本文選題：Bi_2WO_6 + 半導(dǎo)體復(fù)合��； 參考：《寧夏大學(xué)》2017年碩士論文

【摘要】：鎢酸鉍(Bi2WO6)是最簡(jiǎn)單的Aurivillius型氧化物,有特殊的鈣鈦礦層狀結(jié)構(gòu)、較好的穩(wěn)定性和光催化活性受到廣泛的關(guān)注。但Bi2WO6仍存在一些缺點(diǎn):Bi2WO6內(nèi)部的光生電子-空穴對(duì)的復(fù)合幾率較高、對(duì)降解物沒有選擇性、與反應(yīng)體系分離困難等。本論文將針對(duì)Bi2WO6材料的一些缺點(diǎn)進(jìn)行改性研究,具體內(nèi)容如下:(1)以Bi(NO3)3·5H2O和Na2WO4·2H2O分別作為Bi源和W源,水為溶劑,水熱法合成Bi2WO6。采用單一因素法來研究反應(yīng)液的pH對(duì)Bi2WO6活性的影響。通過XRD、SEM、UV-VisDRS等表征手段對(duì)合成材料的組成、形貌、光學(xué)性質(zhì)進(jìn)行表征,并通過降解羅丹明B、泰勒菌素溶液來評(píng)價(jià)對(duì)Bi2WO6的光催化活性。實(shí)驗(yàn)結(jié)果表明:反應(yīng)液的pH為9、反應(yīng)時(shí)間20h、反應(yīng)溫度160℃時(shí)制備Bi2WO6的光催化活性最好,在可見光下光照80min時(shí),Bi2WO6對(duì)羅丹明B、泰勒菌素溶液的降解率都能達(dá)到90%以上。(2)為了解決Bi2WO6光催化活性低的問題,本文將在Bi2WO6上復(fù)合半導(dǎo)體BiOCl,采用水熱-溶劑熱法制備BiOCl/Bi2WO6。以羅丹明B溶液為降解物,研究不同BiOCl的復(fù)合量對(duì)BiOCl/Bi2WO6的光催化活性的影響,實(shí)驗(yàn)結(jié)果表明:15%BiOCl/Bi2WO6的光催化活性最好,在光照20min時(shí)其對(duì)羅丹明B溶液的降解率可達(dá)99%以上,且4次循環(huán)利用后,仍很穩(wěn)定且對(duì)羅丹明B的降解率仍可達(dá)98%。在可見光下,對(duì)印染廢水羅丹明B、抗生素泰勒菌素都具有降解性。與Bi2WO6相比,15%BiOCl/Bi2WO6的光吸收能力增強(qiáng),帶隙降低,PL發(fā)射峰強(qiáng)度降低,且比表面積提高了400%。(3)為了解決光催化劑在降解時(shí)對(duì)降解物沒有選擇性的問題,本文以泰勒菌素為模板劑,BiOCl/Bi2WO6為載體,采用表面聚合法合成了分子印跡型BiOCl/Bi2WO6(MIP-BiOCl/Bi2WO6)。光降解表明:在單一溶液中,MIP-BiOCl/Bi2WO6對(duì)泰勒菌素和羅丹明B溶液的降解率在60min時(shí)分別為90%、17.2%,而BiOCl/Bi2WO6在20min時(shí)對(duì)羅丹明B的降解率和在40min時(shí)對(duì)泰勒菌素的降解率均可達(dá)100%;在泰勒菌素和羅丹明B的混合溶液中,MIP-BiOCl/Bi2WO6在60min時(shí)對(duì)泰勒菌素的降解率在90%以上,對(duì)羅丹明B的降解率僅達(dá)20.1%,BiOCl/Bi2WO6在60min時(shí)對(duì)泰勒菌素的降解率在92%以上,對(duì)羅丹明B的降解率則可達(dá)100%。實(shí)驗(yàn)結(jié)果驗(yàn)證了MIP-BiOCl/Bi2WO6對(duì)模板分子泰勒菌素具有優(yōu)先降解能力。(4)為了解決Bi2WO6的光催化活性低的問題,本文還嘗試使用稀土離子摻雜的方式提高Bi2WO6的光催化活性。在Bi2WO6的基礎(chǔ)上摻雜稀土金屬離子La3+,采用水熱法合成La/Bi2WO6。實(shí)驗(yàn)結(jié)果表明:La3+修飾Bi2WO6后會(huì)導(dǎo)致其晶格參數(shù)d(hkl)值增加而使2θ的值就會(huì)相應(yīng)的減小,La/Bi2WO6的禁帶寬度增加,PL發(fā)射峰強(qiáng)度降低,比表面積提高了550%。5%La/Bi2WO6的光催化活性最好,光照25min時(shí)其對(duì)羅丹明B降解率為98%,在可見光下,對(duì)印染廢水羅丹明B、抗生素泰勒菌素都具有降解性,且循環(huán)利用3次后,其仍很穩(wěn)定且對(duì)羅丹明B的降解率仍可達(dá)97%。(5)為了解決光催化劑在降解污染物后不能及時(shí)分離、回收再利用的問題,本文將La/Bi2WO6與磁性的γ-Fe2O3復(fù)合來制備磁性γ-Fe2O3/La/Bi2WO6復(fù)合光催化劑,利用外加磁場(chǎng)使光催化劑與反應(yīng)體系能夠快速、有效的分離。5%γ-Fe2O3/La/Bi2WO6的光催化活性最好,光降解70min時(shí)其對(duì)羅丹明B的降解率可達(dá)98.6%。在可見光下,對(duì)印染廢水羅丹明B、抗生素泰勒菌素都具有降解性,且循環(huán)利用3次后,其對(duì)羅丹明B的降解率仍可達(dá)95.3%。通過VSM和外磁場(chǎng)的分離實(shí)驗(yàn)可知,5%γ-Fe2O3/La/Bi2WO6的比飽和磁化強(qiáng)度是8.19emu·g-1,通過外加磁場(chǎng)作用使5%γ-Fe2O3/La/Bi2WO6與反應(yīng)溶液快速的分離,達(dá)到分離回收的目的。
[Abstract]:Bismuth tungstate (Bi2WO6) is the simplest Aurivillius type oxide, with a special calcium and titanium layer like structure. The good stability and photocatalytic activity are widely concerned. But there are still some shortcomings in Bi2WO6: the recombination probability of the photoelectron electron hole pair in Bi2WO6 is higher, the degradation is not selective, and the separation of the reaction system is difficult. This paper will study some defects of Bi2WO6 materials. The specific contents are as follows: (1) Bi (NO3) 3. 5H2O and Na2WO4. 2H2O are used as Bi source and W source, water as solvent and hydrothermal method to synthesize Bi2WO6. to study the effect of pH on Bi2WO6 activity. The composition, morphology and optical properties of the material were characterized, and the photocatalytic activity of Bi2WO6 was evaluated by the degradation of Luo Danming B and Taylor bacterin. The results showed that the pH of the reaction liquid was 9, the reaction time was 20h, and the reaction temperature was 160, and the photocatalytic activity of Bi2WO6 was best. When the light illumination was 80min, the Bi2WO6 was to Luo Danming B, Taylor bacteria. The degradation rate of the prime solution can reach more than 90%. (2) in order to solve the problem of low photocatalytic activity of Bi2WO6, this paper will compound semiconductor BiOCl on Bi2WO6, use hydrothermal