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1.
赵延亮  王志义 《材料导报》2011,25(16):79-81,107
TiO2纳米阵列(纳米管、纳米棒)结构具有良好的力学性能、化学稳定性以及抗腐蚀性能,在许多技术领域具有广阔的应用前景。采用阳极氧化法在工业纯钛片表面制备出高度有序的TiO2纳米管阵列和纳米棒阵列,研究了电解液浓度和阳极氧化时间对TiO2纳米阵列结构的影响,并对其形成机理进行了初步探讨。结果表明,低浓度的HF酸电解液有利于制备纳米管阵列,高浓度的HF酸电解液有利于制备纳米棒阵列。  相似文献   

2.
以0.5%(质量分数)NH4F/HF/乙二醇为电解液,采用恒压二次阳极氧化法制备出高度有序的可剥离TiO2纳米管阵列,并对其晶型、形貌以及光催化性能等方面进行了研究。通过XRD测试,可知样品经500和800℃退火,分别得到锐钛矿和金红石型TiO2纳米管;通过SEM表征,可知所制备的TiO2纳米管管径约为100nm,管长约为25μm。在紫外光照射下,以TiO2纳米管阵列为催化剂,对其光催化降解酸性橙7(AO7)和Cr(Ⅵ)混合水溶液进行了研究。考察了不同晶型、pH值、不同酸性橙7和Cr(Ⅵ)初始浓度对光催化性能的影响。结果表明锐钛矿型样品光催化性能高于金红石型,三元体系TiO2/AO7/Cr(Ⅵ)中,协同效应显著,酸性条件下尤其有利于TiO2纳米管阵列光催化共去除AO7和Cr(Ⅵ)。  相似文献   

3.
采用阳极氧化法以HF水溶液为电解液制备二氧化钛(TiO2)纳米管阵列,用场致发射扫描电子显微镜和X射线光电子能谱对纳米管阵列的表面形貌、断面结构及元素组成进行表征,并使用场发射测试系统测试其场发射性能,研究了HF水溶液的pH值对TiO2纳米管阵列形貌(管径及管长)的影响。结果表明:调节电解液的pH值可改变TiO2纳米管阵列的形貌,从而提高其场发射性能。当电解液pH值为2.0时TiO2纳米管阵列的场发射开启场强降为2.52 V/μm,且具有较好的电流稳定性。  相似文献   

4.
采用阳极氧化法制备小管径(20~300 nm)的TiO2纳米管已经有很多报道,但大管径的TiO2纳米管的制备还是一个挑战。为制备大管径的TiO2纳米管,研究了高水含量的电解液对纳米管管径的影响。结果表明,纳米管的管径随水含量的增加而增加(8%~12%(体积分数)),而水含量增加到13%(体积分数)时,无法得到规则的纳米管,进一步增加水含量到20%(体积分数),只能得到致密的TiO2薄膜。此外,在含有0.3%(质量分数)NH4F和12%(体积分数)H2O的乙二醇电解液中,研究了不同氧化电压对纳米管管径的影响。结果表明,在170 V氧化电压下制备的TiO2纳米管的管径可达到600 nm。纳米管的光解水性能测试结果表明,管径的增大有利于提高TiO2纳米管的光解水性能。  相似文献   

5.
采用阳极氧化法制备出TiO_2纳米管阵列,对比了3种电解液体系[(a)氢氟酸+硫酸+水、(b)氟化钠+甘油+水、(c)氟化铵+乙二醇]对纳米管阵列形貌及光催化性能的影响。结果表明:3种电解液体系中制备出了不同长径比的TiO_2纳米管阵列,样品经450℃热处理后,主要为锐钛矿相TiO_2,同时具有良好的紫外光吸收能力,并在可见光范围内产生不同程度的波动。其中电解液(b)制备出的纳米管因具有合适的长径比而表现出优异的光催化降解气相苯的性能。  相似文献   

