TiO_2气敏元件的空燃比敏感特性

通过气氛模拟实验,研究了TiO_2气敏元件的空燃比(A/F)敏感特性;借助气体边界层模型分析了临界值(A/F)_c的偏移现象。测定了气孔率、催化剂等对气敏速度的影响。采用EPMA技术,分析了元件表面污染状态对其使用寿命的影响。并初步探讨了掺杂对TiO_2电性能的影响以及TiO_2的自身催化氧化过程。     

碳纳米管/TiO2电极光电催化测定耐兰方法探讨

自合成二氧化钛-碳纳米管（TiO2一CNT）复合催化剂，用Nafion溶液把CNT—TiO2固定到玻碳电极上制成CNT—TiO2／GC修饰电极，以耐兰染料为测定对象，进行光电化学响应研究．结果表明，在pH7．2的磷酸盐缓冲液中，示差脉冲伏安法（DPV）测定，分散兰1于-0．4V（vs Ag／AgCl）处产生良好的阴极还原峰，电极对耐兰染料的吸附过程符合Langmuir吸附，其光电响应值高于碳糊／TiO2电极．高光电响应意味着复合材料制成电极后，对有机染料废水的检测限更低，灵敏度更高。     

The Preparation of Porous Activated Slag Granules/TiO_2 Photocatalyst and Its De-NO_x Performance

The porous structure and honeycombed structure of granulated blast furnace slag formed by alkali activation (AGBFS) can be used as a promising photocatalysts substrate for the photocatalytic removal of atmospheric or water pollutants.In this study,photocatalytic activated slag granules were synthesized by loading TiO_2 on AGBFS with immersion method.The physicochemical properties and NO_x removal performance of activated slag granules/TiO_2 photocatalysts were studied by X-ray diffraction (XRD),scanning electron microscope (SEM) and photocatalytic performance test.The effects of slag particle sizes and nano-TiO_2 loading concentrations on photocatalytic efficiencies of NO_x removal were also investigated.It was found that the De-NO_x performance of activated slag granules/TiO_2 photocatalyst increased with the increasing of slag particle size in low TiO_2 loading concentration situation,while increasing the TiO_2 loading concentration would result in the opposite De-NO_x performance as slag size increased.Nevertheless,for the same size activated slag,the photocatalytic efficiency of activated slag granules/TiO_2 photocatalyst gradually improved with the increase of loading concentration of TiO_2.     

B4C/TiO2/Al复合材料制备及其性能

采用热压法制备了B4C/TiO2/Al复合陶瓷材料，试验结果表明，TiO2和Al的加入，使得B4C/TiO2/Al复合材料的硬度、抗弯强度和断裂韧性比纯B4C陶瓷材料有较大程度的提高；而且，添加相促进了复合材料的烧结.利用热力学和X射线衍射分析研究烧结过程中的化学反应，分析结果表明，复合材料中没有发现TiO2，Al，Al2O3；同时在复合材料中出现了TiB2，因为在热压过程中TiO2与B4C反应生成TiB2.分析了B4C/TiO2/Al复合陶瓷材料的微观结构和增韧机理.     

管载二氧化钛凝胶镀膜光催化清除乙烯气体

报道了用sol gel方法在玻璃管上制备二氧化钛薄膜对清除乙烯气体的光催化实验,研究了二氧化钛一次镀膜对乙烯浓度随催化反应时间的变化关系。结果发现,二氧化钛镀膜有较好的清除乙烯的效果,当反应进行到46h时乙烯气体的色谱峰完全消失,即乙烯气体已经被完全清除掉,对相同处理条件下的二氧化钛粉体做XRD分析知该条件下的二氧化钛为锐钛矿晶型。     

TiO2/SiO2复合气凝胶的制备研究

采用溶胶-凝胶方法制备TiO2/SiO2复合气凝胶,利用低表面积的溶剂进行替代、分级陈化和干燥,形成较为完善的网络结构,使得TiO2/SiO2复合气凝胶能够非超临界制备.所制得的复合气凝胶孔径20~40 nm,比表面积200~400 m2/g,孔体积1~2 cm3/g.     

玻璃管载二氧化钛粉体对乙烯气体的光催化效应

报道了玻璃管上负载光催化TiO2粉体对清除乙烯气体的光催化的实验研究。结果发现，玻璃管载二氧化钛粉体有较好清除乙烯的效果，当反应进行到45h时乙烯气体的色谱峰完全消失，即乙烯气体已经被完全清除掉．对相同处理条件下的二氧化钛粉体做XRD分析得知该条件下的二氧化钛为锐钛矿晶型。在紫外区域作吸收曲线发现光催化TiO2紫外吸收边发生蓝移，产生量子效应。     

