微乳液溶剂热法微/纳米草酸钐的合成与表征

采用微乳液溶剂热法,在CTAB/正辛烷/正丁醇/硝酸钐水溶液（草酸钾水溶液）所形成的反相微乳液体系中,合成不同尺寸的棒状微/纳米Sm2（C2O4）3.利用X射线衍射（XRD）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）对Sm2（C2O4）3的形貌和尺寸进行了表征.结果表明,微/纳米Sm2（C2O4）3的尺寸随着水与CTAB的摩尔比（ω）、反应时间的增大而增大.     

纳米TiO_2负载棉织物的光催化性能

以钛酸丁酯(TBT)为前驱体,在超声低温条件下,在棉织物表面原位生成纳米级锐钛矿型TiO2,并对其光催化性能进行了研究。通过均匀试验设计,以在紫外光和可见光辐射下亚甲基蓝脱色率为评价目标值,对钛酸丁酯、冰乙酸及超声时间三个因素进行回归分析,得出优化工艺:钛酸丁酯4 m L,超声2.5 h,紫外光下脱色率为85.94%;钛酸丁酯4 m L,超声5.5 h,可见光下脱色率为76.58%。并对比了超声及常规水热法处理后负载TiO2织物的光催化性能。X射线衍射(XRD)分析可知,溶液中残留的TiO2粉体主要为锐钛矿型,粒径5.3 nm;扫描电镜(SEM)观察发现,棉织物表面不均匀分布大量纳米级TiO2颗粒;紫外-可见光谱(UV-VIS)测试显示,负载TiO2的织物在紫外光区有明显吸收,可见光区吸收平台上移,超声及水热处理时间的延长有利于增强织物对紫外和可见光的吸收。     

果糖基碳微球的制备及其吸附性能研究

以果糖为碳前驱体、聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物（Pluronic P123）为模板剂,采用软模板水热碳化法制备果糖碳微球。利用扫描电子显微镜（SEM）、透射电子显微镜（TEM）对其形貌进行表征,探究果糖碳微球最佳制备条件,并对其吸附亚甲基蓝的性能及影响因素进行了研究。结果表明,水热碳化时间为6 h时,果糖碳微球尺寸分布均匀,表面光滑。在最佳吸附条件下,果糖碳微球对亚甲基蓝的吸附量可达91.43 mg/g,经5次吸附循环后其吸附量仍为初始吸附量的76.9%,具有良好的循环使用性能;其吸附过程符合准二级吸附动力学,Langmuir等温吸附模型对其吸附过程的拟合更准确,表明亚甲基蓝以单分子层方式吸附于果糖碳微球表面,亚甲基蓝各分子间无相互作用。     

光接枝丙烯酸棉纤维素基TiO2/C光催化剂的制备与光催化性

针对回收利用废弃棉织物的功能和附加值低的问题,采用光接枝丙烯酸的废弃棉纤维素为模板,钛酸四丁酯为前驱体,无水乙醇为溶剂,经磷酸二氢铵处理后,通过表面溶胶凝胶法和火焰燃烧的方法制备具有纤维形貌的锐钛矿型二氧化钛和炭（TiO2/C） 的复合光催化材料。分别研究了丙烯酸接枝改性、磷酸二氢铵处理对TiO2/C光催化性能的影响。采用扫描电子显微镜、X射线衍射和热重分析对TiO2/C光催化材料的表面形貌和晶体结构以及质量损失率进行分析。结果表明,质量分数为30%的丙烯酸光接枝改性棉织物,经质量分数为15%的磷酸二氢铵溶液浸渍处理,用钛酸丁酯溶液抽滤沉积10次,在空气中燃烧2h制得的TiO2/C光催化剂具有较为优异的光催化性能。此时的光催化剂中锐钛矿型二氧的粒度相对较小,分布较均匀,更有利于光催化降解。     

TEMPO氧化魔芋葡甘露聚糖微球的制备及其在运载食品活性因子中的应用

以2,2,6,6-四甲基哌啶-1-氧自由基（2,2,6,6-tetramethyl-piperidine-1-oxyl,TEMPO）为催化剂,次氯酸钠为氧化剂,对魔芋甘露聚糖（konjac glucomannan,KGM）进行氧化,制备出氧化度为80%的TEMPO氧化魔芋多糖（TEMPOoxidizedkonjac glucomannan,OKGM）。用OKGM为原料、Fe3＋为交联剂借助双重乳液法制备微球。内油相中包覆β-胡萝卜素,多糖水相吸附花色苷,实现亲疏水活性因子的共装载。红外光谱显示出KGM上羟基成功氧化为羧基;MTT法验证了OKGM没有细胞毒性;采用单因素试验,确定制备微球的最佳工艺条件是OKGM质量分数10%、FeSO4·7H2O与OKGM质量比1∶5、交联时间30 min、交联温度35 ℃;通过动态光散射法发现微球粒径分布在20～40 μm之间,平均粒径为26.8 μm;通过扫描电子显微镜和原子力显微镜观察了微球的表面形貌;荧光共聚焦显微镜显示微球中能够同时分布着花色苷和β-胡萝卜素。结果表明OKGM微球在多种活性因子的共装载方面有良好的应用前景。     