solvothermal method to prepare BiOCl/Bi2WO6. with Luo Danming B solution as degrading substance, and study the effect of the compound amount of different BiOCl on the photocatalytic activity of BiOCl/Bi2WO6, the experimental result table Ming: 15%BiOCl/Bi2WO6 has the best photocatalytic activity. The degradation rate of Luo Danming B solution can reach more than 99% when light is 20min, and after 4 cycles, it is still stable and the degradation rate of Luo Danming B can still be 98%. in visible light, the Luo Danming B and antibiotic Taylor bacteriocin in printing and dyeing wastewater are all degrading. Compared with Bi2WO6, 15%BiOCl/Bi2WO The light absorption capacity of 6 is enhanced, the band gap is reduced, the intensity of PL emission peak is reduced, and the specific surface area is increased by 400%. (3) in order to solve the problem that the photocatalyst is not selective in degradation. This paper uses Taylor as a template, BiOCl/Bi2WO6 as the carrier, and uses the surface polymerization to synthesize the molecularly imprinted BiOCl/Bi2WO6 (MIP-BiOCl/Bi2WO6). Photodegradation showed that in a single solution, the degradation rate of MIP-BiOCl/Bi2WO6 to Taylor and Luo Danming B was 90%, 17.2% respectively at 60min, while the degradation rate of Luo Danming B and the degradation rate of Taylor to Taylor were 100% at 20min, and MIP-BiOCl/Bi2WO6 in the mixed solution of Taylor and Luo Danming B, MIP-BiOCl/Bi2WO6. At 60min, the degradation rate of Taylor was above 90%, the degradation rate of rhodamine B was only 20.1%, the degradation rate of Taylor was more than 92% at 60min, and the degradation rate of rhodamine B could reach 100%. test results that MIP-BiOCl/Bi2WO6 had the ability to degrade the template molecule Taylor bacteria. (4) to solve Bi2WO 6 of the problem of low photocatalytic activity, this paper also tries to improve the photocatalytic activity of Bi2WO6 by doping rare earth ions. On the basis of Bi2WO6, doping rare earth metal ions La3+ and using hydrothermal method to synthesize La/Bi2WO6. experiment results show that La3+ modified Bi2WO6 will lead to the increase of the lattice parameter d (hkl) value, and the value of 2 theta will be corresponding. Decrease, the width of the band gap of La/Bi2WO6 is increased, the intensity of PL emission peak is reduced, the photocatalytic activity of 550%.5%La/Bi2WO6 is better than the surface area, and the degradation rate of Luo Danming B is 98% when light is 25min. Under visible light, the Luo Danming B and the antibiotic Taylor bacteriin are all degrading, and after 3 cycles, it is still very stable and opposite. The degradation rate of B is still up to 97%. (5). In order to solve the problem that the photocatalyst can not be separated in time and reused after the photocatalytic degradation of pollutants, the La/Bi2WO6 and magnetic gamma -Fe2O3 are combined to prepare the magnetic gamma -Fe2O3/La/Bi2WO6 composite photocatalyst. Using the applied magnetic field, the photocatalyst and the reaction system can quickly and effectively separate.5%. The photocatalytic activity of gamma -Fe2O3/La/Bi2WO6 is the best, and the degradation rate of Luo Danming B can reach 98.6%. when 70min is degraded in visible light. The degradation of Luo Danming B and antibiotic Taylor bacteria in printing and dyeing wastewater, and after 3 cycles of recycling, the degradation rate of Luo Danming B can still be up to 95.3%. through the separation experiment of VSM and external magnetic field, and it can be found that 5% y -Fe2 The specific saturation magnetization of O3/La/Bi2WO6 is 8.19emu g-1. The purpose of separation and recovery is achieved by separating 5% gamma -Fe2O3/La/Bi2WO6 from the reaction solution by the effect of applied magnetic field.

