摘要
在纳米热席卷全球的高科技时代,纳米ZnO因其特有的表面效应、小尺寸效应等特性,广泛应用于橡胶、陶瓷、涂料等行业,并还可用于光催化剂、导电材料、磁性材料等。ZnO的禁带宽度为3.2 eV,对应于波长为387 nm的紫外光。作为一种重要的光催化材料,近年来得到了广泛的研究。但是纯氧化锌的光催化效率低,难以实现工业化应用。半导体材料复合或掺杂能够改善其光催化性能,因此引起了科学界的广泛关注。
本文以乙酸锌(Zn(CH_3COO)_2·2H_2O)、氢氧化锂(LiOH·H_2O)、结晶氯化镉(CdCl_2·2.5H_2O)结晶氯化铝(AlCl_3·6H_2O)为原料,采用溶胶-凝胶法制备了纯纳米ZnO、掺杂镉离子的ZnO和镉铝共掺的ZnO,并用紫外灯作为光源,一定浓度的活性艳蓝X-BR为光催化反应模型污染物,研究了各种ZnO的光催化性能。比较了不同掺杂量镉和镉铝共掺对降解率的影响。采用X射线衍射(XRD)光谱、傅立叶红外(FT-IR)光谱、紫外-可见(UV-Vis)吸收光谱、X光电子能谱(XPS)和高分辨透射电子显微镜(HR-TEM)对其进行了表征。
结果表明,各掺杂粒子均匀的掺入了ZnO晶格中,掺杂镉离子及镉铝共掺使纳米粒子的均匀度增加,且粒径明显变小,提高了ZnO的光催化活性。单掺样品中镉离子掺杂量为0.5%的ZnO的光催化性能最好。共掺样品中0.2%Cd~(2+)-4.5%Al~(3+)的ZnO的光催化性能最好,在30℃下,加入催化剂浓度为0.1 g/L,降解时间为60 min时,对浓度为20 mg/L的活性艳蓝X-BR溶液的降解率达到76.49%。
Nanometer material is known as the 21 most promising materials", particularly nanometer ZnO possesses special properties such as superficial effect and volumetric effect. It is widely used in the industries of pottery, coating, rubber and so on and can also be used as the materials in the photocatalyst, conduction, magnetism etc. The energy gap of bulk material ZnO is 3.2 eV, corresponding to the ultraviolet light of the wavelength 387 nm. As a kind of important photocatalyst, semiconductor material-ZnO has been widely studied in recent years. It is difficult to be applied in engineering due to the lower photocatalytic efficiency of pure ZnO, which however can be improved by compounding semiconductors or doping, therefore it has become the subject of increasing attention in the scientific field.
In this paper, pure ZnO , Cd~(2+)-doped ZnO and Cd~(2+)-Al~(3+) co-doped ZnO were prepared using sol–gel method with zinc acetate dehydrate [Zn(CH_3COO)_2·2H_2O], lithium hydroxide monohydrate (LiOH·H_2O), cadmium chloride (CdCl_2·2.5H_2O), aluminum chloride (AlCl_3·6H_2O) as raw material. The samples were characterized by means of X-ray diffraction (XRD), infrared absorption spectroscopy (IR), UV-Vis spectroscopy and high resolution transmission electron microscope(HR-TEM). The photocatalytic performance of different ZnO samples were studied using ultraviolet lamp as illumination device and reactive brilliant blue X-BR as stimulant pollutant. The relationship between the amount of Al~(3+) doping or Cd~(2+)-Al~(2+)-codoping with degradation rate was also discussed.
The results indicated that the doping was well-proportioned doped into ZnO sample.Moreover Cd~(2+) dopants or Al~(3+)-Cd~(2+) co-doping in ZnO increased the uniformity of the particles and make the particle remarkably smaller so that they are efficient to improve the photocatalytic performance of ZnO. In particular, among the samples of single dopant, 0.5%Cd~(2+)-doped particle ,has the best photocatalytic performance and sa dose 0.2%Cd~(2+)-4.5%Al~(3+) co-doped ZnO particle in the co-doped samples. We also found a quantitative result that when the reaction temperature was 30℃, the degradation rate of reactive brilliant blue X-BR could reach 76.49% by catalyst of 0.1 g/L in 60 min.