碳纤维负载TiO2光催化薄膜的制备及其性能

 以PAN基碳纤维(CF)为基体,钛酸丁酯为前驱体,通过溶胶-凝胶浸渍涂覆法将TiO2负载于经过表面修饰的CF上,制备CF负载的TiO2光催化薄膜。采用扫描电子显微镜（SEM）和X射线衍射仪（XRD）表征了制备材料的形态结构,通过超声震荡清洗测试了CF对TiO2的负载牢度,以质量浓度为80 mg/L的酸性橙Ⅱ溶液为目标降解物,测试了材料在紫外线光照下的催化性能。结果表明：溶胶浓度影响制备材料的形态结构、CF对TiO2的负载率及负载牢度;溶胶浓度和退火温度对制备材料的催化活性有明显的影响。Ti浓度为0.5 mol/L的溶胶制备的TiO2/CF负载牢度好,负载率高,催化活性好。     

微米级二氧化硅微球的制备及其粒径调控

为解决传统St?ber法制备的SiO2微球粒径不易调控且尺寸难以突破微米级的问题,首先采用溶剂调控法合成了均匀亚微米级SiO2悬浊液（种子溶液）,然后通过种子生长法制备大粒径的微米级SiO2微球。测试与分析结果表明,SiO2微球粒径为300～1 600 nm,尺寸均匀可控;匀速加料有助于提高微球的均匀性。该方法具有低成本、可重复操作的优势。     

热处理温度对溶胶-凝胶法制备的TiO2薄膜性能的影响

采用溶胶-凝胶法在普通载波片上制备了TiO2薄膜,用AFM、XRD、UV-VIS分光光度计、润湿角测量仪研究了薄膜的表面形貌和热处理温度对薄膜各种性能的影响.结果表明:TiO2薄膜由大量的球形纳米颗粒构成,颗粒大小均匀;随着热处理温度的升高,TiO2薄膜晶粒尺寸不断长大,亲水性和光催化性能提高;600℃时部分TiO2由锐钛矿转变为金红石相,使紫外光吸收线“红移”.     

用吸附相反应技术制备弱光响应的铈掺杂TiO2复合光催化剂

为拓展多相光催化的实际应用和满足环境治理的严格要求,利用吸附相反应技术设计并制备了弱紫外光响应高效的TiO2 多组分催化剂。借助透射电子显微镜、高分辨率透射电子显微镜和X 射线衍射分析了不同焙烧温度下铈离子掺杂量对催化剂形貌的影响,并结合光致发光光谱和弱光降解甲基橙过程,探索了催化剂结构变化对光生载流子复合率和弱光催化活性的影响。结果表明,当掺杂量较低（小于0.10%）时,铈离子掺入引起TiO2 晶格膨胀,从而引入光生载流子的浅能级捕获中心,提升了催化活性;在较高掺杂量（0.20% 以上）时, 铈离子掺入抑制了TiO2 结晶,催化剂中大量无定形TiO2 严重抑制了其活性;焙烧温度越高,铈离子掺杂量对催化剂结构和活性的影响越显著;降解高浓度甲基橙时,催化性能最好的催化剂的活性是商用P 25 的2 倍多。     

射频磁控溅射制备纳米TiO_2薄膜及其表征

采用射频磁控溅射法制备纳米TiO2薄膜。采用X射线衍射仪（XRD）、原子扫描电镜（AFM）对纳米TiO2薄膜晶体结构、表面形貌进行表征。研究了热处理对纳米TiO2薄膜晶体结构、表面形貌的影响。结果表明,热处理后TiO2颗粒变小,薄膜更加致密。热处理前TiO2薄膜没有出现晶相,呈无定型,500℃条件下热处理1h后出现锐钛矿相,升高热处理温度未出现金红石相。     

Mass production and photocatalytic activity of highly crystalline metastable single-phase Bi₂₀TiO₃₂ nanosheets

Highly crystalline metastable bismuth titanate (Bi??TiO??) nanosheets are prepared via a simple green wet chemical route for the first time. The Bi??TiO??)photocatalysts were characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy dispersive spectrum analysis (EDS), X-ray diffraction (XRD), N? adsorption-desorption (BET), and UV-vis diffuse reflectance spectroscopy (DRS). Inspiringly, Bi??TiO?? nanosheets showed high photocatalytic activity for the degradation of nonbiodegradable azo dye under simulated sunlight and visible-light irradiation. The experimental results showed that the photocatalytic activity of the Bi??TiO?? nanosheets was superior to the commercial Degussa P25 TiO?, and demonstrated that the morphology and crystal structure have a distinct effect on the photocatalytic activity. The reasons for the high photocatalytic activity and the formation mechanism of Bi??TiO?? nanosheets are also discussed.     