【學(xué)位授予單位】：寧夏大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O643.36;O644.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李超;安佰紅;肖敏;魯英;;花狀鎢酸鉍納米粉體的制備及其光催化性能研究[J];廣東化工;2016年15期

2 梁敏;莫?jiǎng)?chuàng)榮;張金蓮;王馨蔚;;復(fù)合磁性光催化劑Co_(0.5)Zn_(0.5)Fe_2O_4/Bi_2WO_6的制備及其光催化性能[J];化工環(huán)保;2016年02期

3 張琴;汪曉鳳;段芳;陳明清;;Bi_2MoO_6中空微球的制備及其光催化性能[J];無機(jī)化學(xué)學(xué)報(bào);2015年11期

4 劉旺平;王鑫;張帥;樂樹坤;趙謙;姜廷順;;Ag和介孔碳改性Bi_2WO_6光催化劑的合成及其可見光下的光催化性能[J];復(fù)合材料學(xué)報(bào);2015年04期

5 李小娟;湯端蓮;湯帆;何長(zhǎng)發(fā);;Bi_2WO_6-NiFe_2O_4磁性可見光催化劑的制備及其性能研究[J];功能材料;2015年09期

6 王新月;高強(qiáng);高春霞;葛明橋;馮古雨;;α-Fe_2O_3中空磁性納米纖維的制備研究[J];功能材料;2015年08期

7 王艷;馬玉龍;馬琳;常璇;孫瑞珠;王敏;張娟;;泰樂菌素的微生物降解途徑及其降解產(chǎn)物研究[J];環(huán)境科學(xué)學(xué)報(bào);2015年02期

8 郭丹;王蘋;鄭琪穎;王進(jìn);;一步法制備石墨烯復(fù)合花狀鎢酸鉍光催化劑[J];無機(jī)材料學(xué)報(bào);2014年11期

9 吳亞帆;孫紹芳;張坤;李宇亮;關(guān)衛(wèi)省;;鳥巢狀鎢酸鉍的簡(jiǎn)易合成及其光催化性能研究[J];安全與環(huán)境學(xué)報(bào);2014年05期

10 王嘉楠;倪剛;李玲玲;李靜;;BiVO_4/BiOCl復(fù)合材料的制備及其光催化性能的研究[J];現(xiàn)代化工;2014年09期

相關(guān)博士學(xué)位論文 前3條

1 鐘爽;Bi_2WO_6基可見光催化劑的制備及在連續(xù)流反應(yīng)器中降解四環(huán)素廢水的研究[D];吉林大學(xué);2016年

2 李曉敏;磁性鐵氧體基納米復(fù)合材料的制備及吸附和光催化性能研究[D];武漢科技大學(xué);2015年

3 張江;改性Bi_2WO_6的制備、表征及其光催化性能[D];清華大學(xué);2012年

相關(guān)碩士學(xué)位論文 前3條

1 劉雪梅;應(yīng)用于光催化降解有機(jī)污染物的膜研究[D];華東理工大學(xué);2016年

2 李微;復(fù)合BiOI材料的制備及其在印染廢水中的應(yīng)用[D];寧夏大學(xué);2016年

3 李科;納米TiO_2光催化劑的改性及其降解硝基酚的性能研究[D];南昌航空大學(xué);2013年

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