摘要二氧化钛是一种白色固体或粉末状的两性氧化物，具有许多优良性能，被 广泛的应用于各大领域。在自然界中二氧化钛存在三种不同形态的矿物结构， 分别是金红石型、锐钛矿型和板钛矿型。其中锐钛矿型二氧化钛因其良好的光 催化性能，可用于环境污染物的催化降解。81232

本文介绍了通过溶胶—凝胶法制备了纳米二氧化钛粉末和负载银的纳米二 氧化钛粉末的实验过程。煅烧后得到四份二氧化钛粉末，然后分别以这四份二氧 化钛粉末为核心，进行改性接枝制备了四份无溶剂的纳米流体。通过扫描电子显 微镜观察了制得的粉末的表面形貌和尺寸粒度，表明粉末不够均匀和规整，粒度 大约在 10µm -100µm，经分析后表明粉末成分较纯净，并且成功负载银，银含量 达到 2%。XRD 衍射和紫外可见光谱表证后，进一步确定了银的存在，并发现了 煅烧后的二氧化钛粉末晶型为锐钛矿型。利用红外光谱分析，得知制得的纳米粒 子都已经过改性接枝是符合预期要求的成品。通过 TG 分析后，明显的看出煅烧 后的粉末制备的纳米流体其热性能更加优越，结构更加稳定。

最后通过滴定法，定量的分析了二氧化钛无溶剂纳米流体的光催化性能， 并与标准商品样进行对比。发现在自然光的条件下，二氧化钛的纳米流体催化 分解了 39。02%的甲醛，仅低于商品样 7。5 个百分点。证明了二氧化钛无溶剂纳 米流体具备较好的光催化性能，同时纳米流体还有流动性好，表面能高，绿色 环保，可溶性好等优良特点，其未来的前景将是不可估量的。

毕业论文关键词：二氧化钛；改性；无溶剂纳米流体；光催化性能

Abstract Titanium dioxide is a kind of white solid or powder oxide, which has many excellent properties and has been widely used in many fields。 In nature there are three different forms of titanium dioxide mineral structure, namely rutile, anatase and brookite。 Due to its excellent photocatalytic performance, anatase titanium dioxide can be used for the catalytic degradation of environmental pollutants。

In this paper, we introduce the experimental process of preparing nano titanium dioxide powder and silver-loaded nano titanium dioxide powder by sol-gel method。 After calcination, four types of TiO2 powder are obtained, and then the four non solvent nano fluids are prepared by modified grafting with the four powder as the core。 By scanning electron microscopy observed of powder surface morphology and size, we find that powder is not uniform and regular, and particle size is about 10µm to 100µm。 The powder composition was confirmed and silver content of 2% is successfully loaded through analysising。 XRD diffraction and UV Vis spectra shows the presence of silver was confirmed, and the crystal form of the calcined TiO2 powder was anatase。 Using infrared spectroscopy analysis, it is found that the prepared nanoparticles had been modified by grafting to meet the expected requirements of the finished product。 it is obvious that the nano fluid prepared by Calcined powder has superior thermal performance, and the structure is more stable through TG analysising。

In the end, we analyzed the photocatalytic activity of titanium dioxide solvent free nano fluid quantitatively by titration method, and compared with the standard sample。 We find that Under the conditions of natural light, the titanium dioxide nano fluid catalytic decomposes 39。02% of formaldehyde, only 7。5 percentage points lower than the sample。 It is proved that the titanium dioxide nano fluid has better photocatalytic activity。 At the same time, the nano fluid has good mobility, high surface energy, green environmental protection, good solubility and other excellent features, its future prospects will be immeasurable。