玻璃管载二氧化钛粉体对乙烯气体的光催化效应

报道了玻璃管上负载光催化TiO2粉体对清除乙烯气体的光催化的实验研究。结果发现,玻璃管载二氧化钛粉体有较好清除乙烯的效果,当反应进行到4.5h时乙烯气体的色谱峰完全消失,即乙烯气体已经被完全清除掉,对相同处理条件下的二氧化钛粉体做XRD分析得知该条件下的二氧化钛为锐钛矿晶型。在紫外区域作吸收曲线发现光催化TiO2紫外吸收边发生蓝移,产生量子效应。     

Degradation of Formaldehyde and Benzene by TiO_2 Photocatalytic Cement Based Materials

A novel photocatalytic cement based material was prepared. The distribution of TiO_2 on the surface of cement was characterized by scanning electron microscope(SEM) and X-ray diffraction(XRD), which showed the relationship of photocatalysis and presence of TiO_2. TiO_2 also had an impact on cement hydration, which was studied by thermal analysis. With 300 W UV illuminations, formaldehyde and benzene were degraded efficiently by the prepared photocatalytic cement based materials. 15wt% TiO_2/cement showed the highest degradation efficiency and capability. The results show that formaldehyde and benzene can be degraded within 4 and 9 hours, respectively. Besides, inorganic ions can induce TiO_2 agglomeration. As a result, the presence of inorganic ions in cement is unfavorable for degradation. The photocatalytic cement based materials were fabricated and the degradation efficiency of formaldehyde was measured on building roof under sunlight illumination. Formaldehyde in glass chamber can be degraded thoroughly within 10 days.     

电流密度对TA2纯钛微弧氧化多孔陶瓷膜的影响

采用恒定电流密度控制方法,在碳酸钠-硅酸钠溶液体系中制备TA2纯钛微弧多孔氧化陶瓷膜,研究了阳极电流密度ja和阴/阳极电流密度比jc/ja对陶瓷膜的厚度和相结构的影响。实验发现,陶瓷膜的厚度随ja和jc/ja的增加都存在一个峰值;提高阳极电流密度,陶瓷膜中的金红石相TiO2的含量增加,而增加阴/阳极电流密度比,陶瓷膜中金红石相TiO2的含量减少,但有利于锐钛矿相TiO2含量的增加。     

陶瓷填料与光催化剂对反应器效率的影响

目的了解陶瓷填料与光催化剂对气体放电-光催化反应器净化效率的影响.方法通过理论计算、吸附实验和电容测试等方法对气体放电-光催化反应器所用的A、B两种陶瓷填料以及附着纳米TiO2光催化剂的B类陶瓷填料物理特性进行了分析.结果A类陶瓷的介电常数计算值大于B类陶瓷的计算值;介电常数的实验值为A类陶瓷相似文献   

溶胶-凝胶法制备纳米TiO2/SnO2复合微粒的研究

以有机、无机盐为原料，通过加入稳定剂、催化剂，采用溶胶-凝胶法制备TiO2、SnO2、TiO2／SnO2纳米微粒，采用XRD、SEM和XPS等技术对粒子性能进行分析．结果表明：TiO2／SnO2粒子主要由锐钛矿型TiO2和金红石型SnO2组成，与纯TiO2、SnO2相比，TiO2／SnO2微粒的粒度小，分布均匀，不团聚。     

TiO2/ZnO及掺Ag+水溶胶抗紫外性能研究

以钛酸丁酯和乙酸锌为前驱物,制备TiO2-ZnO水溶胶.研究了TiO2与ZnO的掺杂比例和掺银量对溶胶抗紫外性能的影响.当TiO2与ZnO的掺杂比例改变时,随着ZnO比例增加,溶胶抗紫外性能有所下降;对于掺银TiO2/ZnO溶胶,当掺银量逐渐增加时,掺杂溶胶的紫外吸收性能有所增强.     

医用NiTi合金表面双层生物活性薄膜的制备及表征

采用溶胶-凝胶法在NiTi合金基体上制备出TiO2-SiO2-HAP梯度生物活性薄膜,通过仿生合成进一步制备了TiO2-SiO2-HAP/HAP双层生物活性薄膜。SEM、XRD和FTIR对复合薄膜的测试结果表明,外层的HAP薄膜呈多孔网状;电化学腐蚀测试表明,与TiO2-SiO2-HAP梯度生物活性薄膜相比,TiO2-SiO2-HAP/HAP双层生物活性薄膜的抗腐蚀性进一步增强。     

掺杂金属卟啉的TiO_2薄膜对活性艳红X-3B染料的光催化降解性能

采用溶胶凝胶的方法,将具有高光敏性的四(对羟基)苯基锌卟啉(ZnTHPP,下简称锌卟啉)在钛酸丁酯[Ti(OBu)4]水解的条件下均匀嵌入到了TiO2无机网络中,又采用旋涂法制备了ZnTHPP/TiO2复合薄膜。利用UV Vis吸收光谱对薄膜的紫外可见光吸收性质进行了研究,结果表明锌卟啉的加入能有效的拓宽TiO2的可见光吸收范围。通过光催化降解活性艳红X 3B染料实验,对所制备的ZnTHPP/TiO2复合薄膜的光催化活性进行了考察,研究发现以ZnTHPP/TiO2作为光催化剂对活性艳红X 3B染料能有效的降解,表现出了较好的可见光催化活性。     

