TiCl4为原料掺碳二氧化钛的可见光催化活性

为拓展二氧化钛对可见光的响应,采用水解法和其它步骤制备了碳掺杂二氧化钛粉末。用X射线衍射和紫外-可见光漫反射吸收光谱以及X射线光电子能谱对制备的样品进行了表征,对可见光照射下的光催化活性进行了测试,并考察了光催化的重复性。结果表明：碳掺杂致使二氧化钛在可见光区的光吸收增强,在降解甲基橙的实验中表现出良好的可见光催化活性。     

钴掺杂二氧化钛光催化剂制备及光催化活性

采用溶胶-凝胶法制备了纯二氧化钛和不同钴掺杂量的二氧化钛复合纳米粒子。并用XRD、UV-Vis对样品组织结构进行了表征。以甲基橙（OM）的光催化降解为探针反应,评价了可见光催化活性,研究了不同热处理温度、不同钴掺杂量对二氧化钛光催化性能的影响。确定了最佳钴掺杂量和热处理温度分别为1%（物质的量分数）和600  ℃。在此条件下,钴的掺杂对二氧化钛的相变有很大的抑制作用,并使其光谱响应范围向可见光区拓展。与未掺杂的二氧化钛相比较,经钴掺杂的二氧化钛具有更高的催化性能。     

掺铁纳米二氧化钛的的制备及光催化性能

以钛酸丁酯为原料,采用溶胶-凝胶法制备出了掺杂Fe的纳米二氧化钛粉体。采用紫外-可见漫反射吸收光谱（DRS）和X射线衍射（XRD）技术对其进行表征,并对Fe掺杂浓度、煅烧温度、煅烧时间对纳米TiO2光学活性的影响进行了研究。研究结果表明,掺杂0.5%Fe,煅烧温度500℃,煅烧时间2h改性的粉体其可见光范围的吸收明显增强,降解邻氨基苯酚的能力明显提高,5h后可达85%以上。     

镍掺杂二氧化钛催化剂的制备及其光催化性能

采用溶胶-凝胶法制备了镍离子掺杂的二氧化钛光催化材料,利用靛蓝胭脂红染料溶液为目标污染物在可见光下将其光催化降解,研究了不同Ni掺杂Ti O2催化剂的光催化活性。重点研究了不同镍掺杂浓度和煅烧温度,表面状态等对镍掺杂二氧化钛催化剂的影响,其中镍的掺杂浓度为1%,经过400℃煅烧的催化剂的效果最好,在可见光下40min就可以将10mg/L的靛蓝胭脂红溶液降解完。     

二氧化硫脲为硫源制备硫掺杂二氧化钛及其光催化活性

以钛酸四丁酯为TiO2的前驱物,二氧化硫脲为掺杂硫的源物质,采用溶胶-凝胶法制备了掺硫改性的TiO2光催化剂。采用XRD对制备的掺硫二氧化钛结构进行了表征,探讨了溶胶-凝胶制备工艺、硫掺杂量及催化剂煅烧温度对该催化剂光催化活性的影响。结果表明,掺硫改性的TiO2经600℃煅烧后光催化活性有了明显提高,且硫的掺杂有一个最佳值,即二氧化硫脲的掺杂质量百分数为4%。经掺硫改性后的TiO2在可见光区具备更强的光催化活性,在波长不低于400nm的可见光作用下,对亚甲基蓝的4 h降解率最高可达89.5%。     

用水量对溶胶-凝胶法制备氮掺杂纳米二氧化钛的影响

采用两种用水量的溶胶-凝胶工艺制备了氮掺杂二氧化钛(N-TiO2)纳米颗粒粉末,对样品进行了X射线衍射、透射电子显微镜、X射线光电子能谱及紫外-可见漫反射谱分析,并以甲基橙的光催化降解实验研究了样品的可见光催化性能。结果表明:采用用水多的溶胶-凝胶工艺可获得可见光催化活性高的N-TiO2,且N-TiO2的颗粒粒径较小;由于溶胶中过量的N掺杂剂可在N-TiO2前驱体凝胶离心分离时被去除,可进行较低温度的煅烧,易于获得N掺杂浓度较高的N-TiO2。另外,采用用水多的工艺时,氮掺杂剂对TiO2颗粒的氮化及凝胶化过程也有很大的影响,有些含氮化合物作为掺杂剂可能会明显降低N-TiO2的可见光催化活性。     

