本研究透過電子束蒸鍍法、溶劑熱法和水熱法製備出不同表面形貌的氧化鎢(WO3)光陽極材料，光電化學分析結果顯示：利用水熱法合成之片狀WO3薄膜擁有最佳的表現，在1.23 V (vs. RHE)下，光電流為0.91 mA/cm2，大於電子束蒸鍍法製備之緻密WO3薄膜的0.69 mA/cm2和溶劑熱法合成之刺蝟狀WO3薄膜的0.77 mA/cm2。
光陰極材料部分，靠著乳酸的添加，成功製備出以(111)為優選晶面的氧化亞銅(Cu2O)薄膜，其中，乳酸除了扮演穩定銅離子(Cu2+)的螯合劑角色外，同時避免調配電鍍液pH值時，NaOH添加導致氫氧化銅(Cu(OH)2)的沉澱。光電化學分析結果顯示：電鍍6小時，膜厚3 μm之Cu2O薄膜擁有最佳的表現，在0.00 V (vs. RHE)下，光電流為-0.20 mA/cm2。
最後，將WO3光陽極與Cu2O光陰極應用於本實驗室開發之新型太陽能電池（New Solar Cell, NSC）。NSC之工作原理是利用其可見光光觸媒電極吸收光能後，光觸媒電極表面之光生電子-電洞對可分別與電解質溶液中的電化學活性物質進行氧化與還原反應，藉此將光能轉換成化學能，再透過NSC內建之伽凡尼電池(Galvanic cell)進行放電。在恆電位儀測試下，其最大開環電壓（open circuit voltage, Voc）為0.37 V。此系統之光照面積為0.56 cm2，經過計算得到的最大短路電流密度（short circuit current density, Jsc）為1.33 x 10-3 mA/cm2。
此外，本研究亦透過對電解液預曝氣的實驗，探討電解液組成對NSC系統的影響，結果說明：在氧氣和氫氣同時充足的狀態下，NSC擁有最佳的表現，最大開環電壓可提高到0.45 V，最大短路電流密度約為3.00 x 10-3 mA/cm2。

In this work, photoanodes of tungsten oxide(WO3) catalyst with different surface morphologies have been prepared on fluorine-doped tin oxide (FTO) substrates by electron beam evaporation, solvothermal and hydrothermal method. Photoelectric chemical analysis results carried out at 1.23 V vs. reversible hydrogen electrode (RHE) showed that the sheet-like WO3 film synthesized by hydrothermal method has the best performance. It produces a photocurrent of 0.91 mA/cm2 under simulated sun light (AM1.5G, 100 mW/cm2), higher than the current density 0.69 mA/cm2 of dense WO3 film synthesized by electron beam evaporation and 0.77 mA/cm2 of hedgehog-like WO3 films synthesized by solvothermal method.
In photocathode catalysts part, Cu2O film with (111) preferred orientation was electrodeposited on FTO with the existence of chelating agents(lactic acid). Chelating agents are indispensable in the process of electrodeposition of Cu2O in order to obstruct the precipitation of Cu(OH)2 in alkaline bath and stabilize Cu (II) ions. Photoelectric chemical analysis results showed that Cu2O film of 3 μm thickness has the best performance at 0.00 V (vs. RHE) and it produces a photocurrent of -0.20 mA/cm2.
Finally, the prepared WO3 photoanode and Cu2O photocathode were applied in New Solar Cell (NSC) system, which has been developed by our lab. Free electron-hole pairs are generated when the photoelectrodes are exposed under solar light. The electrons and holes are capable of reacting with the redox-pairs in the electrolyte of two separate chambers, leading the occurrence of reduction and oxidation in the electrolytes to fuel the intrinsic galvanic cell within the NSC for power generation. After investigation by potential static equipment, the NSC cell has an open circuit voltage of 0.37 V with the exposed area of 0.56 cm2. It was found that the short circuit current density was 1.33 x 10-3 mA/cm2.
In addition, the effects of the electrolyte composition for the NSC system were also of concern. It was investigated by applying the pre-purge gas in the electrolyte. The results show that NSC has the best performance when the system is under oxygen-rich and hydrogen-rich state at the same time. In this case, the maximum open circuit voltage was able to increase to 0.45 V and short circuit current density was around 3.00 x 10-3 mA/cm2

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