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铁氮共掺杂TiO2光催化剂的制备及光催化性能 总被引:2,自引:1,他引:1
采用溶胶-凝胶法与微波合成法相结合制备铁氮共掺杂的TiO2光催化剂。通过XRD、FT-IR、UV-Vis、PL等对Fe-N-TiO2样品进行表征和分析,并以亚甲基蓝(MB)作为目标降解物,考察经不同温度热处理及不同掺铁量的样品对MB的降解效果。结果表明所制备的样品在700℃热处理5h后为锐钛矿相与金红石相混晶,样品的吸收阈值波长向可见光红移约45nm。铁氮共掺杂抑制了样品从锐钛矿相向金红石相的转变,提高了TiO2的光催化活性。在普通日光灯下,热处理温度为600℃、掺铁量与TiO2摩尔比为1︰200条件下制备的样品,其光催化活性明显高于Degussa P25。 相似文献
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采用溶胶-凝胶法制备了纯TiO2,1%Sm3+或2%Gd3+单掺杂和1%Sm3+/2%Gd3+共掺杂TiO2复合粉体,采用XRD和SEM/EDAX等技术进行表征。以对亚甲基蓝的光催化降解为目标反应,评价了TiO2复合粉体的光催化活性,探讨了Sm3+/Gd3+共掺杂、亚甲基蓝初始浓度和粉体投加量对TiO2粉体光催化活性的影响机制。结果表明,Sm3+/Gd3+共掺杂可以显著提高TiO2粉体的光催化活性;Sm3+/Gd3+共掺杂在TiO2粉体中产生协同作用,抑制了TiO2由锐钛矿相向金红石相转变,使TiO2粒径尺寸减小,增大了TiO2的晶格畸变。当亚甲基蓝初始浓度为4mg/L和粉体投加量为2g/L时,TiO2复合粉体的光催化活性最高,对亚甲基蓝光催化降解率达99.71%;降解亚甲基蓝反应符合Langmuir-Hinshelwood动力学方程。 相似文献
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采用溶胶-凝胶法制备铁掺杂纳米TiO2光催化剂。通过XRD、FT-IR、UV-Vis、PL等对Fe-TiO2样品进行表征和分析,并以亚甲基蓝(MB)作为目标降解物,考察经不同热处理温度及不同掺铁量Fe-TiO2样品对MB的降解效果。结果表明所制备的Fe-TiO2样品的晶型为锐钛矿相与金红石相的混晶相,铁掺杂抑制了晶粒的生长和晶型的转变,样品的吸收阈值波长向可见光红移约68nm,提高了TiO2的光催化活性。在普通日光灯下,经500℃热处理、掺铁量与TiO2摩尔比为1∶200条件下制备的催化剂其光催化活性明显高于Degussa P25。 相似文献
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通过溶胶-凝胶法制备铁铕共掺杂的TiO_2(Fe~(3+)-Eu~(3+)/TiO_2)空心微球,采用XRD、TEM、BET和XPS等对样品进行表征,以亚甲基蓝(MB)的光催化降解为目标反应,评价其光催化活性。结果表明:SiO_2微球表面均匀地包覆了1层TiO_2,超声有利于提高SiO_2@TiO_2复合微球间的分散性,同时也发现煅烧前对SiO_2@TiO_2复合微球进行研磨处理后所得的Fe~(3+)-Eu~(3+)/TiO_2空心微球部分塌陷,而未研磨和煅烧后研磨所得Fe~(3+)-Eu~(3+)/TiO_2空心微球完整性较好。XRD和BET分析表明,Fe~(3+)-Eu~(3+)/TiO_2空心微球为锐钛矿且具有良好的介孔结构,铁铕共掺杂在TiO_2空心微球中产生协同作用,使Fe3+-Eu3+/TiO2空心微球的粒径进一步减小,比表面积增大。当Fe~(3+)的掺杂量为1.0%、Eu~(3+)的掺杂量为0.5%时,Fe~(3+)-Eu~(3+)/TiO_2空心微球的光催化活性最高。 相似文献
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以钛酸四丁酯(TBT)为原料, 采用溶胶-凝胶法制备了纯TiO2和La3+-Pr3+共掺杂复合粉体(La3+-Pr3+/TiO2), 采用XRD、 UV-Vis和TEM等测试手段分析了在紫外光照射下, 以降解甲基橙为探针反应研究其可见光催化性能。结果显示: 所有样品均为锐钛矿相纳米TiO2, 稀土元素镧和镨掺杂后TiO2特征衍射峰宽化, 强度降低; 与纯TiO2、 镧掺杂TiO2与镨掺杂TiO2相比, 光催化剂La3+-Pr3+共掺杂TiO2颗粒的粒径更小, 比表面积更大, 光吸收边红移程度更显著; 与未掺杂和单一掺杂的TiO2相比较, 共掺杂的TiO2具有更高的可见光催化性能。当La3+与TiO2和Pr3+与TiO2的摩尔比分别为1.0%和0.2%时, 可见光催化性能最好。可见光催化性能的提高归因于镧和镨的协同作用。 相似文献
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Chen Jie Luo Guimin Zou Xiangyu Zhang Hongbo Yuan Deshun Wang Haotian Su Chunhui 《Journal of Materials Science: Materials in Electronics》2022,33(26):20837-20845
Journal of Materials Science: Materials in Electronics - The Sm3+/Eu3+ doped transparent glass ceramics (GCs) containing Na7.15(Al7.2Si8.8O32) crystallite were successfully prepared by melt... 相似文献