二氧化钛纳米管的制备及其光催化性能

为提高TiO_2的光催化性能,通过电化学阳极氧化法在金属钛箔基体上制备了结构有序的TiO_2纳米管(TiO_2NTs),并以此为基础通过连续离子层吸附反应技术(SILAR)制备了Ag、CdS共修饰的TiO_2纳米管(AgCdS/TiO_2NTs)。采用X射线衍射仪、扫描电子显微镜、透射电子显微镜、元素分析仪和紫外可见漫反射光谱等表征手段,对Ag-CdS/TiO_2NTs形貌结构、元素组成和光吸收特性等进行了表征,并研究了Ag、CdS修饰后的TiO_2纳米管的光催化性能。结果表明:Ag和CdS纳米粒子被成功沉积在TiO_2纳米管上;与纯TiO_2纳米管的吸收光谱相比,Ag-CdS/TiO_2NTs对光的吸收范围延伸到整个可见光区域;与纯TiO_2纳米管或CdS修饰的TiO_2纳米管相比,Ag(3)-CdS/TiO_2NTs对甲基橙脱色率最高,70 min后脱色率达100%。     

In situ Fenton reagent generated from TiO2/Cu2O composite film: a new way to utilize TiO2 under visible light irradiation

TiO2/Cu2O composite is prepared by a simple electrochemical method and coated on glass matrix through a spraying method. The obtained composite is characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of TiO2/Cu2O composite films with different ratio of TiO2 and Cu2O on photodegradation of the dye methylene blue under visible light is investigated in detail. It is found that the photocatalytic activity of TiO2/Cu2O composite film with the presence of FeSO4 and EDTA is much higher than that for the similar system with only TiO2 and Cu2O film respectively. Without the presence of FeSO4 and EDTA, there is no degradation for methylene blue. The exploration of the optimized parameters for the degradation of methylene blue by using TiO2/Cu2O composite film as catalyst under visible light was also carried out. The most significant factor is the amount of Ti02 in the composite, and the second significant factor is the concentration of FeSO4. During the degradation of methylene blue under visible light, TiO2/Cu2O composite film generates H202, and Fenton regent is formed with Fe2+ and EDTA, which is detected in this study. The mechanism for the great improvement of photocatalytic activity of TiO2/Cu2O composite film under visible light is proposed by the valence band theory. Electrons excitated from TiO2/Cu2O composite under visible light are transferred from the conduction band of Cu2O to that of Ti02. The formed intermediate state of Ti 3+ ion is observed by X-ray photoelectron spectroscopy (XPS) on the TiO/Cu2O composite film. Additionally, the accumulated electrons in the conduction band of TiO2 are transferred to oxygen on the TiO2 surface for the formation of O2- or O2(2-), which combines with H+ to form H2O2. The evolved H202 with FeSO4 and EDTA forms Fenton reagentto degrade methylene blue. Compared to the traditional Fenton reagent, this new kind of in situ Fenton reagent generated from TiO2/Cu2O composite film does not need to supply H202. It is expected to be easily recycled, which may reduce second pollution and the cost of wastewater treatment. Moreover, this TiO/Cu2O composite film with FeSO4 and EDTA provides a new way to take advantage of TiO2 under visible light.     

二氧化钛/碳纤维多孔薄膜的制备及其催化性能

以聚乙二醇(PEG)为制孔剂,通过溶胶凝胶浸渍涂覆法和烧结法将二氧化钛(TiO2)负载于经表面修饰的碳纤维(CF)上,制备多孔TiO2/CF光催化材料.采用场发射扫描电子显微镜(FE-SEM)、X射线衍射仪(XRD)表征材料的形貌和晶型结构,研究TiO2/CF光催化材料对甲基橙溶液的吸附性能,并以质量浓度为80 mg/...     

