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1.
0引言导电聚合物/无机物纳米复合材料具有纳米材料和导电聚合物的共同特性,因此在电催化、二次充电电池材料、超级电容器材料等方面具有良好的应用前景[1]。聚噻吩(PTh)以及取代聚噻吩是导电聚合物领域中较早发现的具有环境稳定性和可加工性的材料之一。近年来,有关聚噻吩/无机物纳米复合材料的制备及其光电性能的研究倍受关注,Gebeyehu等[2]用PTh敏化纳米晶TiO2光伏电池,发现其光伏效率明显优于固态光伏电池;Jayant等[3]研究了PTh中的羧基基团的影响以及在纳米晶TiO2  相似文献   

2.
以纳米管钛酸为前驱体,以NH4HCO3为N源,先机械研磨使二者混合均匀,再在Ar保护下,于不同温度焙烧4h制得N掺杂TiO2 (N-TiO2),并采用X射线粉末衍射、X射线光电子能谱、紫外-可见吸收光谱、透射电镜及N2吸附-脱附对样品进行了表征.结果显示,N以间隙掺杂方式进入TiO2晶格内.在热处理过程中,生成中间体(...  相似文献   

3.
水基溶胶-凝胶法制备稀土/碱土金属硅酸盐纳米粉   总被引:3,自引:0,他引:3  
采用水基溶胶凝胶法,以廉价的无机盐Y2O3,MgO为前驱物,Si(OC2H5)4为络合剂,PEG4000为复合表面活性剂,氨水调节pH值,并利用无水乙醇超声分散技术,成功制备了分散性良好的稀土碱土金属复合硅酸盐纳米粉xY2O3·yMgO·zSiO2(YMS),考察了初始溶液的pH值、温度及浓度对溶液—溶胶—凝胶转变的影响,并利用TG DTA,XRD,TEM分析手段对复合硅酸盐纳米粉YMS的性质进行了研究。实验表明,在60℃相似文献   

4.
低热固相法制备纳米MnO2/CNT超电容复合电极的循环稳定性   总被引:1,自引:0,他引:1  
为了改善纳米MnO2超级电容器电极的充放电循环稳定性,以Mn(OAc)2·4H2O、NH4HCO3和碳纳米管(CNT)为原料,采用低热固相反应得到前驱体,再经焙烧和酸处理,制备了一系列CNT含量不同的纳米MnO2/CNT复合电极材料,并用X射线衍射(XRD)、透射电镜(TEM)和Brunauer-Emmett-Teller(BET)比表面积测定方法对其进行了表征.XRD分析结果表明,复合材料中的MnO2为纳米γ-MnO2.研究了复合电极在1 mol·L-1 LiOH电解质中的电化学性能,并与不含CNT的纯纳米MnO2电极进行了比较.结果表明,含CNTs为10%(w,质最分数,下同)和20%的MnO2/CNT复合电极的循环稳定性远优于纯纳米MnO2电极的循环稳定性,其中含10%CNTs的MnO2/CNT复合电极不仪具有良好的循环稳定性,而且在1000 mA·g-1高倍率充放电条件下仍具有200 F·g-1的高比电容.  相似文献   

5.
To improve the charge/discharge cycle stability of a nanostructured manganese dioxide electrode for supercapacitor applications, a series of nano-MnO2/carbon nanotube (CNT) hybrid electrode materials with different mass fractions of CNTs were prepared. The materials were prepared using a room-temperature solid-grinding reaction betweenMn(OAc)2·4H2Oand NH4HCO3 in the presence of CNTs to obtain a precursor. This was followed by calcination and an acid-treatment process and the products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) surface analysis. XRD results indicated that the MnO2 in the composites was nanostructured 酌-MnO2. Electrochemical performance of the MnO2/CNT composite electrodes in 1 mol·L-1 LiOH alkaline aqueous electrolyte was studied and compared to a pure nano-MnO2 electrode without CNTs. The MnO2/CNT composite electrodes with 10% or 20% (w, mass fraction) CNTs showed far superior cycle stability than the pure MnO2 electrode. The MnO2/CNT composite electrode with 10% CNTs exhibited good cycling stability and also a high specific capacitance of 200 F·g-1 at a high charge/discharge current rate of 1000 mA·g-1.  相似文献   

6.
利用水引发固相反应方法合成氮化铝纳米粉   总被引:1,自引:1,他引:0  
李凯  刘振刚  于美燕  董守义  王琪珑  郝霄鹏  崔得良 《化学学报》2004,62(12):1144-1147,MJ04
以AlCl3和Li3N为前驱物,利用过量Li3N与水反应大量放热现象,引发两种前驱物之间的固相反应合成了AlN纳米粉.X射线衍射分析、红外吸收光谱、透射电子显微镜以及X射线光电子能谱测试结果表明,利用这种新的合成方法制备的氮化铝主要是六方相,而且颗粒细小.另外,这种方法反应迅速、操作过程简便,有利于降低制备成本和扩大制备规模.  相似文献   

