本研究使用三步驟旋轉塗佈法於已成長奈米陣列的導電玻璃上沉積鐵鈦氧薄膜，合成鐵板鈦礦鐵鈦氧-氧化鋅奈米柱與奈米樹枝狀陣列光陽極。使掃用描式電子顯微鏡確認沉積鐵鈦氧的厚度為10 nm，並確認主幹與側枝被鐵鈦氧包覆。利用拉曼光譜儀與穿透式電子顯微鏡確認成功合成鐵板鈦礦鐵鈦氧-氧化鋅奈米柱與奈米樹枝狀陣列光陽極，並兩者間存在磊晶關係。鐵鈦氧-氧化鋅奈米樹枝狀陣列光陽極進行光電化學水分解測量，在1.23 V vs. RHE下光電流為1.04 mA/cm2。同時，經過30分鐘的穩定性測量依然保持80%的光電流。在光電轉換效率測量中，在410-550 nm間保持約7%，確認可利用可見光進利光電化學水分解。進一步以亞硫酸鈉作為電洞犧牲試劑，輔助光電化學水分解測量載子注入效率與載子分離效率。結果顯示，其載子注入效率與載子分離效率則分別為29.2%與60%。載子注入效率與載子分離效率的提升歸因於形成Type II異質結構與表面陷阱態降低。使用O2螢光探針測量法拉第效率為84.3 %。進一步沉積Co-Pi作為共觸媒，在1.23 V vs. RHE下光電流從1.04 mA/cm2上升至1.83 mA/cm2，與起始電壓從0.6 V下降到0.3 V。

In this work, pseudobrookite(Fe2TiO5) layer has been deposited on zinc oxide(ZnO) nanorod(NR) and nanodendrite(ND) array photoanode was successfully prepared by three-step spin-coating. The results show that optimal ZnO/Fe2TiO5 ND array photoanode achieved the photocurrent density of 1.04 mA/cm2 at 1.23 V vs. RHE under illumination AM 1.5G(100 mW/cm2), 31 times and 2.2 times higher that pristine Fe2TiO5 and ZnO/Fe2TiO5 NR array photoanode, respectively. In addition, the photocurrent onset potential shifted by 0.4 V relative to the pristine Fe2TiO5. Furthermore, Na2SO3 was used as the hole scavenger to assist photoelectrochemical to measure the injection efficiency and separation efficiency, the results show that the injection efficiency and separation efficiency of ZnO/Fe2TiO5 ND array photoanode were 29.2% and 60%, respectively. Further to improve the PEC performance by introducing Co-Pi cocatalyst. The ZnO/Fe2TiO5 ND-Co-Pi array photoanode, the photocurrent densities attained at 1.23 V vs. RHE are 1.83 mA/cm2 and the onset potential shifted from 0.6 to 0.3 V.

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