當兩個不同的氧化物薄膜疊層時，假如吸收層(上層)的導帶與價帶位置都比下層的氧化物薄膜還要低的話，受光激發的跳至導帶的電子會往下層薄膜的導帶去被捕捉，進而產生儲能的效果。最近的研究中有提出Cu2O/TiO2疊層薄膜就有此效果。為了研究此現象，我們使用反應式磁控濺鍍法沉積Ag2O/TiO2之疊層薄膜於玻璃基板上。分別的厚度為200nm及300nm。使用XRD、UV-Vis 分光光譜儀、光致螢光光譜儀及光電化學測試分別測試薄膜的結構、光學性質以及光電化學性質。UV-Vis光譜表現出了薄膜的吸收性質以及能隙。疊層薄膜與單層的Ag2O薄膜比較，在可見光激發後疊層薄膜的吸收特性在可見光區域有上升的情況。從光致螢光光譜中我們可以發現可見光可以有效的激發Ag2O層。光電化學實驗中得到的薄膜光電流，疊層之後的Ag2O/TiO2薄膜比單層的Ag2O及TiO2都有更大的光電流，並且使用光電流來計算光電轉換效率。我們可以從這些結果來確認Ag2O/TiO2疊層薄膜的儲能效果。When two different oxides films stacked together, if the absorption (upper) layer has both its conduction and valence bands levels more negatively lower than that of the layer underneath, then the photo-excited electrons can be forwarded to the underneath layer to become an effect of energy storage. Recent studies discovered that the double layers of Cu2O/TiO2 films possess such capacity. In order to investigate this specific phenomenon, we use a DC magnetron reactive sputtering to deposit a double-layer of Ag2O/TiO2 films on glass substrate. The film thicknesses of the double-layer are 300nm and 200nm respectively. XRD, UV-VIS photospectrometer, photoluminance test and photoelectrochemical test were used to study the structure, optical absorption, band gaps and photocurrents of the stacked films. From XRD, we can confirm the structure of each layer. When compared to the single film of Ag2O, the stacked Ag2O/TiO2 film was found to have enhanced optical absorption under the irradiation of visible light. The PL spectrum revealed that the Ag2O layer can be excited by visible light. The photocurrent of Ag2O/TiO2 film was higher than Ag2O and TiO2 single layer. The IPCE of films was calculated by photocurrents, too. The energy storage of Ag2O/TiO2 film can confirm by these results.