引文
[1]冯玉杰,蔡伟民.环境工程中的功能材料[M].北京:化学工业出版社, 2003, 96-97.
[2]田利明. 2001年全国染料有机颜料生产和进出口情况浅析[A]. 2002年全国染料行业信息发布会论文报告集[C],宁波:中国染料工业协会, 2002, 141-153.
[3]张鹏会,孔爱平,韩迪. TiO2光催化降解有机污染物研究进展[J].甘肃石油和化工, 2009(2): 5-9.
[4] Hashimoto K, Irie H, Fujishima A. TiO2 photocatalysis: A historical overview and future prospects[J]. Jpn J Appl Phys, 2005, 44: 8 269-8 285.
[5] Bahnemann D. Photocatalytic water treatment: solar energy applications[J].Solar Energy, 2004, 77: 445.
[6]薛少华,成建家.葸醌染料生产废水处理工艺研究[J].化工环保, 2002, 22(4): 198-203.
[7]张耀斌,全燮,薛大明,杨凤林,赵雅芝.流动态微波催化反应器处理染料废水的工艺稳定性[J].中国环境科学, 2002, 22(3): 235-238.
[8]刘德启,魏敏,张颖,周瑾.稀土催化双氧水氧化耦合处理染料中间体废水研究(I)[J].环境污染与防治, 2002, 24(3):135-137.
[9]林晓华,董新姣.青霉菌X5对活性艳蓝KN-R脱色研究[J].四川环境, 2002, 21(4): 5-12.
[10]郭明远,杨牛珍.纳滤膜分离活性染料溶液的研究[J] .水处理技术, 1996, 22(2): 97-98.
[11] Suzuki N, Miyata T, Sakumoto A. The degradation of anazo dye in aqueous solutions by high-intensity[J]. International Journal of Applied Radiation Isotopes, 1978, 29 (2): 103-108.
[12]顾建忠,朱锦良.蒽醌染料溶液的电子束脱色[J].上海大学学报, 2002, 8(4) : 345-348.
[13]安太成,顾浩飞,陈卫国.超声协同纳米TiO2:光催化降解活性染料的初步研究[J].中山大学学报(自然科学版), 2001,40(5): 131-132.
[14]张颖,王桂茹,李朝晖,等.光催化氧化法处理活性染料水溶液[J].精细化工, 2000, 17(2) : 80-81.
[15] Fujishima A, Honda K. Electrochemical Photocatalysis of Water at Semiconductor Electrode[J]. Nature. 1972, 37: 238-242.
[16] Xu Nanping, Shi Zaifeng, Fan Yiqun. Effects of Particle Size of TiO2 on Photocatalytic Degradation of Methylene Blue in Aqueous Suspensions[J]. Ind Eng ChemRes, 1999, 38:37.
[17]施周,张文辉.环境纳米技术[M] .北京:化学工业出版社, 2003, 135-137.
[18]刘守新,刘鸿.光催化及光电催化基础及应用[M].化学工业出版社, 2006, 52-53.
[19]苏慈生.光催化净化空气涂料[J].现代涂料与徐装. 2000, 1: 8.
[20]王知彩,李小君,王平. SO42-改性TiO2催化降解茜素红水溶液[J].中国环境科学, 2003, 23(5): 535.2
[21]戴文新,王绪绪,付贤智等.卤素离子对TiO2薄膜光致亲水性的影响[J].物理化学学报. 2005, 21(11): 1274-1279.
[22]黄锦勇,刘国光,张万辉等. TiO2光催化还原重金属离子的研究进展[J].环境科学与技术. 2008, 31(12): 104-108.
[23]石振,房宽峻.纳米ZnO的表面改性研究[J].上海涂料,2008,4,45-48.
[24]魏绍东.纳米氧化锌的现状与发展[J].化工设计通讯, 2006, 32(4): 45-52.
