本研究論文成功地直接在FTO基板上利用簡便的水熱法輔以旋轉塗佈法製備出p-Cu2O/n-ZnO 異質接面膜。本研究主要透過XRD、SEM、TEM和XPS進行材料的相鑑定、表面形貌觀察以及組成元素的束縛能分布分析。

此p-Cu2O/n-ZnO 異質接面膜可被應用於亞甲藍(MB)水溶液的光降解。經過三小時的光照射，大約80%的亞甲藍水溶液會被降解且其降解反應常數(k)約為8.9 × 10-3 min-1。此外，藉由UV-Vis及UPS的結果所繪製出的能帶圖，我們推測直接型Z-scheme的異質接合是造成p-Cu2O/n-ZnO 異質接面膜的光降解效率得以被提升之可能的機制。而從Al/n-ZnO/p-Cu2O/FTO異質接面二極體的電流密度-電壓(J-V)之特性來看，其在黑暗中具有優異的整流效果。然而，在-3V的逆向偏壓下照射紫外光，其電流密度和在黑暗中相比可被提升將近80倍，這也意味著這個二極體具備優異的紫外光感測性質。

A p-Cu2O/n-ZnO heterojunction film was directly fabricated on fluorine-doped tin oxide (FTO) substrate through a facile hydrothermal method with the assistance of a spin-coating method in this study. The crystal phases, surface morphology, and binding states of constituent elements and their distribution were characterized by X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS).

A p-Cu2O/n-ZnO heterojunction film was applied to the photodegradation of methylene blue (MB). After 3-h illumination, approximately 80 % of MB was degraded and the degradation rate constant (k) was approximately 8.9 × 10-3 min-1. Moreover, a direct Z-scheme heterojunction was proposed as a potential mechanism for the improvement of photodegradation efficiency based on the energy band diagram, which was constructed from the UV-Vis and UPS results. The current density-voltage (J-V) characteristics of an Al/n-ZnO/p-Cu2O/FTO heterojunction diode showed an excellent rectifying behavior in the dark while the current density under illumination increased approximately 80 times at a reverse bias of -3 V compared with that in the dark, implying an excellent UV sensing property of the sample.

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