Preparation of PDVB/TiO_2 composites and the study on the oil-water separation and degradation performances

The traditional superhydrophobic materials are not ideal for treating residual pollutants after oil-water separation. In this paper, a simple and economical method was developed for the fabrication of multi-functional superhydrophobic materials PDVB_x/TiO_2 composites, through in situ polymerization. The performance of the superhydrophobic composite was studied. The results showed that the low surface energy of PDVB_(2.5)/TiO_2 composite with the micro-nano scale roughness would result in excellent superhydrophobicity. In addition, the PDVB_(2.5)/TiO_2 composite exhibits optimum effect on the degradation of methyl orange(MO) with the degradation efficiency of 97.8%. What is more, the applications of the composite materials could be expanded to other fields, such as the degradation of drug ciprofloxacin hydrochloride(CIP). Finally, we expanded the application of the PDVB_x/TiO_2 composites to tribology, and found its excellent performance in reducing wear and antiwear.     

Coexistence of antiferromagnetic and ferromagnetic in Mn-doped anatase TiO2 nanowires

A series of Mn-doped TiO_2 nanowires (NWs) were prepared by hydrothermal method at the mole fraction of Mn changing from 0 to 12.0%. X-ray powder diffraction (XRD) analysis shows that all the samples have pure anatase structure. SEM and TEM studies show that the diameter and the length of the Mn-doped TiO_2 NWs are larger than those of the undoped TiO_2 NWs. Energy dispersive X-ray spectroscopy (EDX) reveals that the samples are composed of Ti, Mn and O. According to magnetization measurements, all samples show ferromagnetic behavior, but only the undopedTiO_2 NWs are completely ferromagnetic with a saturated magnetization about 1.0 mA·m~2/kg. Mn-doped TiO_2 samples exhibit antiferromagnetic and ferromagnetic (AF-FM) behaviors simultaneously. Photoluminescence (PL) spectra demonstrate the existence of MnO_2 sublattice. These observations indicate that an AF-WF crossover is induced by the coexistence of TiO_2 sublattice and MnO_2 sublattice.     

CdS、Ag^＋掺杂改性纳米TiO2光催化降解甲基橙动力学研究

在探索纳米TiO2光催化降解甲基橙的最佳条件后,对纳米TiO2及其改性光催化剂CdS/TiO2、Ag＋/TiO2光催化降解甲基橙性能进行了动力学研究,结果表明：纳米TiO2及其改性的CdS/TiO2、Ag＋/TiO2的光催化反应符合动力学一级反应规律;三种光催化反应剂的光催化均存在诱导期,其中纳米TiO2光催化反应诱导期最长,其次是Ag＋/TiO2光催化反应,而CdS/TiO2光催化反应诱导期最短;光催化反应降解甲基橙效率是：TiO2光催化反应最低,其次是Ag＋/TiO2,CdS/TiO2效率最高.     

纳米二氧化钛表面的化学改性及表征

研究了利用偶联剂A，偶联剂A和B复合两种改性纳米二氧化钛的方法，并通过FT—IR，SEM等手段表征化学改性产物的结构和改性后纳米二氧化钛的分散性能。结果表明偶联剂A和偶联剂B与二氧化钛表面羟基发生化学偶联反应，使二氧化钛表面被偶联剂包覆，从而使二氧化钛改性产物在甲苯中具有良好的分散性能。     

Kinetics analysis of Ni-TiO_2 composite system during initial stages of electro-crystallization

The initial stage of Ni-TiO_2 composite system electrodeposition on glassy carbon electrode from an acidic solution of nickel sulfate was investigated using cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). Analysis of current density-time transients was performed using the nonlinear fitting procedure and electrochemical impedance spectroscopy was simulated by Z-view software. Besides, the surface morphology of Ni-TiO_2 co-deposition at the initial stage was observed by scanning electron microscopy (SEM). The results show that, in the case of low overpotential (-790 mV vs SCE), the presence of TiO_2 particles in the plating bath makes the nucleation relaxation time tmax decreased clearly. Meanwhile, the electro-crystallization of Ni-TiO_2 system follows a Scharifker-Hills (SH) progressive nucleation/growth mechanism. While in the case of higher overpotential, the presence of the TiO_2 particles in solution makes the nucleation relaxation time tmax increased. At -850 mV (vs SCE), the co-deposition of Ni-TiO_2 system meets SH instantaneous nucleation/growth mechanism. The results of impedance spectra show that the appearance of the characteristic inductive loops represents the nucleation/growth of nickel and the presence of TiO_2 particles reduces the charge transfer resistance of solution. The SEM observation confirms that TiO_2 particles can be considered as favorable sites for nickel nucleating.