外文翻譯---涂硅對納米二氧化鈦光催化活性和光電化學(xué)性質(zhì)的影響

1、<p>　　中文2500字,1800單詞，9800英文字符</p><p>　　出處：Bui D N, Kang S Z, Li X, et al. Effect of Si doping on the photocatalytic activity and photoelectrochemical property of TiO 2, nanoparticles[J]. Catalysis Commu

2、nications, 2011, 13(1):14-17.</p><p>　　本科生畢業(yè)設(shè)計(jì)外文原文及中文翻譯</p><p>　　學(xué) 院 </p><p>　　專 業(yè)_____ _______</p><p>　　導(dǎo) 師 </p>

3、<p>　　學(xué) 生 </p><p>　　學(xué) 號____ ____</p><p>　　2015年6月11日</p><p>　　Effect of Si doping on the photocatalytic activity and photoelectrochemical proper

4、ty of TiO2 nanoparticles</p><p>　　Duc-Nguyen Bui</p><p><b>　　Abstract</b></p><p>　　Si-doped TiO2 nanoparticles with anatase crystalline phase were prepared by a hydrothe

5、rmal method using acetic acid as the solvent. Photoelectro chemical studies showed that the photocurrent value for the 15% Si-doped TiO2 electrode (54.4μA) was much higher than that of the pure TiO2 electrode (16.7μA).In

6、 addition，the 15% Si-doped TiO2 nanoparticles displayed the highest photocatalytic activity under ultraviolet light irradiation. So doping suitable amount of Si in TiO2 nanoparticles was pro?tab</p><p>　　1.I

7、ntroduction</p><p>　　Commercial dyes have been widely used in industry， such as textile，foodstuff and leather etc，and become an integral part of industrial ef?uents. Most of these dyes are toxic and potentia

8、lly carcinogenic in nature and their removal from industrial ef?uents is a major environmental problem. In fact，various approaches have been developed to eliminate and degrade them， such as biodegradation coagulation，ads

9、orption，membrane process and advanced oxidation process. Photocatalytic degradation using a se</p><p>　　It is known that among various oxide semiconductor photocatalysts，TiO2 is the most widely used one due

10、to its optical and electronic properties，low cost， chemical stability and non-toxicity. However，the photocatalytic ef?ciency of pure TiO2 is very low because of the fast recombination of photogenerated electrons and hole

11、s as well as poor activation of TiO2 by visible light，which makes the progress in the extensive application be impeded. In order to overcome these de?ciencies，several available </p><p>　　Recently，some resear

12、chers employed linear sweep voltammetry (LSV) technique to study the transfer or recombination behavior of photogenerated electrons and holes in the photocatalyst as well as the variation of photocurrent of a photocataly

13、st ?lm electrode under dark and light conditions. In fact， the surface and/or the interface states on the TiO2 nanocrystal ?lm electrode play an important role in the relative electrochemical process that is also include

14、d in the photocatalytic reaction such as</p><p>　　In the present work， we aim to explore the relationship between the photoelectrochemical property and the photocatalytic activity of Si-doped TiO2 nanopartic

15、les. The effect of Si doping in TiO2 nanoparticles will be examined from another angle.</p><p>　　2. Experimental</p><p>　　2.1. Preparation of Si-doped TiO2 nanoparticles and their electrodes<

16、/p><p>　　Si-doped TiO2 nanoparticles were prepared by a hydrothermal method using acetic acid as the solvent [21]. The Si-doped TiO2 nanoparticles are denoted as x% Si? TiO2 (x% ismole per cent of Si). An indiu

17、m–tin oxide (ITO) glass slidewas used as the electrode substrate.The x% Si- TiO2/ITO electrodes with an active area of 1 cm2 Were prepared by the dip-coating method. The detailed procedures were described in the Suppleme

18、ntary data.</p><p>　　2.2. Characterization</p><p>　　The obtained samples were characterized by powder X-ray diffraction (XRD)， transmission electron microscope (TEM)， energy dispersive X-ray ana