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Carbon and boron co-doped TiO2 photocatalysts were prepared firstly by the gel-hydrothermal method, that is, synthesized through sol-gel process followed by hydrothermal in the glucose solution. The prepared photocatalysts were characterized by XRD, Raman spectra, TEM, N2 physical adsorption, XPS, and UV-vis absorption spectra. It was found that the co-doped TiO2 has a larger BET surface areas and a narrower band gap than undoped TiO2. The experimental results show that the coke carbon generated on the carbon doped TiO2 surface act as a photosensitizer and has the photosensitization effect under the visible light. Except for carbon sensitization effect, the boron and carbon co-doped TiO2 has synergistic effect which is responsible for effective photo-degradation of 2,4-dichlorophenol in the visible light irradiation. 相似文献
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以钛酸四正丁酯为先驱物,采用溶胶-凝胶法制备铁铝共掺杂的TiO2(Fe3+/Al3+-TiO2)复合光催化剂,并用XRD、UV-Vis等进行表征,系统研究煅烧温度、光催化体系中的盐对Fe3+/Al3+-TiO2复合光催化剂在自然光条件下光催化降解甲基橙性能的影响。结果表明,Fe3+/Al3+-TiO2光催化降解甲基橙的性能随着煅烧温度的升高而增强,催化体系中的HCO3-和NO2-使Fe3+/Al3+-TiO2复合光催化剂的催化活性有所降低。 相似文献
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Shu-Qing Yan 《Journal of Materials Science: Materials in Electronics》2014,25(4):1868-1872
BiPO4:Eu3+, BiPO4:Sm3+, and BiPO4:(Eu3+, Sm3+) powders were synthesized by a hydrothermal route. The X-ray diffraction and Fourier-transform infrared spectroscopy results show that the samples are pure hexagonal phases. The excitation spectrum of BiPO4:Eu3+ sample shows the characteristic absorption peaks of Eu3+ corresponding to the direct excitation from the ground state to the higher excited states of the europium f-electrons. The excitation spectrum of BiPO4:Sm3+ sample consists of several narrow excitation lines due to the characteristic f–f transition of Sm3+. The emission spectrum of BiPO4:Eu3+ specimen excited by 395 nm consists of lines mainly locating in the red area. The emission spectrum of BiPO4:Sm3+ sample is composed of four emission bands, which are attributed to transitions from 4G5/2 excited state to 6HJ/2 (J = 5, 7, 9, and 11) ground states of Sm3+. The excitation and emission spectra of BiPO4:(Eu3+, Sm3+) samples are different from single doped BiPO4 samples. The introduction of Sm3+ can broaden and enhance the excitation intensity of Eu3+ and improve the emission dominance of Eu3+ at 617 nm. 相似文献
