水溶性染料在PbTiO3体系中的光催化降解

以ＰｂＴｉＯ３为光催化剂，对多种水溶性染料的光催化降解反应进行了研究，结果表明：光降解脱色效率与染料溶液匠ＰＨ值、光照时间、光源种类及催化剂用量等因素有关，染料浓度为１０ｍｇ／ＬＰＨ＝６，催化剂用量为１００ｍｇ／５０ｍｌ，直接以太阳光作光源，光照１ｈ以后，脱色率达９０５以上，有机染料中硫和氮元素转化为ＳＯ４＾２－和ＮＯ３的生成率分别为８５％和６５％。     

K7[Mn(H2O)CrW11O39]/PANI/SnO2三元复合材料的合成、表征及光催化性能研究

本文采用静电自组装法成功制备了三元复合材料K₈[Mn(H₂O)CrW₁₁O₃₉]/PANI/SnO₂,并使用UV-vis、XRD、XPS、FT-IR、SEM-EDS和N₂吸附-脱附等手段对其进行表征。并且通过光催化降解刚果红染料的实验,确定了反应的最佳条件为:刚果红溶液的初始浓度为10 mg·L^-1,初始pH值为2,催化剂用量为0.002 g时,溶液脱色率可达98.1%。重复回收三次后,溶液脱色率仍达到88.1%。     

铁酸钴复合氧化物制备及光催化研究

采用一种新型燃烧剂抗坏血酸,燃烧法快速制备铁酸钴的复合氧化物.经XRD考察硝酸铁和硝酸钴摩尔比对复合氧化物的影响,电镜表征复合氧化物的形貌、BET表征复合氧化物的比表面积以及紫外表征复合氧化物的紫外吸收性能.以甲基橙为目标降解物对铁酸钴的复合氧化物进行光催化研究.考察了溶液酸度、光照时间、催化剂用量和双氧水用量等条件对光催化效果的影响.最佳光催化条件:当Fe(NO3)3,Co(NO3)3和抗坏血酸的物质的量比为1∶2∶1时所制备的铁酸钴复合氧化物,催化剂用量为200mg/L,溶液的酸度为pH=6;脱色的最佳条件为当Fe(NO3)3,Co(NO3)3和抗坏血酸的物质的量比为1∶3∶1时所制备的复合氧化物,催化剂用量为100mg/L时,pH=4;复合氧化物还对六价铬的吸附率为58%,对铅的吸附率为45%.     

H2O2/TiO2超声协同光降解活性艳橙的研究

以活性艳橙溶液为模拟废水,通过H₂O₂/TiO₂超声(US)协同作用光降解活性艳橙溶液,探讨了TiO₂催化剂用量、H₂O₂用量、活性艳橙溶液的初始浓度、pH值、TiO₂催化剂锻烧温度等对活性艳橙溶液降解率的影响,并比较了几种不同作用方式对活性艳橙溶液的降解效果.结果表明:UV/H₂O₂/TiO₂/US协同作用降解活性艳橙溶液的效果最好;当活性艳橙溶液的初始浓度为20 mg·L^-1,pH＝5,TiO₂用量为0.4 g·L^-1,H₂O₂用量为0.4 ml·L^-1时,降解率可达92.06%.     

K8[Co(H2O)W11MnO39]/PANI/ZrO2复合材料 的制备及其光催化性能的研究

本文通过静电自主装法对K_8[Co(H_2O)W_(11)MnO_(39)]/PANI/ZrO_2复合材料进行制备。采用红外、紫外、XRD、SEM、EDS和氮气吸附表征手段对合成的K_8[Co(H_2O)W_(11)MnO_(39)]/PANI/ZrO_2复合材料进行表征,并且研究了K_8[Co(H_2O)W_(11)MnO_(39)]/PANI/ZrO_2复合材料对龙胆紫染料的光催化性能,探讨了催化剂用量、pH、染料初始浓度和不同催化剂对光降解效率的影响,并且考察了重复回收效果。结果表明:龙胆紫溶液初始浓度为2mg·L~(-1),pH=2,催化剂用量为0.15g,紫外光照200min时脱色率可达94.8%,且重复利用第三次后脱色率仍达80.7%。     