6.
采用阳极氧化法,在醇(丙三醇、乙二醇)-水-NH4F电解液体系中制备高度有序的TiO2纳米管阵列。采用场发射扫描电子显微镜(SEM)、X射线衍射仪(XRD)对TiO2纳米管阵列的形貌和晶型结构进行表征,讨论了阳极氧化法制备工艺(阳极氧化电压、氧化时间、电解液)对TiO2纳米管的形貌、结构及其甲基橙光催化降解性能的影响;分析了退火温度对TiO2阵列的物相及其光催化性能的影响。研究结果表明,采用高电压、增加氧化时间有利于TiO2纳米管阵列光催化的提高,在其它参数相同的情况下,采用丙三醇作为电解液制备获得的TiO2纳米管阵列较乙二醇体系具有更加优异的光催化性能。  相似文献   

7.
沈成  杨洁  沈玲  马忠权 《功能材料》2011,42(4):628-631
采用阳极氧化法在Ti片上制备高度取向的TiO2纳米管阵列.室温下,电压60V,在含有0.5%(质量分数)NH4F,1%(体积分数)HF,2%(体积分数)H2O的乙二醇电解液中,通过改变阳极氧化时间(8~20h),反应制得管长约为6.7~19.5μm,管径约为90~110nm,管壁约为20nm的TiO2纳米管阵列.利用S...  相似文献   

8.
载Pt-TiO2纳米管阵列制备及其光电催化性能   总被引:1,自引:0,他引:1  
采用阳极氧化法在纯钛箔表面制备TiO2纳米管,再用直流电沉积法在纳米管内沉积Pt,制备出载Pt-TiO2纳米管电极.并采用场发射扫描电子显微镜(FESEM)、X射线衍射(XRD)对其进行表征.研究载Pt-TiO2纳米管阵列与TiO2纳米管阵列对有机磷农药敌敌畏(DDVP)的光电催化降解效果,并与光催化、电降解做了简单对比.结果表明:所制Pt-TiO2纳米管存在锐钛矿晶型TiO2,其饱合光电流比TiO2纳米管大.与单独光催化、电降解相比,载Pt-TiO2纳米管电极光电催化降解效果更显著.  相似文献   

9.
主要介绍水热法制备TiO2纳米管/碳纳米管(TiO2/CNT)复合材料及其光催化降解染料废水的研究。结果表明,用水热法制备出的TiO2纳米管和CNT的掺杂比例为5∶1时,TiO2纳米管/碳纳米管(TiO2/CNT)复合材料光催化降解玫瑰红染料废水的效果最佳,而且TiO2纳米管/碳纳米管复合材料具有较好的稳定性。研究证实了TiO2纳米管/碳纳米管复合材料对玫瑰红染料废水在模拟太阳光照射下具有较好的光催化效果。  相似文献   

10.
碳掺杂TiO2纳米管列阵的制备及其光催化性能的研究   总被引:1,自引:0,他引:1  
采用电化学阳极氧化法制备TiO2纳米管列阵,并在CO气氛中对TiO2纳米管样品进行焙烧.XPS研究表明,在CO中焙烧的样品产生了Ti-C峰,说明有C的掺杂.SEM及XRD衍射实验表明,随着焙烧温度的升高,C的掺杂加速了TiO2纳米管的晶型结构向金红石相的转变,管壁明显增厚.以亚甲基蓝为光催化实验降解对象,研究了C掺杂对TiO2纳米管的光催化性能的影响,发现在550℃下焙烧后的TiO2纳米管具有较好的光催化活性,C的掺杂能明显提高TiO2纳米管的光催化性能.  相似文献   

11.
阳极氧化技术在氟基电解液中,对高有序氧化钛纳米管束的制备、特性及在太阳能方面的应用进行了简要综述。材料的结构证明,该材料在光分解水、光催化、气敏检测、光电转化等方面具有潜在巨大的应用。通过改变电压、电解液浓度、pH值、温度,可获得不同长度、直径、形状、壁厚的氧化钛纳米管束。在电解液中加入有机溶剂、淬火等方式掺杂,可改变氧化钛的禁带宽度,从而有效利用太阳能。  相似文献   