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采用溶胶-凝胶法制备了Er-Ce共掺杂的TiO2纳米粉体,并以亚甲基蓝溶液为目标降解物研究了掺杂纳米TiO2粉体在紫外光作用下的光吸收和光催化性能。采用TG-DTA、XRD和TEM等测试技术对样品的晶型、形貌和粒径尺寸进行了表征。结果表明,Er-Ce共掺杂的TiO2粉体最佳热处理温度为550℃,结晶完整、主晶相为锐钛矿型,平均粒径约为20nm;掺杂可使TiO2吸收带发生红移,光催化性能增强;共掺杂体系的最佳量为n(Er):n(TiO2)=0.1%,n(Ce):n(TiO2)=0.05%。此掺杂量的TiO2粉体对亚甲基蓝有良好的降解效果,反应2h降解效果达到92.37%,优于同等条件下制备的未掺杂的纯TiO2粉体。掺杂复合光催化剂对亚甲基蓝的降解遵循一级动力学方程。 相似文献
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采用超声辅助溶胶-凝胶法,以钛酸丁酯为原料,尿素为N源,硝酸镧为La源,制备了N与La共掺杂纳米TiO_2/电气石复合材料。采用XRD、UV-Vis、SEM-EDS和XPS对复合材料的结构和性能进行了表征。以2,4,6-三硝基甲苯作为目标污染物,考察了N与La共掺杂纳米TiO_2/电气石复合材料的光催化活性及再生利用性能。结果表明:N与La共掺杂并负载电气石后,两者协同作用使TiO_2晶粒更加细化,光吸收范围向可见光区拓展,N与La共掺杂纳米TiO_2/电气石复合材料具有良好的光催化活性和再生利用性能,且在模拟可见光照射条件下对2,4,6-三硝基甲苯具有良好的去除效果。 相似文献
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《Materials Letters》2005,59(24-25):3115-3118
Titanium dioxide (TiO2) nano-fibers doped with Gd3+ were synthesized by two-step synthesis method. The formed fibers were visualized from transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results showed that the average diameter of the TiO2 nano-fibers was 60–80 nm and the length of fibers was in the range of 6–7 μm. The TiO2 nano-fibers doped with Gd3+ heat treated in glycerol solvent had smaller crystal size than those without heat treatment. However, the size of TiO2 nano-fibers decreased with increasing the heating temperature. The results obtained in the photocatalytic degradation of methyl orange indicated that the photocatalytic activity of the TiO2 nano-fibers doped with Gd3+ appeared a little reduction relative to that of TiO2 nanopowders. 相似文献
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Liang-Hai Li Juan Lu Zuo-Shan Wang Lu Yang Xiu-Feng Zhou Lu Han 《Materials Research Bulletin》2012,47(6):1508-1512
The CN co-doped TiO2 nanorods were synthesized by the vapor transport method of water molecules, and urea was used as the carbon and nitrogen source. The samples were characterized by X-ray diffraction and photoelectron spectroscopy analysis. The scanning electron microscope images showed that as-prepared TiO2 powders were nanorods, which were formed by the stacking of nanoparticles with a uniform size around 40 nm. The degradation of methylene blue with the prepared nanorods demonstrated the photocatalytic activities of TiO2 under visible light are improved by doping with C and N elements. The main reasons were discussed: doping with C and N elements could enhance the corresponding visible-light absorption of TiO2. On the other hand, doping C and N could create more oxygen vacancies in the TiO2 crystals, which could capture the photogenerated electrons more effectively. Thus, more photogenerated holes could be left to improve the photocatalytic activity of TiO2. 相似文献