太陽能可以光電催化水分解的方式產氫，而奈米材料像是奈米線、奈米顆粒等，因為有較大表面積及豐富的反應位置被視為很好的光電催化材料。氧化亞銅是一種具發展性的光電催化材料，但其光激發載子的高再結合率和自身氧化還原的光腐蝕效應是實際水分解應用中必須解決的難題。本研究中，以濺鍍銅膜通過電化學陽極處理的方式生成氫氧化銅奈米線陣列，並在高溫下退火使其轉化成氧化亞銅奈米線陣列。為生成氧化亞銅/氧化銅的核殼結構，本實驗以端點偵測法控制銅在FTO導電玻璃上的剩餘量。氧化亞銅/氧化銅的能帶排列結構有利於將氧化亞銅中產生的光激發電子導向氧化銅/溶液界面以進行水分解。在1M Na2SO4溶液中以AM 1.5G的模擬太陽光照射，Cu2O/CuO核殼奈米線陣列有5.3 mA/cm2的高光電流值。然而，在光電催化的測試過程中，隨著照光時間的增長，光電流值逐漸下降。因此本研究也針對影響Cu2O/CuO核殼奈米線陣列光電流及穩定性的原因做進一步探討。

Solar energy can be used to produce hydrogen fuel by splitting water through photoelectrochemical reaction. Nanomaterials including nanoparticles and nanowires that possess large surface area and abundant reactive sites are inherently good photocatalytic materials. Although cuprous oxide (Cu2O) is known as a promising photocathode material in a photoelectrochemical cell, its high electron-hole recombination rate and self-oxidation/reduction have been the major concerns for practical water-splitting applications. In this study, a Cu2O nanowire array was prepared by growing Cu(OH)2 nanowires on sputtered Cu film through electrochemical anodization, followed by thermal treatment at elevated temperature. An end-point detection method was used to monitor the amount of residual Cu on the fluorine doped tin oxide (FTO) substrate in order to control the morphology of Cu2O/CuO core-shell structure. The band alignment of the Cu2O/CuO core-shell structure helps covey photoelectrons generated in Cu2O to the CuO/solution interface for water splitting. The Cu2O/CuO core-shell nanowire array demonstrates a high photocurrent of 5.3 mA/cm2 in a 1M Na2SO4 solution under AM 1.5G illumination. However, the photocurrent gradually decreased with light exposure time during the photoelectrochemical testing. The factors affecting the photocurrent and stability of the Cu2O/CuO core-shell nanowire array are discussed in this study.

目錄
摘要 I
Abstract II
致謝 III
目錄 IV
圖目錄 VI
表目錄 VIII
第1章 緒論 1
1.1 前言 1
1.2 研究動機 2
第2章 文獻回顧 3
2.1 光電催化產氫 3
2.1.1 產氫技術 3
2.1.2 光催化水分解(photocatalytic water splitting) 4
2.1.3 光電催化水分解(Photoelectrochemical water splitting) 5
2.2 Cu2O作為光電催化材料 7
2.2.1 Cu2O做為光電催化材料之瓶頸 7
2.2.2 能帶排列對光電催化性質之助益 9
2.3 Cu2O奈米線於光電催化應用 10
2.3.1 奈米線光學性質 10
2.3.2 奈米線光觸媒特性 11
第3章 實驗步驟 12
3.1 實驗設計與流程 12
3.1.1 實驗藥品 12
3.1.2 Cu2O奈米線製備 12
3.2 陽極處理Cu(OH)2及其退火後Cu2O奈米線分析 15
3.2.1 X光結晶繞射分析(XRD)分析 15
3.2.2 掃描式電子顯微鏡(SEM) 分析 15
3.2.3 穿透式電子顯微鏡(TEM) 分析 16
3.2.4 X光光電子能譜儀(XPS)分析 16
3.2.5 光電催化性質分析 16
3.2.6 電化學阻抗測量 17
3.2.7 Mott-Schottky半導體性質分析 18
3.2.8 電化學表面積測量-雙電層電容法 19
3.3 實驗設備與儀器 20
第4章 結果討論 21
4.1 端點偵測(End-point Detection)處理對Cu(OH)2轉換之Cu2O奈米線影響 21
4.1.1 Cu(OH)2奈米線的成核機制 21
4.1.2 Cu(OH)2退火後之Cu2O奈米線微結構分析 22
4.1.3 Cu(OH)2退火後Cu2O奈米線X射線繞射光譜分析(XRD) 24
4.1.4 端點偵測法生成之奈米線穿透式電子顯微鏡(TEM)分析 25
4.1.5 Cu2O/CuO核殼奈米線光電催化性質分析 26
4.1.6 相異殘餘銅量與Cu2O/CuO核殼結構對光電催化性質影響 27
4.1.7 端點偵測法之Cu2O/CuO核殼奈米線光腐蝕路徑 29
4.2 陽極處理電流密度對Cu(OH)2及其退火Cu2O/CuO核殼奈米線之影響 30
4.2.1 Cu(OH)2及其退火後Cu2O/CuO核殼奈米線微結構分析 30
4.2.2 Cu(OH)2及其退火後Cu2O奈米線X射線繞射光譜分析(XRD) 34
4.2.3 相異電流密度生成之Cu2O/CuO核殼奈米線反應位置分析 35
4.2.4 Cu2O/CuO核殼奈米線光電催化性質分析 37
4.3 電洞傳導層Cu2Te對奈米線性質影響 39
4.3.1 濺鍍Cu2Te成分與性質分析 40
4.3.2 不同厚度Cu2Te層之Cu2O/CuO核殼奈米線陣列結構電化學阻抗測量結果 42
4.3.3 不同厚度Cu2Te對Cu2O/CuO核殼奈米線的光電催化性質影響 44
4.4 施加偏壓對光電催化穩定性的影響 46
第5章 結論 48
第6章 參考文獻 49

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