NiFe2O4对刚果红的光催化降解性能研究

采用水热法合成了尖晶石型NiFe₂O₄,并利用X射线粉末衍射仪对其物相进行了表征,利用紫外-可见分光光度计对其光催化降解刚果红的性能进行了研究。以刚果红为光催化降解底物,探究了刚果红初始浓度、催化剂用量、溶液pH、不同光源等因素对NiFe₂O₄光催化降解刚果红活性的影响。结果表明,当刚果红溶液浓度为20 mg/L、催化剂NiFe₂O₄的用量为0.065 g、pH 2~10、在太阳光下照射480 min时,刚果红的降解率高达99%以上,催化剂性能稳定,适合处理刚果红类有机污染物。     

磷钨酸对甲基橙光催化降解的初步研究

在自制的光化学反应器中,以紫外灯为光源,以磷钨酸为光催化剂,研究了其对模拟甲基橙染料废水的光催化脱色降解的影响。实验结果表明,催化剂加入量、溶液初始浓度、不同光强度是影响催化降解效果的重要因素。最佳催化条件为20 mg/L的甲基橙溶液在紫外灯(16W)辐射下,光催化剂磷钨酸用量为1.5 g/L。     

新型杂多酸盐光催化降解亚甲基蓝染料废水

以水热自组装法合成的新型杂多酸盐[PMo₈V₆O₄₂][Co(Phen)₂][Him]₂·2H₃O·3H₂O(1),通过红外光谱、拉曼光谱、紫外-可见光谱、光电子能谱和X粉末衍射等技术手段进行表征。 以此物质为催化剂光催化降解亚甲基蓝染料废水。 分别讨论催化剂投加量、亚甲基蓝废水初始浓度、废水溶液酸度(pH)对亚甲基蓝降解率的影响。 实验结果表明:催化剂投加量为50 mg/L、亚甲基蓝初始浓度为4 mg/L、模拟废水溶液的初始pH=1、降解时间220 min时,废水降解率可达到99.2%。 光催化动力学分析显示,以合成杂多酸盐为催化剂光催化降解亚甲基蓝废水降解过程满足一级动力学方程,该一级方程反应速率常数为0.0144 min^-1,拟合常数为0.9918。 另外,此催化剂还表现出较好的重复使用性能,连续使用5 次后降解率仍为92.4%。     

半导体复合CdS/TiO2催化剂改性及冷冻-光催化组合方法应用的初步研究

采用溶胶-凝胶法制备多孔氧化钛,并耦合CdS,制备多孔耦合CdS/TiO₂催化剂.煅烧温度为700℃,CdS掺杂比例为3%时,催化剂性能较优.以太阳光为光源,考查了溴氨酸初始浓度对其降解效果的影响,并采用冷冻-光催化组合方法对较高浓度的溴氨酸废水的处理进行了初步研究.浓度为500 mg/L的溴氨酸模拟废水(其中氯化钠质量浓度为500 mg/L)经冷冻后,当成冰率为70%时,体系中冰层的Na⁺含量、总有机碳(TOC)和吸光度分别由209.88 mg/L,208.90 mg/L和8.120降至19.06 mg/L,24.80 mg/L和0.638.使用多孔耦合催化剂对该冰层融水光降解,光照6 h,褪色率和TOC去除率分别达到100%和87.04%.     

复合纳米微粒Rh3+/TiO2/SnO2的合成、表征及光催化降解4-(2-吡啶偶氮)间苯二酚的研究

采用溶胶 凝胶法制备复合纳米微粒Rh³⁺/TiO₂/SnO₂作系列光催化剂,运用BET、XRD等技术对样品进行了表征.讨论了影响污染物4 (2 吡啶偶氮)间苯二酚(PAR)光催化降解率的主要因素,实验结果表明:以Rh³⁺/TiO₂/SnO₂为复合光催化剂,当m(TiO₂)∶m(SnO₂)=56:44,ω(Rh³⁺)=2.0%,催化剂用量为1.0 g,通入空气的流量为10.0 L/min,试液的质量分数为2.0×10^-6,pH=7.0时,光照2h,PAR的降解率达到96.2%.     

