence band of NiO and ZrO2 which will accumulate holes. In this experiment, the maximum photoelectrochemical water splitting efficiency is 0.34%, and the estimated hydrogen production rate is about 7.39×10-4 L/s×m2.

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