12.
Highly ordered titania nanotube arrays are fabricated via anodization process in electrolytes containing HF and acetic acid. Graphite was used as cathode. The size of titania can be controlled by changing anodizing voltage and bath temperature. From FE-SEM images, we observed the microstructure of titania nanotubes. Whereas, these nanotubes were amorphous; to induce crystallinity, the products were annealed at different temperatures. XRD analysis shows that the anatase and rutile phase emerge at different conditions. The optical properties were characterized via UV–vis absorption analysis. On the basis of these work, a discussion on the growth mechanism of nanotube structure was presented in this paper.  相似文献   

13.
采用电子束蒸发方法在透明导电玻璃FTO上沉积Ti金属薄膜,室温条件下在C2H6O2+NH4F中通过恒压阳极氧化法制备出超长TiO2纳米管阵列/FTO电极,并通过场发射扫描电子显微镜(FESEM),透射电子显微镜(TEM),X光电子能谱(XPS),X射线衍射(XRD)及光谱分析等方法对纳米管阵列/FTO电极进行了表征.研究表明,制备出的TiO2纳米管阵列内径43nm,管长5.4μm,经退火处理后得到长度为5μm锐钛矿相TiO2纳米管阵列/FTO透明电极,在可见光波长段的透射率为45%,在400nm波长处有一明显吸收峰.  相似文献   

14.
在不同电解液组分中采用阳极氧化法制备了不同结构参数的TiO2纳米管,考察了不同电解液组分对TiO2纳米管形貌和尺寸参数的影响.采用场发射扫描电子显微镜(SEM)和X射线衍射仪(XRD)对纳米管的形貌和结构进行了表征,并分析了电解液组分对纳米管生长的影响机制.结果表明,降低电解液中H+浓度以及减少电解液中H2O的含量可有效提高纳米管的长度.  相似文献   

15.
Self-organized and highly ordered titania nanotube arrays (TNAs) were prepared through electrochemical anodic oxidization on a titanium foil in 0.5 wt.% hydrofluoric acid (HF) electrolyte. The current density and morphology images during the formation process of TNAs were studied. Results show that the formation of TNAs includes the following processes. Initially, dense oxide of titania was rapidly formed on the titanium surface, followed by small pore formation. The adjacent small pores were then integrated and become larger pores. At the same time, small tubes were transformed. These small tubes were further integrated into larger tubes until the primary tube formation. Finally, the tubular structure was gradually optimized and eventually developed into the highly ordered TNAs. A model was proposed to explain the formation mechanism of TNAs fabricated on a titanium foil in HF acid electrolyte.  相似文献   

16.
The N-doped TiO2 nanotube array films were fabricated directly by one-step electrochemical anodic oxidation of Ti foils in an HF electrolyte containing ammonium and nitrate ions. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDX), and ultraviolet–visible (UV–vis) absorption spectroscopy, respectively. The photocatalytic activities were evaluated by the degradation of methyl orange (MO) under visible light irradiation. The results showed that N dopant was successfully introduced into the TiO2 nanotube array films. The N-doped TiO2 nanotube array films showed a red shift and an enhancement of the absorption in the visible light region compared to the undoped sample. The photocatalytic activities of the N-doped TiO2 samples were much higher than those of the undoped sample. A maximum enhancement of photocatalytic activity was achieved for the N-doped TiO2 sample prepared in 0.07 M HF electrolyte containing 1.0 M NH4NO3, and 81% of MO was degraded in 150 min under visible light irradiation.  相似文献   