19、lysis (EDX)， Fourier transform infrared spectroscopy (FT-IR) and solid diffuse re?ection spectra (DRS). Details are given in the Supplementary data.</p><p>　　2.3. Photoelectrochemical measurements</p>

20、<p>　　Electrochemical experiments were carried out in an electrochemical cell using x% Si-TiO2/ITO as the working electrode， a Pt wire as the counter electrode and a saturated calomel electrode (SCE) as the referen

21、ce electrode. A 0.1 mol L?1 NaOH aqueous solution purged with N2 was used as the electrolyte and a 300WHg lamp served as the UV light source. Linear sweep voltammetry was performed on a PCI4/300 electrochemical analyzer

22、(Gamry， USA) with a scan rate of 5mVs?1. All measurements were carried o</p><p>　　2.4. Photocatalytic experiments</p><p>　　The photocatalytic activity of Si-doped TiO2 nanoparticles was evaluate

23、d by the photocatalytic degradation of methyl orange (MO)aqueous solution (4.6×10?5mol L?1) under UV light irradiation and analyzed by a UV–vis spectrophotometer (Unico UV-2102 PCS，China). The detailed procedures we

24、re described in the Supplementary data.</p><p>　　3. Results and discussion</p><p>　　XRD patterns of pure TiO2 and x% Si?TiO2 are shown in Fig.1.It can be observed that the diffraction patterns o

25、f all x% Si?TiO2 coincide almost with that of pure TiO2. The peaks at 2θ=25.28°,37.79°, 48.05°, 53.89°, 55.09°, 62.68°, 68.76°, 70.30° and 75.02°correspond to the (101), (111)

26、, (200), (105), (211), (204), (116),(220) and (215) planes of anatase phase of TiO2 (JCPDS card no. 21–1272). In addition, no peaks from the SiO2 crystal phase wereobserved for all x% Si-TiO2 samples, which could be</

27、p><p>　　EDX analysis of 15% Si-TiO2 nanoparticles (see Fig. S1) shows that the sample is composed of elements Si, Ti and O. The primary particle sizes of pure TiO2 and 15% Si-TiO2 are about 20 and 13 nm, respec

28、tively, as shown in Fig. 2, which shows that doping Si in TiO2 nanoparticles can decrease the particle size of TiO2.</p><p>　　As displayed in FT-IR spectra of pure TiO2 and 15% Si?TiO2 (Fig.3), two bands obs

29、erved at 3386 cm?1 and 1614 cm?1 are characteristic of O–H bending modes of adsorbed water and hydroxyl groups, respectively. The band at 445 cm?1 is attributed to the Ti–O stretching vibration of crystalline TiO2 phase

30、. Especially, in thespectrum of 15% Si-TiO2 nanoparticles, there exists two new bands at 1079 and 952 cm?1,corresponding to the characteristic stretching vibrations of Si–O–Si and Si–O–Ti, respective</p><p>

31、　　Importantly, solid diffuse re?ection spectra (see Fig. S3) display that there exists a signi?cant blue-shift of the absorption edge for the 15% Si-TiO2 sample, which is ascribed to the incorporating of Si into the TiO2

32、 matrix. It coincides with the result of the literatures reported by Lee et al, and Su et al. The formation of Si–O–Ti bond in the 15% Si?TiO2 can lead to increase of concentration of surface hydroxyl groups (see Fig. 3)

33、. The hydroxyl groups can react with holes to produce hydroxyl</p><p>　　Photocurrent-potential curves of pure TiO2 and x% Si-TiO2 nanoparticles are shown in Fig. 4. The photocurrent values are zero for all t

34、he samples under dark. Under UV irradiation, the photocurrent values for 5%, 10%, 15% and 20% Si-TiO2/ITO electrodes are much higher than that of the pure TiO2/ITO electrode (see Table 1).However, the photocurrent value