[25]关敏,李彦生.国内外纳米ZnO研究和制备概况[J].化工新型材料, 2005, 33(2): 18-21.
[26]李秀梅.纳米氧化锌的性质和用途[J].通化师范学院学报,2004,25(4):54-56.
[27]杨凤霞,刘其丽,毕磊.纳米氧化锌的应用综述[J].安徽化工,2006,32(1):13-17.
[28]郭红丽,卫英慧,候利锋,等.纳米氧化锌压敏陶瓷[J].太原理工大学学报. 2005, 36(2): 115-118.
[29]陈国新,赵石林.纳米UV屏蔽透明涂料的研制[J].现代涂料与涂装, 2003(3):1-3.
[30]近藤刚,本田贵子.紫外线遮蔽[P].特开平8143331, 1996-06-04.
[31]纳米材料在化工生产中的应用. http://www.chemdevelop.com/expert/ew_ page_1 1.asp.
[32]竺玉书.纳米材料在涂料中的应用[J].涂料工业. 2000,(11):24-27.
[33] Koichi Dhtsu, Noriaki Sato. Ultraviolet ray-absorbing composition and process for producing the same[P]. US:5976511, 1999-1l-02.
[34] Nishihama Shji, Fukui Hiroshi. Silica/zinc oxide complex, its production and cosmitic formulated with the same[P]. JP特开平l1-00141l, 1999-01-06.
[35]李群,陈小林,姜万超.纳米氧化锌的制备与纳米功能纺织品的开发(下)[J].染整技术, 2003(25):16-18.
[36] Height M J, Pratsinis S E, Mekasuwandurnrongo, et al. Ag-ZnO catalysts for UV-photodegradation of Methyl-ene blue[J]. Journal Applied Catalysis B: Environrnental, 2006, 63(3-4):305-312.
[37] Shvalagin V V, Slrovu K A L, Kuchmii S Y. Photocatalytic synt hesis of ZnO/Ag nano strusture sensitined by rnethylene blue[J]. Journal Theoretical and Experimenal Chernistry,2005,41(1):13-18.
[38]王国平,石晓波,汪德先.室温固相反应制备纳米氧化锌[J].合肥工业大学学报(自然科学版), 2002, 25(1):32-35.
[39]李萌,司秀娟.纳米氧化锌的制备及应用研究[J].广州化工,2007,1:51-53.
[40]赵新宇,郑柏存,李春中.喷雾热解合成ZnO超细粒子工艺及机理研究[J].无机材料学报, 1996, 11(4): 611-616.
[41]刘建本,易保华,肖卓炳.液相法制备纳米氧化锌的研究(I)[J].吉首大学学报, 2000, 21(2): 9-11.
[42]祖庸,刘超锋,李晓娥.均匀沉淀法合成纳米氧化锌[J].现代化工, 1997, 17(9) : 33-35.
[43]武志刚,高建峰.溶胶-凝胶法制备纳米材料的研究进展[J].精细化工, 2010, 27(1): 21-25.
[44]陈建华,龚竹青.二氧化钛半导体光催化材料离子掺杂[M].北京:科学出版社, 2006,8-9.
[45]吕玮,谢珍珍,林爱琴,等.氧化锌纳米材料的制备及应用研究进展[J].福建师大福清分校学报, 2009,2:1-6.
[46] Gao P, Xie Y, Ying C, et al . Low temperature hydrothermal synthesis of ZnO nanodisk arrays utilizing self-assembly of surfactant molecules at solid-liquid interfaces[J] . J. Nanoparticle Res. , 2006 , 8(1):131-136.
[47] Cheng H B, Cheng J P, Zhang Y J. Large-scale fabrication of ZnO micro-·and nano-structures by microwave thermal evaporation deposition[J]. Journal of Crystal Growth, 2007(299): 34-40.
[48] Kim J H, Hong Y C, Uhm H S. Synthesis of oxide nanop-articles via microwave plasma decomposition of initialmate-rials[J]. Surface&Coatings Technology, 2007(201): 5114-5120.
[49] Peir A M, Domingo C, Peral J, et a1. Nanostructured zinc oxide films grown from microwave activated aqueous solutions[J]. Thin solid Films, 2005(483): 79-83.