石墨烯-二氧化钛纳米管催化剂的光解水制氢性能研究

为改善能源短缺,对新型光催化水解制氢材料进行了研究。通过改进Hummer法制备氧化石墨,溶胶-凝胶法制备锐钛矿型二氧化钛,采用浓碱法制得石墨烯-二氧化钛纳米管催化剂,考察了不同石墨烯的掺杂量对催化活性的影响。经过光解水制氢实验发现,掺杂不同质量分数石墨烯的催化剂催化活性得到了进一步提高,其中掺杂量为1%的产氢活性最好,产氢速率是纯二氧化钛纳米管的2. 5倍。通过BET、XRD、UV以及FT-IR等方法对催化剂进行了表征。结果表明,石墨烯与二氧化钛纳米管成功复合,并且石墨烯的掺杂在一定程度上提高了催化剂的BET比表面积;催化剂对可见光的响应范围得到进一步扩大,这为催化剂光解水制氢性能的提高提供了有力的条件。     

铅-二氧化钛薄膜的制备与光催化性能研究

以钛酸丁酯为前驱体,醋酸铅为铅物种掺杂给体,采用溶胶-凝胶法制备经铅掺杂改性的二氧化钛溶胶,利用浸渍提拉法在普通玻璃片上制备铅-二氧化钛薄膜,利用X射线衍射（XRD）及扫描电镜（SEM）测试手段对制备的样品进行表征,考察煅烧温度、掺铅量等影响因素。以甲基橙溶液为模拟污染物,30 W紫外灯为光源,考察了铅-二氧化钛薄膜的光催化活性。研究结果表明,掺杂适量的铅离子可以促进二氧化钛锐钛矿相含量的增加及晶粒尺寸的减小;随着煅烧温度的升高,铅-二氧化钛的结晶度提高,复合薄膜表面的二氧化钛颗粒形貌逐渐变为规则形状。当煅烧温度为600 ℃、铅质量分数为0.3%时,复合薄膜具有较好的光催化活性。     

多种光源下氮掺杂TiO_2光催化降解染料废水的研究

以尿素为氮源,采用溶胶-凝胶法制备了氮掺杂纳米TiO2粉末,以甲基橙溶液为模拟染料废水,分别在可见光、模拟太阳光和紫外光条件下,研究了氮掺杂纳米TiO2光催化降解染料废水的性能。结果表明:氮掺杂可以提高TiO2的可见光催化活性;氮含量和煅烧温度对氮掺杂TiO2光催化活性影响较大,n(N)∶n(Ti)为10%且经500℃煅烧的氮掺杂TiO2在可见光和模拟太阳光下均具有最佳的光催化活性;然而在紫外光下,氮掺杂TiO2的光催化活性低于未掺杂的TiO2样品。     

碳纳米材料掺杂二氧化钛纳米棒催化剂制备方

正本发明公开了一种碳纳米材料掺杂二氧化钛纳米棒催化剂制备方法。先分别制备出二氧化钛纳米棒和碳纳米材料,再采用冷凝回流的方法完成碳纳米材料掺杂到二氧化钛纳米棒的制备。在制备过程中,通过控制二氧化钛纳米棒中碳的不同体积比,能够使掺杂后光催化材料对可见光具有响     

不同方法制备硫掺杂TiO2及其可见光催化性能研究

采用水热法和焙烧法分别制备了硫掺杂纳米TiO₂,通过扫描电子显微镜、X射线光电子能谱和紫外可见漫反射光谱进行了表征,以水体中的甲基橙（MO）为模拟污染物,研究了硫掺杂纳米TiO₂ 的可见光光催化性能。结果表明,2种不同制备方法得到的硫元素掺杂TiO₂均表现出可见光活性。硫元素在TiO₂中分别取代了O₂和Ti的位置,改变了TiO₂原来的能带结构,形成新的杂质能级,从而使TiO₂ 的吸收区间由紫外拓展到可见光区。     

Mechanochemical Synthesis of Visible-light Induced Photocatalyst with Nitrogen and Carbon Doping

Nitrogen and/or carbon doped titania photocatalysts were prepared by a novel mechanochemical method. The prepared powders possessed two absorption edges around 400 and 540 nm wavelengths and showed excellent photocatalytic ability for nitrogen monoxide oxidation under visible light irradiation. Under the irradiation of visible light of wavelength >510 nm, 37% of nitrogen monoxide could be continuously removed by the carbon and nitrogen co-doped titania prepared by planetary ball milling of P-25 titania-10% hexamethylenetetramine mixture followed by calcination in air at 400?C.     

Preparation of cerium and nitrogen co-doped titania hollow spheres with enhanced visible light photocatalytic performance

N,Ce-codoped titania hollow spheres were prepared using carbon spheres as template and using N,Ce-codoped titania nanoparticles as building blocks. The N,Ce-codoped titania nanoparticles were synthesized at low temperature. The prepared hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and UV-Vis diffuse reflectance spectrum (DRS). The effect of N and Ce content on the physical structure and photocatalytic properties of the as-prepared hollow sphere samples was investigated. The mechanism of photocatalytic degradation of dyes under visible light irradiation was also discussed.     

