共查询到20条相似文献,搜索用时 15 毫秒
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报道了两种促进超细TiO2粒子金红石化的新方法-微波加热水解法和添加剂法。用X射线衍射仪和TEM对样品进行了分析,在不引入任何金属离子、不烧结的前提下显著地提高了产品金红石的含量。 相似文献
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The adsorption of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) on a rutile TiO(2)(011)-(2 × 1) surface is studied using ultra-high vacuum scanning tunneling microscopy. The self-assembly process is dominated by the fine interplay between the lateral intermolecular interactions and the binding to the substrate. By means of temperature-induced change in the adsorption configuration and the activation of diffusion, the molecules are assembled into one-dimensional chains oriented along the [Formula: see text] crystallographic direction. 相似文献
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Jingwei Xie Xiaohua Lu Yu Zhu Chang Liu Ningzhong Bao Xin Feng 《Journal of Materials Science》2003,38(17):3641-3646
Since potassium hexatitanate whisker is often used for the filler of composites or as a catalyst, its surface is very important. In this paper the surface morphology and structure of potassium hexatitanate fiber has been observed by AFM. The potassium hexatitanate fiber shows that its surface has different lamellas. In addition, we obtained the temperature dependence of the linear expansive ratios along a, b, c 3 directions of the cell by molecular dynamics simulation. The simulation result shows that the linear expansive ratios along the 3 directions are almost the same. Therefore, the periodical surface structure is not generated by the shrinkage along 3 directions in the cooling process of the K2O·6TiO2 whisker preparation. The surface structure is believed to be related to the mechanism of crystal growth of the K2O·6TiO2 whisker and is consistant with the liquid melt inducing model [22]. 相似文献
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杂多酸(盐)掺杂TiO2制备新型复合光催化剂的研究进展 总被引:2,自引:0,他引:2
TiO2光催化剂由于具有光催化能力强、降解彻底、无二次污染等优点,在污染物降解方面发挥着重要的作用,近年来杂多酸(盐)掺杂TiO2复合光催化剂更是由于其优异性能而得到日益广泛的关注.介绍了常用的杂多酸种类,阐述了杂多酸(盐)掺杂TiO2进行光催化降解有机物的过程及原理,即杂多酸(盐)可以捕获TiO2在光催化下产生的电子,使载流子扩散长度增大,延长电子和空穴的寿命,抑制电子空穴的复合等.同时介绍了目前常用的溶胶-凝胶法、浸渍法、离子交换法、水热合成等掺杂方法,讨论了各种因素如杂多酸(盐)浓度、有机物的浓度、材料的结构等对复合催化剂光催化活性的影响因素,并展望了今后的发展趋势. 相似文献
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采用离子辅助蒸发的方法,以不同配比的Ta2O5和TiO2混合物为初始膜料在K9玻璃上制备了TiO2-Ta2O5混合薄膜,并对其透射性能和光学常数进行研究。实验结果表明,薄膜在可见光范围内的平均透射率在82%以上,并随着Ta2O5含量的增加而增加;薄膜的折射率在1.80~2.07范围内变化(550nm)。对同-Ta2O5含量的薄膜来说,退火后TiO2薄膜和80TiO2—20Ta2O5薄膜的折射率较退火前提高,而90TiO2-10Ta2O5薄膜的折射率较退火前降低。 相似文献
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Jiaojiao Ye Yunfei Liu Yinong Lu Jianxiang Ding Chengjian Ma Hao Qian Zhenglei Yu 《Journal of Materials Science: Materials in Electronics》2014,25(10):4632-4637
The energy-storage properties of SrTiO3-doped (15, 20, 25, and 30 mol%) 0.80Bi1/2Na1/2TiO3–0.20Bi1/2K1/2TiO3 lead-free antiferroelectric ceramics were investigated by two-step sintering method. The ceramics with higher SrTiO3 content had smaller grain sizes and a more homogeneous distribution. About 25 mol% SrTiO3 doping induced antiferroelectric properties, showing a typical double hysteresis loops, accompanied by a large energy density. The first sintering temperature of the ceramics had main impact on the relative density, and the high relative density possessed large external breakdown strength. The optimum electrical performances with a low remanent polarization (Pr = 1.9 μC/cm2), a low coercive field (Ec = 1.7 kV/cm) and a large energy density (W = 0.97 J/cm3) at 10 Hz were obtained at 1,190 °C for a SrTiO3 content of 25 mol%. 相似文献
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《International Journal of Inorganic Materials》1999,1(2):175-180
