近年來， p型氧化亞銅半導體受到太陽能電池領域的矚目，因其能隙(2.1eV)可以吸收可見光而適合作為電極板材料，然而其作為電極材料最大的阻礙為在照光下氧化亞銅在水溶液中會不穩定，且電子電洞對再結合速率非常快，因此我們需要利用氫氧化鎳進一步改善氧化亞銅奈米球。本研究主要目的為製備及分析純氧化亞銅之基本性質，與不同比例的Cu2O/Ni(OH)2奈米複合物的晶體結構
、光學性質等的探討，及其分別作為陰極電極板產氫之應用。
本論文實驗結果與討論將分成兩大部分，第一部份為製備Cu2O奈米球，前驅物為五水硫酸銅進行水溶液合成法，透過改變老化時間及酸鹼值控制其顆粒尺寸、結晶性與組成比例，接著將氧化亞銅電極板進行IPCE與PCE量測。第二部分為Cu2O/Ni(OH)2奈米複合物，以六水硝酸鎳為鎳的前驅物，控制前驅物濃度
，合成出不同莫耳比例的Cu2O/Ni(OH)2複合物。Ni(OH)2作為氧化亞銅的保護層，能夠提升Cu2O於電解液穩定性，透過磷光放射光譜證實Ni(OH)2可以接收Cu2O的激發電子，使電子電洞對再結合速率降低，以提高光電化學產氫效率。本實驗使用X 射線繞射儀、場發射掃描式電子顯微鏡與穿透式電子顯微鏡分析其晶體結構、表面形貌，電子能譜儀分析表面化學組成，可見光/紫外光光譜儀量分析光學性質及其光吸收能力，以三電極式光電化學進行量測，評估產氫能力，此研究製備出創新、非貴金屬之複合物材料。

Core shell structure of Cu2O/Ni(OH)2 composites was first synthesized using a two-step solution synthesis method with CuSO4·5H2O and Ni(NO3)2·6H2O as precursors. The composite structure was obtained at room temperature for a time as short as 30 min. The Ni(OH)2 acts as effective co-catalysts suppressing of electron-hole recombination and also the improvement of photoconversion efficiency (PCE) of PECs. The Cu2O/Ni(OH)2 composite NPs with controllable dimensions and compositions were obtained by adjusting the precursor concentration and reaction time. The allows the formation of porous Cu2O/Ni(OH)2 layers with desirable surface areas for effective hydrogen generation. The resulting samples were examined using scanning electron microscope and transmission electron microscopy. The surface chemistry was investigated using X-ray photoelectron spectroscopy. We demonstrate the use of such a novel porous Cu2O/Ni(OH)2 electrode for H2 evolution.

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