Synthesis and characterization of carbon-doped titania as a visible-light-sensitive photocatalyst

The synthesis and use of carbon-doped TiO₂ particles in photocatalysis under visible light are demonstrated. The carbon-doped titania with its mesoporous structure was prepared by chemical modification and characterized by several techniques including X-ray diffraction, transmission electron spectroscopy (TEM), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance spectra (EPR), and diffuse reflectance UV-Vis. absorption spectra, with emphasis on the effect of carbon as a doping compound to the titania. Based on EPR data, the photocatalytic activity by visible light can be ascribed to the trapping of electrons at interior sites of the carbon-doped titania between the valence and conduction bands in the titania band structure, and is able to activated by visible light of a wavelength of up to 550 nm. The photocatalytic activity of the carbon-doped TiO₂ nanoparticles was evaluated by examining the decomposition of phenol by irradiation with artificial solar light (>420 nm) and the results were compared with those using Degussa P25, a commercially available titania nanomaterial.     

Efficient gas phase photodecomposition of acetone by Ru-doped Titania

Nanocrystalline titania particles doped with ruthenium oxide have been prepared by homogenous hydrolysis of TiOSO₄ in aqueous solutions in the presence of urea. The synthesized particles were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and surface area (BET) and porosity determination (BJH). The photocatalytic activity of Ru-doped titania samples was determined in the gas phase by decomposition of acetone during irradiation at 365 nm and 400 nm. The Ru-doped titania samples demonstrated enhanced photocatalytic activity under visible light. Ruthenium oxide causes the anatase to rutile transformation to occur at lower temperatures and decreasing of band-gap energy of Ru-doped samples.     

TiO2掺杂粉体的溶胶-凝胶和水热合成及其光降解甲醛

为了研究不同掺杂对二氧化钛光化学活性的影响,采用溶胶-凝胶,水热法,由TiOCl2成功制备了掺杂氮原子的二氧化钛样品,并制备了掺杂0.5%(摩尔分数)Fe3 ,Gu2 ,V5 ,Pd2 等金属离子的可见光响应型介孔材料.样品经由X射线衍射,透射电镜,Brunauer-Emmett-Teller(BET)比表面积,Barrett-Joyner-Halenda孔径分布,紫外可见光谱,光电子能谱和荧光光谱等表征;以荧光灯为光源(入射光波长λ≥410 nm),光催化降解甲醛为模式,评价了样品的催化活性.结果表明:掺杂Fe3 ,Cu2 ,V5 ,Pd2 的二氧化钛和单一掺氮的二氧化钛样品的粒径均为10 nm左右,BET比表面积为130 m2/g左右,均为锐钛矿相二氧化钛;Fe/TiO2,Cu/TiO2,V/TiO2,Pd/TiO2和TiO2/N样品的带隙能依次为:2.99,2.93,2.36,2.92 eV和2.87 eV,其在可见光下的光催化降解速率常数分别为:0.006 3,0.008 6,0.004 9,0.003 l/min和0.003 3/min.Cu/TiO2较高的荧光强度和较大的比表面积,导致了其较高的可见光光解活性.     

Enhancing Photocatalytic Activity of Polymorphic Titania Nanoparticles by NMP Solvent-based Ambient Condition Process

Solvent-based ambient condition sol (SACS) process with N-methylpyrrolidone (NMP) as the solvent, is a post-treatment technique utilized to modify polymorphic titania nanoparticles prepared by a water-based ambient condition sol process. All samples were characterized by X-ray diffraction, N₂ physisorption, CHNS analysis, UV–vis absorption spectrophotometry, FT-IR, and TEM and compared to a commercial reference titania product, Degussa P25. Photocatalytic activity, evaluated by the degradation of methyl orange under ultraviolet (UV) and visible light (VL), showed that SACS, with NMP as the solvent, is a powerful treatment to enhance TiO₂ photocatalytic activity by minimizing lattice hydroxyls and doping titania samples with nitrogen.     

Efficient visible light magnetic modified iron oxide photocatalysts

Magnetite iron oxide (Fe₃O₄) nanoparticles were synthesized via simple co-precipitation method using ferrous and ferric ions salts. Fe₃O₄ nanoparticles were modified by silica and titania. Pure and modified nanoparticles were employed for dye degradation under visible light. X-ray diffraction analysis indicated inverse spinel structure of Fe₃O₄ nanoparticles. The particle size of magnetite nanoparticles is decreased due to coating of silica and titania. Scanning and transmission electron microscopy indicated the spherical morphology for all samples. The synthesized Fe₃O₄ nanoparticles were ferromagnetic in nature with highest saturation magnetization value of 1.1034 emu as compared to silica and titania coated samples. Fourier transform infra-red spectra confirmed the incorporation of magnetite nanoparticles with silica and titania. Titania modified magnetite sample showed the highest photocatalytic activity as compared to silica modified magnetite nanoparticles and bare iron oxide under visible light irradiations.