[50] Parida K M, Dash S S, Das D P. Physico chemical charac-terization and photocatalytic activity of zinc oxide prepared by various methods[J]. Journal of Coloid and Interface Science, 2006(298): 787-793.
[51] Wang W W, Zhu Y J. Shape-controlled synthesis of zinc oxide by microwave heating using an imidazolium salt[J]. Inorganic Chemistry Communications, 2004(7): 1003-1005.
[52]曹洁,明王军,房宝青,等.离子液体中不同形貌ZnO纳米材料的合成及表征[J].物理化学学报, 2005, 21(6): 668-672.
[53]杨森,倪永红.低维ZnO纳米材料[J].化学进展,2007,19(10): 1510-1516.
[54]邵忠宝,李国荣.高分子网络凝胶法制备纳米ZnO粉料[J].材料研究学报, 2001, 15(6): 681.
[55]刘艳,夏宁,陈日耀,等.静电纺丝法制备ZnO纳米纤维及其光催化性能的研究[J].福建师范大学学报, 2008, 24(1):66-69.
[56]崔启征,童相廷.静电纺丝技术制各无机物纳米纤维的最新研究进展田[J].稀有金属材料与工程, 2006, 35:l167-1170.
[57] Kim S, Jeong M C, Oh B Y, et a1. Fabrication of Zn/ZnO nanoeables through thermal oxidation of Zn nanowires grown by RF magnctron sputtering[J]. Journal of Crystal Growth, 2006, 290(2): 485-489.
[58] Okada T, Kawashima K, Ueda M. Femtosecond laser deposited zinc oxide mm[J]. Applied Phys,A. 2005,81:907-910.
[59] Meng A L, Lin Y S , Wang G X . Preparation of ZnO Nanowires by Electrochemical M ethod[J]. Chinese Journal of Inorganic Chemistry, 2005 ,21:583-587.
[60] Gao Y F , Nagai M, Masuda Y, et al . Electrochemical deposition of ZnO film and its photoluminescence properties[J]. J . Crystal Growth , 2006 , 286: 445 -450.
[61]陆鹏,陆红霞,李世涛,等.多糖绿色合成纳米氧化锌的研究[J].电子元件与料, 2005, 24(10): 33.
[62] Nishio. Photocatalytic decolorization of azo-dye with zinc oxide powder in an external UV light irradiation slurry photoreactor[J]. Journal of Hazardous Materials B, 2006, 138: 106-108.
[63]张海燕,王宝辉,陈颖.光催化氧化处理含油污水的研究[J].化工进展, 2003, 22(1): 67.
[64]李来胜,祝万鹏,张彭义,等. TiO2薄膜光催化臭氧化邻苯二酚[J].催化学报, 2003, 24(3): 163.
[65] Bahemann D, et a1. Synthesis and characterization of magnerite/titanium dioxide composite nan0partic1es[J]. Solar Energy Mater. 1991, 24: 564.
[66]罗平,李亚林,曾召利,等.纳米ZnO光催化降解有机污染物的研究进展[J].三峡环境与生态, 2009, 2(6): 22-27.
[67] Parida K M, Parija S. Photocatalytic degradation of phenol under solar radiation using microwave irradiated zinc oxide [J]. Solar Energy, 2006, 80:1048.
[68]郑怀礼,张峻华,熊文强.纳米TiO2光催化降解有机污染物研究与应用新进展[J].上饶师范学院学报, 2004, 24(8):1003.
[69] Choi W, Termin A, Hffmann MR. The role of metal ion dopants in quantum-sized TiO2:correlation between photoreactivity and charge carrier recombination dynamics[J]. J Phys Chem, 1994, 98(51): 13669-13679.
[70] Wu X S , Ma Z , Qin Y N , et al . Photocatalytic redox activity of doped nanocrystalline TiO2[J]. Wuli Huaxue Xuebao, 2004, 20 (2): 138 - 143.
[71]吴凤清,沅圣平,李晓平.纳米TiO2的制备、表征及光催化性能的研究[J].功能材料, 2001:69-71.