光催化降解染料ZnO催化剂的性能

光催化法是20世纪70年代发展起来的新型水处理技术，即以某些半导体材料为催化剂，利用光催化法来降解环境污染物。该方法工艺简单，成本较低，在常温下能使大多数不能或难于生物降解的有毒有机物彻底氧化分解。近年来研究最多的是TiO2，由于其带隙较宽(3．2eV)，只能吸收波长λ≤387nm的紫外光，因此研制新型光催化剂仍是重要课题。     

Investigation of photocatalytic effect of SnO2 nanoparticles synthesized by hydrothermal method on the decolorization of two organic dyes

Tin oxide nanoparticles about 4 nm in size were successfully synthesized using hydrothermal method. The photocatalytic activity of the particles was determined by the decolorization of malachite green (MG) and titanium yellow (TY) under UV light. 12 ppm of MG and TY were used for the solution with an initial volume of 100 mL. The amounts of catalysts were 10, 30 and 50 mg. The effect of the catalyst loading on the reaction kinetic parameters and the decolorization rate constants (k) were determined. In order to reveal the photocatalytic efficiency of the nano particles, further experiments were conducted with bulk SnO(2). The oxygen species registered no observable effect on the reaction mechanism as nitrogen bubbling leads to no change in decolorization rates. Results showed that the synthesized nano tin oxide particles represent excellent photocatalytic activity for the decolorization of 12 ppm MG under UV light with 150 min of irradiation time. The energies of the highest occupied molecular orbital (HOMO) E(HOMO) of the dyes were also calculated by using the quantum chemical software in order to discuss the differences for the decolorization of two dyes. Electrical energy efficiency values for the decolorization of two dyes were also calculated.     

Keggin和Dawson结构多金属氧酸盐光催化脱色偶氮染料

The investigation photocatalytic degradation of three azo dyes solution(Acid Mordant Navy Blue RRN,Acid Mordant Black PV,Acid Mordant Brown RH) under UV light irradiation using the polyoxometalates as catalyst was reported in this article.The research results showed that the photocatalytic activity of Keggin catalyst is higher than that of Dawson,and the catalyst α-H4SiW12O40 had the best efficiency to the photocatalytic decoloration of RRN.In 350 mg·L-1(30 mL) RRN solution,the optimum reaction condition wa...     

Guanidinium Iodides-based Ionic Liquids： Synthesis and Application for Dye-sensitized Solar Cells（DSSCs）

A series of guanidinium ionic liquids(GILs) was designed, synthesized, and used as electrolytes for dye-sensitized solar celIs(DSSCs). The effect of electrolytes containing GILs on the photovoltaic performance of DSSCs was investigated. It is demonstrated that these GILs are promising for being used as electrolytes for DSSCs and a conversion efficiency of 4.1% can be obtained under AM 1.5 sun light irradiation.     

Solvent-free ionic liquid electrolytes without elemental iodine for dye-sensitized solar cells

A new type of electrolyte with a sulfide/polysulfide redox couple and I(-) was prepared as a solvent-free ionic liquid for application in dye-sensitized solar cells, reaching efficiencies of 5.2-6.4% under AM 1.5G, 100 mW cm(-2) light illumination, and 6.6% efficiency was obtained under 0.1 sun irradiation.     