35、of the 25% Si-TiO2/ITO electrode (12.9 μA) is lower than that of the pure TiO2/ITO electrode (16.7 μA). These results show that doping Si into th</p><p>　　Fig. 1. XRD patterns of pure TiO2 (a), 5% Si?TiO2 (b

36、), 10% Si?TiO2 (c), 15% Si?TiO2 (d),20% Si?TiO2 (e), and 25% Si?TiO2 (f).</p><p>　　Fig. 2. TEM images of pure TiO2 (a) and 15% Si?TiO2 (b).</p><p>　　Fig. 3. FT-IR spectra of pure TiO2 (a) and 15

37、% Si?TiO2 (b).</p><p>　　Fig. 4. Photocurrent-potential curves of pure TiO2 (A), 5% Si?TiO2 (B), 10% Si?TiO2 (C), 15% Si?TiO2 (D), 20% Si?TiO2 (E), 25% Si-TiO2 (F) under dark (a) and UV light irradiation (b).

38、 Electrolyte: 0.1 mol L?1NaOH solution, scan rate: 5 mV s?1</p><p>　　4. Conclusions</p><p>　　The photoelectrochemical results show that doping of suitable amount Si in TiO2 nanoparticles facilit

39、ates ?owing of photogenerated electrons toward cathode. The effect of Si doping on the photocatalytic activity of TiO2 nanoparticles can be ascribed to the easy transfer and separation of photogenerated electrons and hol

40、es. Namely, there is a strong relationship between the photocurrent and photocatalytic activity of a photocatalyst. The photocurrent as an auxiliary parameter can be correlated wi</p><p>　　涂硅對納米二氧化鈦光催化活性和光電化

41、學(xué)性質(zhì)的影響</p><p>　　Duc-Nguyen Bui</p><p><b>　　摘 要</b></p><p>　　使用乙酸作為溶劑的水熱法來制備涂硅的銳鈦礦型的納米二氧化鈦晶體。光電化學(xué)研究表明：涂15%硅的納米二氧化鈦電極(54.4μA)的光電性質(zhì)高于未涂硅的純納米二氧化鈦電極(16.7μA)。此外，在紫外光的照射下，涂15%

42、硅的納米二氧化鈦擁有最高的光化學(xué)活性。所以在納米二氧化鈦顆粒中摻雜適量的硅有利于光電子的轉(zhuǎn)移以及抑制光電子的重組。因此，納米二氧化鈦的光催化活性得到提高。</p><p><b>　　1.介紹</b></p><p>　　商業(yè)染料被廣泛應(yīng)用于工業(yè)，如紡織、食品、皮革等，成為工業(yè)廢水的組成部分。這些染料中大多數(shù)在本質(zhì)上是有毒的和潛在的致癌危險(xiǎn)的，因此將它們從工業(yè)廢水中去

43、除成為一個主要的環(huán)境問題。事實(shí)上，已有多種方法被用來消除和降低這些危害，例如生物降解凝固、吸附、離子交換膜法以及先進(jìn)的氧化反應(yīng)。使用半導(dǎo)體光催化劑的光催化降解是一個先進(jìn)的氧化過程的一部分，已經(jīng)被證明是一個對有機(jī)污染物降解的綠色技術(shù)。</p><p>　　眾所周知，在各種氧化物形成的半導(dǎo)體催化劑中，由于二氧化鈦光學(xué)和電學(xué)性能、化學(xué)穩(wěn)定性和可降解，成本低，二氧化鈦是應(yīng)用最廣泛的一個半導(dǎo)體催化劑。然而，純二氧化鈦的光催