[72]冯良荣,吕绍杰,丘发礼.过渡元素掺杂对纳米TiO2光催化性能的影响[J].化学学报, 2000, 60(3): 463-467.
[73]刘峥,张学会,宋程.水热法制备稀土掺杂纳米TiO2薄膜及光催化降解性能研究[J].稀土. 2010, 31(2): 7-12.
[74] Wang R, Xin J H, Yang Y, et al. The characteristics and photocatalytic activities of silver doped ZnO nanocrystallites[J]. Appl. Surf. Sci. 2004, 227(1-4):312 -317.
[75]徐晓虹,赵娜,吴建锋,田越,王耀. Bi3+掺杂对纳米ZnO形貌及其光催化性能的影响[J].中国陶瓷工业, 2009, 16(1): 21-25.
[76]苏苏,卢士香,徐文国.铝掺杂纳米ZnO颗粒光催化降解活性艳蓝X-BR[J].过程工程学报, 2008, 8(1):54-59.
[77]张灵灵,王艳华,白雪峰. CdS/ZnO复合光催化剂催化分解硫化氢制氢研究[J].化学与黏合, 2008, 30(6): 5-12.
[78]周秉明,申利春.复合纳米SnO2/ZnO光催化降解酿酒废水的研究[J].酿酒科技, 2008, 6: 128-130.
[79] Asahi R, Miyoshi T, Ohwaki T, et al. Visible-light photocatalysis in nitrogen-doped titanium oxides[J]. Science, 2001, 293-269.
[80] Yu Jia Guo, Jimmy C, Cheng Bei, et al. The effect of F-doping and temperature on the structural and tectural evolution of mesoporous TiO2 powders[J]. Solid State Chem. 2003, 173: 372.
[81] Sakata Y, Yamamoto T, Okzaki T, et al. Visible light response of titania photocatalyst containing copper ion[J]. Chem.Lett, 1998, 324(12): 1253-1254.
[82]张锋,李庆霖,杨建军等. TiO2光催化剂的可见光敏化研究[J].催化学报, 1999, 20(3):329-332.
[83] Martyanov I N, Savinov E N, Klabunde K J. Influence of solution composition and ultrasonic treatment on optical spectra of TiO2 aqueous suspensions[J]. Journal of Colloid and InterfaceScience. 2003, 267(1):111-116.
[84] Gordon C, Yang C, Chan S W. Photocatalytic reduction of chromium(VI) in aqueous solution using dye-sensitized nanoscale ZnO under visible light irradiation[J]. Journal of Nanoparticle Research. 2009, (11): 221-230.
[85] Ullah R, Dutta J. Photocatalytic degradation of organic dyes with manganese-doped ZnO nanoparticles[J]. Hazard Mater. 2008,156:194.
[86] Colis S, Bieber H, Colin S B, et al. Magnetic properties of Co-doped ZnO diluted magnetic semiconductors prepared by low-temperature mechanosynthesis[J]. Chem. Phys. Lett. 2006, 422: 529-533.
[87] John H, Hema R, David P. A nonhydrotytic route to organically modified silica[J]. Chem Commun, 1999, (1) : 81 - 82.
[88] Crouzet L, Leclerco D, Mutin P H, et al. Incorporation of siloance and cyclopho sphazene units into metal oxides by a nongy drolytic sol-gel route[J]. Mater Res Soc Symp Proc, 1998, 519: 51 - 56.
[89]关敏,李彦生.国内外纳米ZnO研究和制备概况[J].化工新型材料. 2005, 33(2): 18-21.
[90]李明,李玉芳.纳米氧化锌的生产和应用进展[J].精细化工原料及中间体. 2006, 12: 19-22.
[91]俞娇仙,刘素文等.稀土离子掺杂TiO2纳米晶光催化性能研究[J].山东轻工业学院学报, 2007, 4: 44-46.
[92] Pecchi G, Reye P, Sanhueza P, et al. Photocatalytic degradation of pentachlorophenol on TiO2 sol-gel catalysts[J]. Chemospher, 2001, 43: 141-146.