SiO2–TiO2 porous materials containing anatase as the crystalline TiO2 phase have been synthesized by heat-treatment at 650°C of gels formed from methanolic solutions of (2-hydroxyethyl)trimethylammonium silicate, which had the cubeoctameric silicate structure in its backbone, and titanium bis(triethanolaminate). Gelation time of the solutions ranged from 12 to 250 h, which depended on the Ti-to-Si atomic ratio within the limits of 0.1 and 2.0. However, addition of a small amount of H2O drastically reduced the gelation time. Hydrolysis of the titanium compound seemed to promote the sol–gel reaction. A gel prepared from the methanolic solution with a Ti-to-Si ratio of 1.0 gave the porous substance with the highest BET surface area (496 m2 g−1) by the heat-treatment, and the average pore diameter of the substances increased with increasing Ti-to-Si ratio. The product prepared from a solution with an extra amount of H2O revealed similar porous properties to that prepared without the addition of H2O, indicating that the addition of H2O to the starting solution is effective for producing the porous materials in a shorter reaction time. 相似文献
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通过固相反应法合成了具有光致变色性质的La(2-x)/3(Ag(0)1-2x/3Ag(I)x)TiO3(简称Ag-LST)钙钛矿结构复合氧化物粉体,采用XRD、XPS、ICP和SEM等实验技术对Ag-LST进行了表征.结果表明,Ag-LST具有立方晶相钙钛矿结构,其表面层元素组成为Ag:La:Ti=0.45:0.60:1.00.研究了Ag-LST的光致变色性质,在紫外光(300W汞灯)下照射Ag-LST 1min,样品的颜色从棕黄色转变为蓝紫色;在可见光(500W氙灯)下照射Ag-LST 1h,样品恢复为原来的棕色.Ag-LST的光致变色性质可能与Ag(0)-Ag(I)相互转换有关. 相似文献
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纳米Cu2+/TiO2抗菌膜对禽流感病毒(H9N2)的灭活效应 总被引:1,自引:0,他引:1
利用病毒滴度测定和MDCK细胞电镜观察法,初步探讨了在365nm的黑光灯(UV)照射下,纳米Cu2+/TiO2抗菌膜对禽流感病毒(H9N2)的光催化灭活效应,并分别考察了UV强度、UV照射时间以及H9N2病毒量对H9N2病毒光催化灭活效应的影响.实验结果表明,在365nm黑光灯的照射下,纳米Cu2+/TiO2抗茵膜对H9N2病毒具有显著的灭活效应,在UV强度为0.5mW/cm2、UV照射时间为2.5h、病毒量为0.1ml时,H9N2病毒的灭活率达到了100%.研究结果表明,纳米Cu2+/TiO2抗菌膜在抑制禽流感(H9N2)病毒在环境媒介中的扩散与传播方面有潜在的应用价值. 相似文献
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The magnetic, electrical, catalytic, and photocatalytic properties of ZrO2–TiO2materials were studied. The ZrO2–TiO2system was shown to contain ZrO2-, TiO2, and ZrTiO4-based solid solutions. Procedures for the preparation of high-activity ZrO2–TiO2photocatalysts and photostable pigments were developed. 相似文献
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基于密度泛函理论(DFT)中广义梯度近似(GGA)下的BLYP、PBE泛函,研究了TiCl_4、O_2在金红石型TiO_2(110)晶胞表面上不同位点的吸附,以及TiCl_4和O_2分子共吸附后在最稳定吸附构型上的解离过程。结果表明,O_2分子在TiO_2(110)晶胞表面上最稳定的吸附位点为氧空位,O_2分子吸附在氧空位后,其中一个O原子与Ti5c原子成键形成桥位氧(O_(bri));另一个O原子形成O增原子(O_(ada)),吸附能为-11.58 kJ/mol,Mulliken电荷布居分析表明O_2分子向表面转移了0.12 eV电荷;TiCl_4分子在TiO_2(110)晶胞表面上最稳定的吸附位点为桥氧位,吸附能为-48.64 kJ/mol,Mulliken电荷布居分析表明TiCl_4分子向晶胞表面转移了0.26 eV电荷;TiCl_4与O_2在各自最佳的吸附位上吸附后,TiCl_4分子在O增原子(O_(ada))的作用下按—TiCl_4→—TiCl_3→—TiCl_2→—TiCl的主要路径发生解离,在TiCl_4分子解离过程中,正反应方向上的活化能垒均小于逆反应方向上的活化能垒,说明TiCl_4分子的解离过程为放热反应。 相似文献
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采用平面波超软赝势方法研究了Pt和Au修饰锐钛矿型TiO2(101)面的结构稳定性及电子结构。结果显示贵金属原子在TiO2(101)符合化学计量比的条件下, 在其表面的吸附作用不强, 对电子结构的影响也较小。但是发现在富O条件下, Pt和Au原子容易吸附在表面Ti空位的位置, 与Au原子不同, Pt原子有从TiO2表面扩散进入体相晶格中的趋势。而在富Ti条件下, Pt和Au原子容易吸附在O1空位的位置。对可能存在的几种空位缺陷吸附模型进行了电子结构的计算。结果表明: 空位缺陷的产生不仅有利于Pt和Au原子“湿化”TiO2(101)表面, 也有利于带隙中产生贵金属原子的5d杂质能级。 相似文献
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为了改善Ni-P-纳米TiO2化学复合镀镀层的耐腐蚀性能和沉积速度,采用失重腐蚀法、磁力测厚仪和电化学方法,研究了工艺、配位剂、纳米TiO2溶胶含量对Ni-P-TiO2(溶胶)纳米化学复合镀镀层的沉积速度、腐蚀速率、孔蚀电位的影响,得出其较优工艺配方为:25.0g/L硫酸镍、25.0g/L次磷酸钠、15.0g/L乙酸钠、15.0g/L硼酸,1h,pH值5.5~6.5,80℃,100r/min,12.5mL/L纳米TiO2溶胶。此外,研究显示可用配位剂硼酸代替传统的乳酸。结果表明,在盐腐蚀介质中,Ni-P-纳米TiO2(溶胶)镀层的耐腐蚀性能比Ni-P镀层提高10多倍,在碱性腐蚀介质中提高约1倍,而在酸性介质中耐蚀性比Ni-P镀层略差。 相似文献
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