7.
采用固相浸渍法制备了一系列NiO/CeO2催化剂,并通过与常规湿浸渍法比较,考察了制备方法对催化剂和CO氧化反应性能的影响.同时结合X射线衍射(XRD),N2吸附-脱附(BET),透射电镜(TEM),氢气-程序升温还原(H2-TPR),拉曼(Raman)光谱,X射线光电子能谱(XPS)等手段对催化剂的结构和表面物种分散状态进行了表征.CO氧化活性测试结果表明,当镍负载量相同时,固相浸渍法制备的催化剂相比于湿浸渍法表现出更好的催化性能.TEM、XPS、H2-TPR结果表明,固相浸渍法更有利于加强镍铈间的相互作用和得到高分散的镍物种,从而促进镍物种的还原.Raman结果表明固相浸渍法相比于湿浸渍法能产生更多氧空位,这有利于氧气在催化剂表面的活化,使得CO氧化反应更容易进行.  相似文献   

8.
微波固相法快速制备氮掺杂石墨烯   总被引:1,自引:0,他引:1  
以鳞片石墨为原料,首先通过Hummers法制备氧化石墨,再将洗涤至中性的氧化石墨分散液与乙二胺反应得到功能化石墨烯。干燥后的功能化石墨烯在微波辐照下能瞬间产生高热,促使接枝的乙二胺分子分解并实现对石墨烯原位掺杂制备出氮掺杂石墨烯。利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、X射线衍射(XRD)、X射线能谱(EDS)对样品的形貌、结构和组成进行了表征。结果表明:该合成途径能成功实现对氧化石墨烯的还原和掺杂,所合成的氮掺杂石墨烯呈现透明绢丝状结构。  相似文献   

9.
以鳞片石墨为原料, 首先通过Hummers法制备氧化石墨, 再将洗涤至中性的氧化石墨分散液与乙二胺反应得到功能化石墨烯。干燥后的功能化石墨烯在微波辐照下能瞬间产生高热, 促使接枝的乙二胺分子分解并实现对石墨烯原位掺杂制备出氮掺杂石墨烯。利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、X射线衍射(XRD)、X射线能谱(EDS)对样品的形貌、结构和组成进行了表征。结果表明:该合成途径能成功实现对氧化石墨烯的还原和掺杂, 所合成的氮掺杂石墨烯呈现透明绢丝状结构。  相似文献   

10.
孙敬方  张雷  葛成艳  汤常金  董林 《催化学报》2014,35(8):1347-1358
采用固相浸渍法和常规湿浸渍法制备了一系列CuO/CeO2催化剂,并结合X射线衍射(XRD)、氢气-程序升温还原(H2-TPR)、激光拉曼光谱(LRS)、原位漫反射红外光谱(in situ DRIFTS)、X射线光电子能谱(XPS)等手段考察了制备方法对催化剂结构性质及其在CO氧化反应中性能的影响. XPS和H2-TPR结果表明,固相浸渍法更有利于得到高分散的铜物种,并促进CuO物种的还原. LRS结果表明,相比于湿浸渍法,固相浸渍法能产生更多氧空位,而这些氧空位可以活化参与反应的O2. CO氧化活性测试结果表明,当铜负载量相同时,固相浸渍法制备的催化剂相比于湿浸渍法表现出更好的催化性能. 结合多种表征结果发现,催化剂CO氧化性能与其表面氧空位和Cu+-CO浓度紧密相关,提出了CuO/CeO2催化剂在CO氧化反应中可能的协同作用机制.  相似文献   

11.
In this paper,a thiol-functionalized nanophotocatalyst MPTES/TiO_2 was first synthesized by one-pot method using P123 as a template.X-ray diffraction confirms the complete anatase crystalline of thiol-functionalized TiO_2,N_2 adsorption-desorption isotherm demonstrated that these materials possess high surface area and mesoporous structure.The results of XPS show that MPTES has been successfully polymerized in mesoporous structured TiO_2.The photodegradation of phenanthrene(PHE) was investigated under vi...  相似文献   

12.
光催化法是近年来发展较快的一种环境治理技术,掺杂型TiO_2催化剂是当前研究的焦点之一.以四氯化钛为主要原料,利用简单的溶胶法制备了纳米TiO_2、Fe/TiO_2粉体,研究发现掺杂铁,能够有效地延缓锐钛矿型TiO_2向金红石型TiO_2的转变,提高Fe/TiO_2粉体的光催化活性,并且500℃焙烧后的Fe/TiO_2催化剂,在紫外光下催化活性较好.  相似文献   