Development of an E-H2O2/TiO2 photoelectrocatalytic oxidation system for water and wastewater treatment

In this study, an innovative E-H2O2/TiO2 (E-H2O2 = electrogenerated hydrogen peroxide) photoelectrocatalytic (PEC) oxidation system was successfully developed for water and wastewater treatment. A TiO2/Ti mesh electrode was applied in this photoreactor as the anode to conduct PEC oxidation, and a reticulated vitreous carbon (RVC) electrode was used as the cathode to electrogenerate hydrogen peroxide simultaneously. The TiO2/Ti mesh electrode was prepared with a modified anodic oxidation process in a quadrielectrolyte (H2SO4-H3PO4-H2O2-HF) solution. The crystal structure, surface morphology, and film thickness of the TiO2/Ti mesh electrode were characterized by X-ray diffraction and scanning electron microscopy. The analytical results showed that a honeycomb-type anatase film with a thickness of 5 microm was formed. Photocatalytic oxidation (PC) and PEC oxidation of 2,4,6-trichlorophenol (TCP) in an aqueous solution were performed under various experimental conditions. Experimental results showed that the TiO2/Ti electrode, anodized in the H2SO4-H3PO4-H2O2-HF solution, had higher photocatalytic activity than the TiO2/Ti electrode anodized in the H2SO4 solution. It was found that the maximum applied potential would be around 2.5 V, corresponding to an optimum applied current density of 50 microA cm(-2) under UV-A illumination. The experiments confirmed that the E-H2O2 on the RVC electrode can significantly enhance the PEC oxidation of TCP in aqueous solution. The rate of TCP degradation in such an E-H2O2-assisted TiO2 PEC reaction was 5.0 times that of the TiO2 PC reaction and 2.3 times that of the TiO2 PEC reaction. The variation of pH during the E-H2O2-assisted TiO2 PEC reaction, affected by individual reactions, was also investigated. It was found that pH was well maintained during the TCP degradation in such an E-H2O2/TiO2 reaction system. This is beneficial to TCP degradation in an aqueous solution.     

A new route for degradation of volatile organic compounds under visible light: using the bifunctional photocatalyst Pt/TiO2-xNx in H2-O2 atmosphere

The bifunctional photocatalyst Pt/TiO2-xNx has been successfully prepared by wet impregnation. The properties of Pt/ TiO2-xNx have been investigated by diffuse reflectance spectra, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, a photoluminescence technique with terephthalic acid, and electric field induced surface photovoltage spectra. The photocatalytic activity of the sample was evaluated by the decomposition of volatile organic pollutants (VOCs) in a H2-O2 atmosphere under visible light irradiation. The results demonstrated that nitrogen-doped and platinum-modified TiO2 in a H2-O2 atmosphere could enormously increase the quantum efficiency of the photocatalytic system with excellent photocatalytic activity and high catalytic stability. The increased quantum efficiency can be explained by enhanced separation efficiency of photogenerated electron-hole pairs, higher interface electron transfer rate, and an increased number of surface hydroxyl radicals in the photocatalytic process. A mechanism was proposed to elucidate the degradation of VOCs over PtTiO(2-x)Nx in a H2-O2 atmosphere under visible light irradiation.     

多孔TiO2薄膜在PET纤维上的负载及其光催化性能

采用浸渍法将低温制备的TiO2溶胶在普通和碱减量PET纤维上负载成膜,并以聚苯乙烯（PS）微球为模板剂使TiO2膜多孔化,制备了一系列TiO2/PET光催化纤维。采用XRD、SEM对TiO2和纤维进行了表征,并通过对甲基橙的降解来考察其光催化性能。结果表明：溶胶经室温陈化后可得到具有较高光催化活性的纳米锐钛矿型TiO2。PET纤维上TiO2的负载率随着溶胶在浸渍液中的含量增加而增大。PET纤维的碱减量有利于TiO2的负载和光催化活性的提高,且随着TiO2负载率的增加,甲基橙降解率具有先增加后缓慢减小的趋势。当碱减量纤维的TiO2负载率为4.2%时,光催化活性最好。利用PS为模板剂使TiO2薄膜多孔化可以进一步提高光催化纤维的比表面积和吸附能力,从而提高光催化活性。     

Degradation of benzene over a zinc germanate photocatalyst under ambient conditions

A rod-shaped Zn2GeO4 photocatalyst has been successfully prepared by a surfactant-assisted hydrothermal method. The photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, UV/vis, N2 adsorption-desorption, and FTIR techniques. The photocatalytic activity of the sample was evaluated by the decomposition of benzene in the gas phase under UV light illumination and was compared with that of bulk Zn2GeO4, commercial titania (Degussa P25), and Pt/P25. The results revealed that the Zn2GeO4 nanorods had the best photocatalytic activity for mineralizing benzene to CO2 among the catalysts examined. No obvious deactivation of Zn2GeO4 nanorods was observed during the prolonged operation of 140 h. It was found that the Zn2GeO4 was also more active and stable than TiO2-based catalysts toward photocatalytic decomposition of other volatile aromatic pollutants (e.g., toluene and ethylbenzene).