钙钛矿型复合氧化物LaFeO3和LaCoO3的光催化活性

采用柠檬酸法合成了钙钛矿复合氧化物ＬａＦｅＯ３和ＬａＣｏＯ３,并以其为光催化剂对水溶性染料进行光催化降解实验,研究了不同光源和不同光照时间对降解脱色率的影响。结果表明ＬａＦｅＯ３和ＬａＣｏＯ３均有较强的光催化活性,而ＬａＣｏＯ３的光催化活性明显高于ＬａＦｅＯ３,这主要与Ｆｅ＾３＋和Ｃｏ＾３＋离子的电子构型以及Ｆｅ－Ｏ间和Ｃｏ－Ｏ间的结合能有关。     

Contribution of singlet oxygen to the accelerated decolorizing of dye mixtures

Binary mixtures of dispersed dyes, which during irradiation with polychromatic light give an effect of accelerated decolorization, were studied. Quantum yields of the formation of singlet oxygen by individual dyes were estimated during irradiation of solutions in ethyl acetate with light of 435 and 546 nm as well as quantum yields of the reaction of dyes with singlet oxygen. It was found that the contribution of the reaction of dyes with singlet oxygen to the effects of accelerated decolorization were vanishingly small. The quantum yield of the photodestruction of dyes in a mixture was 10^–3-10^–5 and the quantum yield of reaction with singlet oxygen was less than 10^–6. It was concluded that accelerated decolorization of the systems studied is not determined by reaction with singlet oxygen.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2014–2017, September, 1991.     

Optimization of the oxalate catalyzed photoelectro-Fenton process under visible light for removal of Reactive Red 195 using a carbon paper cathode

The decolorization of Reactive Red 195 (RR195) by the oxalate catalyzed photoelectro-Fenton (PEF) process using carbon paper electrode as a cathode under visible light was studied. Comparison between electro-Fenton (EF), PEF, and PEF/oxalate processes for the removal of RR195 showed that color removal follows in decreasing order: PEF/oxalate > PEF > EF. Response surface methodology (RSM) was used to determine the effects of the four main independent parameters (initial dye, oxalate and Fe³⁺ concentrations, and reaction time) on decolorization efficiency. A high coefficient of determination value (R ² = 0.963) has resulted from the analysis of variance (ANOVA). The optimum values of the initial Fe³⁺ concentration, the initial amount of oxalate, the initial dye concentration, and the reaction time were found to be 0.3 mM, 0.6 mM, 20 mg/L, and 120 min, respectively. A high decolorization efficiency (>93 %) was experimentally obtained for RR195 under the established optimum conditions. The response surface plots were employed to establish the effect of experimental parameters on the decolorization efficiency. These results clearly indicated the success of RSM as a suitable method for optimizing the operating conditions. The mineralization of the dye was investigated by total organic carbon (TOC) measurement. 96.2 % mineralization of 50 mg/L RR195 was observed at 9 h.     

Structures and photoactive properties of poly(styrene‐co‐vinylbenzophenone)

Poly(styrene‐co‐vinylbenzophenone) prepared by a graft reaction on polystyrene revealed photoactive properties under irradiation of UVA. The photoactive structural features of the polymer were examined via electron paramagnetic resonance (EPR) under irradiation of UVA and fluorescent light. The photoactive functions of the polymer such as antimicrobial performance and dye decolorization ability were investigated. The results revealed that the poly(styrene‐co‐vinylbenzophenone) could generate radicals under fluorescent and UVA irradiation, and some radicals could stay alive for about 30 min in a dark chamber. The photoexcited polymer showed excellent antibacterial ability and decolorization effect on methylene blue and methyl orange dye under both daylight and UVA light. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2423–2430, 2008     

Fe2O3/TiO2纳米管的制备及其光电催化降解染料废水性能

采用阴极电沉积和阳极氧化法制备了Fe2O3改性TiO2纳米管(Fe2O3/TiO2-NTs)电极,运用场发射扫描电子显微镜、透射电子显微镜、X射线衍射和紫外-可见漫反射光谱等手段对其进行了表征,考察了其光电化学性能,并研究了复合电极光电催化降解甲基橙染料废水的反应性能.结果表明,Fe2O3的负载成功地将TiO2-NTs的光响应区间拓宽到可见光区域,Fe2O3/TiO2-NTs复合电极的光电流密度达到TiO2-NTs电极的3倍.在光电催化反应中,Fe2O3/TiO2-NTs复合电极对甲基橙的脱色效果明显优于TiO2-NTs电极,以Fe2O3/TiO2-NTs为阳极,光照5min,甲基橙溶液的脱色率可达90%以上.