本文關(guān)鍵詞： Cu_2O Cu_2O/SnO_2 CuO 納米薄膜 可見光 光電流　出處：《浙江師范大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：銅氧化物半導(dǎo)體材料具有自然資源豐富、價(jià)格低廉、無毒且禁帶寬度窄等特點(diǎn)。Cu20是一種直接帶隙半導(dǎo)體材料,禁帶寬度約為2.0 eV, CuO的禁帶寬度為1.2 eV。它們對(duì)可見光具有優(yōu)良的吸收,在光催化、太陽能電池和光電化學(xué)電池(PEC)方面擁有廣泛的應(yīng)用前景。納米結(jié)構(gòu)的金屬氧化物具有較大的比表面積,且由于尺寸效應(yīng)使其擁有優(yōu)良的物理和化學(xué)性質(zhì),己被廣泛用于氣體傳感器、鋰離子電池、太陽能電池以及催化等領(lǐng)域。本文在導(dǎo)電玻璃FTO基底上,分別制備了納米島狀Cu20、多孔Cu2O/SnO2和類球狀納米CuO薄膜。利用X射線粉末衍射(XRD)、激光拉曼光譜(Raman)、X射線光電子能譜(XPS)、掃描電子顯微鏡(SEM)和紫外-可見漫反射光譜(UV-Vis)對(duì)樣品的結(jié)構(gòu)、組成、表面形貌和光譜性能進(jìn)行表征,通過光電流響應(yīng)圖譜對(duì)薄膜的光電化學(xué)性能進(jìn)行分析。主要研究?jī)?nèi)容和結(jié)果如以下幾個(gè)方面：1-以0.05 mol-L-1 Cu(NO3)2+1.5 mol·L-1乳酸為基本鍍液,通過兩步恒電流法在FTO基底上沉積花狀Cu膜,然后經(jīng)空氣氣氛下氧化處理獲得納米島狀Cu20薄膜。考察了電沉積-熱氧化的條件對(duì)薄膜形貌、結(jié)構(gòu)、成分及可見光光電性能的影響。SEM、XRD和Raman分析結(jié)果表明,FTO在鍍液中先經(jīng)25 mA-cm-2的電流密度陰極極化10 s,再經(jīng)7.5 mA-cm-2的電流密度陰極極化90 s,最后于175℃恒溫加熱2 h,制備的納米島狀Cu2O薄膜顯示出良好的可見光光電活性和穩(wěn)定性。在0.2 mol-L-1Na2SO4溶液和零偏壓條件下,光電流密度為-0.25 μA·cm-2。2.將電沉積的花狀Cu膜浸漬到預(yù)先制備的SnO2溶膠中,然后低溫煅燒獲得SnO2修飾的多孔Cu2O薄膜(Cu2O/SnO2)。研究了SnO2修飾后對(duì)薄膜結(jié)構(gòu)、組成、形貌、光學(xué)性質(zhì)以及光電性能的影響。XRD、Raman、XPS和SEM結(jié)果表明,SnO2修飾于Cu2O薄膜表面,形成多孔Cu2O/SnO2復(fù)合薄膜。與單相Cu2O相比,Cu2O/SnO2薄膜在可見光區(qū)的吸收強(qiáng)度顯著增強(qiáng),具有更優(yōu)異的光電流響應(yīng)活性和穩(wěn)定性,最佳修飾條件下的光電流密度大小增加了3倍。3.將電沉積的花狀Cu膜經(jīng)空氣氣氛下于300℃恒溫氧化2 h,獲得納米類球狀CuO薄膜。分析了薄膜的結(jié)構(gòu)、形貌、光學(xué)性質(zhì)及光電化學(xué)活性。在0.2 mol·L-1 Na2SO4電解液中,CuO薄膜在零偏壓和可見光照射下表現(xiàn)出優(yōu)良的光電化學(xué)性能,光電流密度為-3.2 μA·cm-2;SnO2修飾后薄膜的光電流密度略微降低,但樣品的穩(wěn)定性得到了提高。
[Abstract]:Cu20 is a direct bandgap semiconductor material with rich natural resources, low price, nontoxic and narrow band gap. The bandgap width of Cu20 is about 2.0 EV. The band gap of CuO is 1. 2 EV. They have excellent absorption of visible light and are photocatalytic. Solar cells and photochemical cells (PECs) have a wide range of applications. Nanostructured metal oxides have a large specific surface area. Because of its excellent physical and chemical properties, it has been widely used in gas sensors, lithium ion batteries, solar cells, catalysis and other fields. This paper is on the conductive glass FTO substrate. Nanocrystalline island Cu20, porous Cu2O/SnO2 and spheroid nanocrystalline CuO thin films were prepared by X-ray powder diffraction (XRD) and laser Raman spectroscopy (LRS). X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV-Vis-UV diffuse reflectance spectroscopy (UV-Vis) were used to characterize the structure, composition, surface morphology and spectral properties of the samples. The photochemical properties of the films were analyzed by photocurrent response atlas. The main research contents and results are as follows: 1-0. 05 mol-L-1 Cunno 3). 21.5 mol 路L -1 lactic acid as the basic bath. The flower-like Cu films were deposited on FTO substrates by two-step constant current method, and then oxidized in air atmosphere to obtain nano-island Cu20 films. The morphology and structure of the films were investigated under the conditions of electrodeposition and thermal oxidation. The effect of composition and visible light on photoelectricity. The results of Raman and XRD show that the current density cathodic polarization is 25 mA-cm-2 for 10 s. The current density cathodic polarization is 90 s at 7.5 mA-cm-2, and then heated at 175 鈩，

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