本研究主要目的為製備氧化鋅/二氧化鈦複合型光觸媒提升水溶液中光催化氧化還原反應之效率。在本研究中，將市售二氧化鈦(Degussa P-25)光觸媒分別以濕式含浸法與液相合成法兩種方式製備氧化鋅/二氧化鈦複合型光觸媒，並利用B.E.T.比表面積、SEM、UV-vis DRS、XRD、XPS、螢光光譜儀以及界達電位(Zeta potential)等儀器進行氧化鋅/二氧化鈦複合型光觸媒之物性分析與探討。同時，藉由紫外光/複合型光觸媒程序分別進行光催化氧化酸性紅色四號染料溶液與光催化還原含重鉻酸根溶液，探討氧化鋅/二氧化鈦中複合氧化鋅劑量多寡以及複合型光觸媒鍛燒溫度對其光催化氧化還原效率之影響。
實驗結果顯示：以濕式含浸法相較於液相合成法所製得之複合型光觸媒具有較高的光催化氧化還原效率；製備複合型光觸媒最佳化條件方面指出：複合氧化鋅劑量為2莫爾百分比與觸媒鍛燒溫度為400℃時所製備之氧化鋅/二氧化鈦複合型光觸媒具有最佳的光催化氧化還原效率表現。此外，氧化鋅/二氧化鈦複合型光觸媒與單純二氧化鈦光觸媒做比較發現，氧化鋅/二氧化鈦複合型光觸媒不但具有較高的光催化氧化效率且同時有效大幅提升光催化還原效率，而此光催化機制可藉由過去學者所提出之顆粒間電子傳遞(IPET)程序成功地加以描述。

ZnO/TiO2 coupled photocatalysts were prepared by wetness impregnation (WI) and liquid synthesis (LS) methods in this study. The prepared ZnO/TiO2 coupled photocatalysts were characterized by BET, SEM, UV-vis DRS, XRD, XPS, PL spectra and Zeta potential analyses. The photocatalytic redox efficiency of prepared ZnO/TiO2 was evaluated by photocatalytic oxidation of Acid Red 4 (AR4) and photocatalytic reduction of Cr(VI) in aqueous solutions under UV-365nm illumination. The effects of coupled ZnO dosages and calcined temperatures of ZnO/TiO2 for the photocatalytic redox efficiency were investigated.
The experimental results showed that there were higher photocatalytic redox efficiency with ZnO/TiO2 prepared by WI method than that prepared by LS method not only for the photocatalytic oxidation of AR4 but also for the photocatalytic reduction of Cr(VI) processes. ZnO/TiO2 coupled photocatalysts prepared by WI method in this study substantially promoted the photocatalytic reduction efficiency, but imperceptibly influenced the photocatalytic oxidation efficiency compared with pure TiO2 P-25. The optimal coupled ZnO dosage was 2.0 mol% in ZnO/TiO2 and the optimal calcined temperature of ZnO/TiO2 was 400℃. The photocatalytic mechanisms of photocatalytic redox efficiency of ZnO/TiO2 can be explained by interparticle electron transfer (IPET) process.

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