13.
利用离子交换法将AgBr负载到水热合成的麦羟硅钠石(magadiite,MD)载体上,通过光照还原生成新型Ag-AgBr/MD复合光催化剂;采用X射线衍射仪、扫描电镜、透射电镜分析了复合催化剂的结构,采用紫外-可见分光光度计评价了AgBr负载量和pH对复合催化剂可见光催化降解罗丹明(RhB)水溶液活性的影响.结果表明,随着AgBr负载量的增加,RhB的降解率先增大后减小,随pH的增大RhB的降解率减小.当n(AgNO3)∶n(MD)=2∶1,pH=9时,复合光催化剂具有较强的光吸收性能,且AgBr高度分散在载体MD表面,因而对RhB的光催化降解性能最高.  相似文献   

14.
A novel chlorine-doped titanium dioxide catalyst with visible light response was prepared by hydrolysis of tetrabutyl titanate in hydrochloric acid. The catalyst samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS). Results showed that the doped element of Cl lowered the temperatures of phase transformation of TiO2 from amorphous to anatase and from anatase to rutile. The absorption edge of chlorine-doped TiO2 calcined at 300°C shifted to visible light region. X-ray photoelectron spectroscopy results proved that chlorine existed in the TiO2 crystal lattice as anion. The photocatalytic degradation of phenol showed that under visible light (λ > 400 nm) irradiation, the chlorine-doped TiO2 calcined at 300°C displayed the best performance, the degradation ratio of phenol was 42.5% after 120 min. Translated from Chinese Journal of Catalysis, 2006, 27(10): 890–894 [译自: 催化学报]  相似文献   

15.
CdS nanoparticles were prepared by the precipitation method. Pt was loaded on CdS by photodeposition. SiO2-Pt-CdS was synthesized via hydrolysis of tetraethylorthosilicate in the presence of Pt-CdS. The samples were characterized by XRD, BET, PL and UV-Vis techniques. The photocatalytic activity of the samples for hydrogen evolution was investigated under visible light irradiation (λ ≥ 420 nm). The stability and activity of CdS was improved by coating SiO2.  相似文献   

16.
SiC-BiVO4-P and SiC-BiVO4-H composites have been prepared by precipitation method and hydrothermal method, respectively. Rod-like BiVO4 particles dispersed on the surface of micro-sized SiC particles homogeneously in SiC-BiVO4-H. Due to the formed heterostructure between BiVO4 and SiC, photo-generated electrons and holes were effectively separated. Under visible light irradiation, SiC-BiVO4-H exhibited the best performance for photocatalytic oxidation of Rhodamine B, achieved about 7.5 times improvement in photocatalytic degradation rate constants compared with that of the pristine SiC powder. The possible photocatalysis mechanism of SiC/BiVO4 related to the band positions of the semiconductors under visible light irradiation was also discussed in detail. In addition, the radicals trapping experiments revealed that all three radicals (holes, OH, and O2?) play an important role in the Rhodamine B degradation.  相似文献   

17.
采用动力学方法研究了MnO2颗粒物对TiO2光催化降解苯胺活性的影响,对比考察了光催化降解过程中苯胺溶液的UV吸收光谱的变化,并用HPLC方法鉴别了中间产物.结果表明,少量MnO2颗粒物就能使TiO2光催化降解苯胺的活性受到明显的抑制,不同结构的二氧化锰致毒效应由大到小的顺序为:δ-MnO2α-MnO2β-MnO2;降解不同时间后溶液的UV吸收光谱的变化也反映了MnO2颗粒物具有同样的致毒效应;MnO2颗粒物不改变TiO2光催化降解苯胺的途径,但对生成中间产物的基元步骤的抑制程度不同。  相似文献   

18.
<正>Nitrogen-doped TiO_2 nanophotocatalysts were prepared,and characterized by XRD patterns and UV-vis spectroscopy.The results indicated that nitrogen was doped effectively and the shift of the absorption edge to a lower energy and a stronger absorption in the visible light region were observed.The calcinations temperature is a key factor to narrow the band gap of titania,and consequently affects the response to visible light of nitrogen-doped TiO_2 nanocrystals.This photocatalyst can effectively inhibit the growth of Helminthosporium maydis,whereas undoped TiO_2 nanocrystals cannot inhibit the growth of H.maydis under the same experimental conditions.  相似文献   

19.
Uniform flower-like TiO_2 coated Au nanostars and core-shell Au@Ag natiostars with different amounts of Ag coating were prepared through a facile method by hydrolysis of TiF_4 under an acidic environment.The photocatalytic capability of these flower-like nanocomposites under visible light irradiation was found to be enhanced by up to 4.7-fold compared to commercial P25 TiO_2 nanoparticles.The enhanced photocatalytic activity was ascribed to improved light absorption and hot electron injection from the photo-excited Au@Ag core to the TiO_2 shell.  相似文献   

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