17.
Although titania is one of the most important metal oxide photocatalysts, its practical applications are to some extent limited by its relatively wide band gap. Doping TiO2 by metallic species has been expressed as a promising solution to decrease its band gap energy and enhance its photocatalytic performance. In this research, we employed micro arc oxidation technique to grow Ag-doped TiO2 porous layers where influence of the electrolyte composition and the applied voltage on the surface morphology, topography, phase structure, chemical composition, and optical properties was investigated for the first time. The photocatalytic efficiency of the layers was studied using different model materials namely methylene blue and 4-chlorophenol solutions as well as gaseous benzene. A porous morphology with a rough surface was revealed by the SEM and AFM techniques. The pore size varied depending on the voltage and the electrolyte concentration. Compositional studies, conducted by XRD and XPS methods, showed that the fabricated layers mainly consisted of anatase phases. A small amount of rutile phase was also detected at high voltages, i.e. 500 V. Considering the XRD patterns, the anatase average crystalline size was determined as 67.8 and 21.5 nm for the pure TiO2 and silver doped TiO2 layers, respectively. A red-shift was observed in the absorbance edge of the layers when Ag was introduced into the titania lattice giving rise to a visible-light response. Comparing photocatalytic reaction rate constants of pure and Ag-doped titania, the doped layers exhibited more favorable potential to decompose the pollutants in aqueous phase under ultraviolet and visible lights. Moreover, the doped layers were useful to decompose the pollutants in gaseous phase under ultraviolet light.  相似文献   

18.
Do QH  Zeng C  Zhang C  Wang B  Zheng J 《Nanotechnology》2011,22(36):365402
Composite electrodes were fabricated for supercapacitor applications by depositing vanadium oxide onto multi-walled carbon nanotube (MWCNT) buckypaper using supercritical fluid deposition (SFD). The deposited thin vanadium oxide layer showed amorphous structure with excellent uniformity. In aqueous KCl electrolyte, the vanadium oxide exhibited a constant pseudo-capacitance of ~ 1024 F g(-1), which was independent of the oxide material loading (up to 6.92 wt%) and voltage scan rate (up to 100 mV s(-1)). The highest specific electrode capacitance achieved was ~ 85 F g(-1), which was almost four times that of the pristine buckypaper electrode.  相似文献   

19.
The effect of electrolyte pH and annealing temperature on the formation of TiO2 nanotube arrays in connection with the photoelectrochemical response was investigated in this article. Well-aligned TiO2 nanotube arrays were fabricated by anodisation of Ti foil in an electrolyte consisting of 1?M of glycerol (85?wt% of glycerol and 15?wt% of water) with 0.5?wt% of NH4F at 30?V for 30?min. The pH of the electrolyte was varied from pH 1 to 7. With the increase of electrolyte pH to neutral condition, the length of the nanotube arrays was increased from ~320 to 1100?nm. As-anodised TiO2 nanotube arrays were amorphous in nature. However, anatase phase was observed after annealing at 400°C and polycrystalline anatase and rutile phase could be observed by heating up to 500°C in air atmosphere. Based on the results obtained, the length and crystalline phases of TiO2 nanotube arrays affect the performance of photoelectrochemical response and photoconversion efficiency significantly.  相似文献   

20.
In the present work, tuning effects of dimethyl sulphoxide (DMSO) on the length, wall thickness, dimension and morphology of titania nanotube arrays fabricated by anodization was investigated. DMSO presented in both ethylene glycol and glycerol electrolytes provided excellent tunability in length, wall thickness and diameter of the produced TiO2 nanotube arrays by systematically varying the DMSO concentration. At the DMSO concentration of 12 wt% in ethylene glycol, the nanotube length could be up to 13.0 microm at 20 V for 8 h anodization. The TiO2 nanotube arrays produced in DMSO containing ethylene glycol or glycerol electrolytes displayed a high sensitivity to hydrogen at room temperature compared to the absence of DMSO. The further enhancement of resistance response could be achieved by coating a Pt and Pd layer on the surface of TiO2 nanotube-arrays. The presented work provided a simple way to control formation of TiO2 nanotube arrays through the tuning effects of DMSO in ethylene glycol or glycerol electrolytes.  相似文献   

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