44、化效率很低，因?yàn)楣怆娮拥牡目焖僦亟M以及可見光照射下的二氧化鈦的光化學(xué)活性很低。這使得二氧化鈦的廣泛應(yīng)用的進(jìn)展受到阻礙。為了克服這些缺陷，有幾個可以采用的技術(shù)，如金屬加載、金屬離子摻雜、陰離子摻雜，混合的兩個大型和小型的半導(dǎo)體帶隙能量和可見光敏感的增敏劑被開發(fā)出來。特別是，硅元素的摻雜二氧化鈦可以大大提高其光催化活性。</p><p>　　最近，一些研究人員使用的線性掃描伏安法（LSV）技術(shù)來研究光電子在光催化劑作

45、用下的轉(zhuǎn)移或重組行為，以及光催化劑電極在黑暗和光照的條件下光電流的變化。實(shí)際上，納米二氧化鈦晶體電極在界面或者表面的相對電化學(xué)過程中起到了至關(guān)重要的作用，其也包括在光催化反應(yīng)中，如轉(zhuǎn)讓，捕獲和交換光電子的重要作用。因此，在通過LSV技術(shù)研究摻硅納米二氧化鈦顆粒的光催化活性的過程中考慮光電流變化是有必要的。</p><p>　　在目前的工作中，我們的目標(biāo)是探索摻硅納米二氧化鈦顆粒光催化活性與光電特性之間的關(guān)系。將從

46、另一個角度研究在納米二氧化鈦顆粒中加入硅的影響。</p><p><b>　　2. 實(shí)驗(yàn)</b></p><p>　　2.1 摻硅納米二氧化鈦顆粒的制備及其電極</p><p>　　使用乙酸作為溶劑的水熱法來制備涂硅的銳鈦礦型的納米二氧化鈦晶體。摻硅的納米二氧化鈦顆粒用硅-二氧化鈦的百分比來表示（百分比是指摩爾質(zhì)量的百分比）。使用ITO作為電極

47、。詳細(xì)的過程參考附錄中的詳細(xì)介紹。</p><p><b>　　2.2 表征</b></p><p>　　對獲得的鈦白粉樣品進(jìn)行X射線衍射分析(XRD)、透射電子顯微鏡(TEM)，能量色散x射線(EDX)分析，傅里葉變換紅外光譜(FT-IR)以及固體漫反射光譜(DRS)等表征。細(xì)節(jié)列于補(bǔ)充數(shù)據(jù)。</p><p>　　2.3 光電化學(xué)測量<

48、/p><p>　　電化學(xué)實(shí)驗(yàn)進(jìn)行了一個電化學(xué)的電池使用摻硅TiO2/ITO作為工作電極，Pt線作為對電極，飽和甘汞電極作為參比電極(SCE)。0.1mol/L氫氧化鈉水溶液作為電解液和300W汞柱燈作為紫外光源。利用線性掃描伏安法進(jìn)行PCI4/300電化學(xué)分析。（美國Gamry的掃描速率5mVs-1所有的測量進(jìn)行時的溫度定為25℃）</p><p><b>　　2.4 光催化實(shí)驗(yàn)&l

49、t;/b></p><p>　　通過對摻硅納米二氧化鈦顆粒在紫外光照射下在甲基橙水溶液(MO)(4.6×10?5mol/L?1)中的光催化活性來研究其光催化性質(zhì)。并使用分光光度計(jì)分析。詳細(xì)的過程描述的補(bǔ)充數(shù)據(jù)。</p><p><b>　　3.結(jié)果與討論</b></p><p>　　XRD表征如圖1所示?？梢杂^察到所有的摻硅二氧

50、化鈦衍射模式幾乎與純TiO2相吻合。此外，從SiO2晶相觀察所有的摻硅TiO2樣品無峰，這可能是由于它的非晶相，或Si作為間隙原子被插入到TiO2的晶格。</p><p>　　摻硅量為15%的納米TiO2的能譜分析表明，樣品是由元素Si，Ti和O的初級粒子大小的純二氧化鈦TiO2和15%的分別為20 nm和13 nm，，如圖2所示，這表明在納米TiO2摻雜硅可以降低TiO2的粒徑。</p><

51、p>　　如圖3所示為純TiO2和摻15%Si? TiO2紅外光譜，在3386cm-1和1614 cm-1具有O–H彎曲吸附的水和羥基基團(tuán)的模式特征觀察兩條帶。在445 cm-1帶是由于鈦伸縮振動TiO2結(jié)晶相。特別是，在摻15%硅納米TiO2的頻譜，存在在1079 cm-1和952 cm-1兩個新的譜帶，對應(yīng)的特征伸縮振動分別是Si–O–Si和Si–O–Ti，。這些結(jié)果表明，Si–O–Ti鍵已在摻15%硅的納米TiO2形成。<

52、;/p><p>　　更重要的是，如圖3所示，存在一個明顯不能為摻15%硅TiO2樣品吸收的邊藍(lán)移，這是歸因于結(jié)合硅到TiO2矩陣。根據(jù)李與蘇等人報(bào)道的文獻(xiàn)結(jié)果。在摻15%Si?TiO2中Si–TiO鍵的形成可以導(dǎo)致表面羥基濃度的增加。羥基發(fā)生反應(yīng)產(chǎn)生的羥基自由基與孔。羥基自由基是一種強(qiáng)氧化劑。所以會提高TiO2光催化活性。</p><p>　　Fig. 1. XRD光譜圖 純TiO2 (a),

53、 5% Si?TiO2 (b), 10% Si?TiO2 (c), 15% Si?TiO2 (d),20% Si?TiO2 (e), and 25% Si?TiO2 (f).</p><p>　　摻硅的納米TiO2的光電流電位曲線如圖4所示。光電流值是黑暗條件下的所有樣本。在紫外光照射下，光電流值為5%，10%，15%和20%的TiO2/ ITO電極遠(yuǎn)高于純TiO2／ITO電極。然而，25%的TiO2／ITO電極

54、電流值（12.9μA）低于純TiO2／ITO電極（16.7μA）。這些結(jié)果表明，在納米TiO2摻雜Si具有積極的作用和對摻硅TiO2/ ITO電極的光電流產(chǎn)生負(fù)面影響。一個可能的解釋是，Si原子空隙是被迫進(jìn)入TiO2晶格的制備過程中建立一個Si–O–Ti鍵。為轉(zhuǎn)移的橋梁，光生電子可以很容易地移動通過Si–O–Ti鍵的表面。這個過程可以促進(jìn)光生電子的傳輸和量子產(chǎn)量導(dǎo)致的電流值的提高。此外，Si摻雜降低了TiO2的粒徑（圖2）和增加的結(jié)果表

55、明，降解摻硅15% TiO2納米粒子顯示光催化活性最高，X%的Si? TiO2光催化活性的X %S? TiO2/ ITO電極的光電流的變化一致。此外，光催化降解的動力學(xué)曲線在15%?Mo Si納米TiO2。結(jié)果表明，自我規(guī)范好的表面的TiO2納米粒子，這意味著更多的電子/空穴可以逃脫TiO2納米粒子的表面。因此，TiO2／ITO電極的電流</p><p>　　Fig. 2. TEM 圖像 （純TiO2 (a) 1

56、5% Si?TiO2 (b)）</p><p>　　Fig. 3. FT-IR 光譜（純TiO2 (a) and 15% Si?TiO2 (b)）</p><p>　　Fig. 4.光電流電位曲線（純TiO2 (a), 5% Si?TiO2 (b), 10% Si?TiO2 (c), 15% Si?TiO2 (d), 20% Si?TiO2 (e), 25% Si-TiO2 (f) und

57、er dark (a) and UV light irradiation (b). Electrolyte: 0.1 mol L?1NaOH solution, scan rate: 5 mV s?1 ）</p><p><b>　　4. 結(jié)論</b></p><p>　　光電化學(xué)的結(jié)果表明，在TiO2納米顆粒中摻雜適量Si有利于光生電子向陰極移動。Si摻雜對納米Ti