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1.
微纳米碳空心球的合成研究及应用进展   总被引:1,自引:0,他引:1  
微纳米碳空心球具有密度小、比表面积大、阻尼性能高、稳定性好和可填充中空结构等特性,在锂离子电池、催化、超级电容器、储氢、超导和阻尼等领域具有广阔的应用前景。本文结合近年来国内外的最新研究进展,综述了模板法、液相法和气相法等微纳米碳空心球的合成方法,评价了各种方法的特点,并讨论了微纳米碳空心球的应用研究进展。  相似文献   

2.
石墨炔是一种新型碳材料,自2010年实验室成功制备后受到广泛关注。石墨炔是一种由spsp2杂化碳组成的高度共轭结构。随着石墨炔合成化学的发展,多种不同构型的石墨炔被制备和表征。石墨炔特殊的电子和孔结构,使其在催化领域中具有广泛的应用。本文总结了近年来石墨炔材料在表征方法和光电催化反应方面的研究进展,并探讨了石墨炔未来发展的机遇和挑战。  相似文献   

3.
氢取代石墨单炔是一种仅由苯环上的sp2杂化碳和氢与乙炔基上的sp杂化碳组成具有与石墨炔相似平面网状结构的二维富碳材料。本文以碳化钙和三溴苯为原料,通过机械化学方法合成了氢取代石墨单炔,并通过X射线电子能谱、拉曼光谱、固体核磁共振成像1H谱和透射电子显微镜加以证实。紫外可见漫反射吸收光谱和电化学测试表明样品为p型半导体,带隙为2.30 eV,在硫酸钠溶液(pH = 7)中的析氧起始过电位为0.04 V,在催化产氧和光催化方面具有应用潜力。  相似文献   

4.
采用水热法制备TiO2空心球,以TiO2空心球为载体,采用等体积浸渍法分别制备了不同V负载量(3%~10%)的V2O5/TiO2和稀土改性后的V2O5-CeO2/TiO2催化剂,利用XRD,SEM,EDS,TEM对TiO2空心球及V2O5-CeO2/TiO2催化剂进行了表征,结果表明,空心球TiO2分散性良好,粒径在1.5μm左右,且其为锐钛矿结构,负载的V和大部分的Ce均匀分散在TiO2空心球体内部或者表面而未破坏TiO2空心球结构。考察了催化剂对氯苯的催化燃烧性能,活性评价结果表明当V负载量在5%时,V2O5/TiO2催化剂对氯苯催化燃烧性能最佳,在掺杂10%的稀土Ce后,催化燃烧氯苯的活性得到明显提高。  相似文献   

5.
石墨炔是由sp和sp2两种杂化碳构成的新型二维碳同素异形体。基于石墨炔化学合成规律和独特优势,利用其他芳炔前体替代六乙炔基苯,可以获得结构特异、尺寸可控的石墨炔基衍生物,而局域碳骨架的改变可以实现石墨炔衍生物性能调控,包括电导率、带隙、迁移率、空腔尺寸和电荷分离等。这类具有优良半导体性能的石墨炔基衍生物可以广泛应用于电化学储能、电催化、光电转换器件、非线性光学等诸多领域。本文主要综述了近年来石墨炔衍生物的优化设计、结构表征和光电性能,并对其代表性应用进行了总结和展望。  相似文献   

6.
许静静  刘幸  周虎 《色谱》2016,34(12):1199-1206
蛋白质翻译后修饰(PTMs)是调节细胞内生理活动的重要途径。该文总结了近年来PTMs蛋白质组学相关的分离方法,包括反相(RP)色谱法、离子交换(IEX)色谱法、亲水相互作用色谱(HILIC)法、多孔石墨化碳(PGC)色谱法、毛细管电泳(CE)法及分子筛色谱(SEC)法等。这些新方法为磷酸化、乙酰化、糖基化等PTM肽段或蛋白质的鉴定提供了更高的分离度和灵敏度。此外,该文也介绍了蛋白质领域其他重要分离方法的研究进展,这些方法可能被进一步应用于PTMs蛋白质组学的研究中。  相似文献   

7.
钒氧化物微/纳米空心球由于具有比表面积高、负载容量大、密度低等特性,在催化剂、传感器、锂离子电池、电池阴极材料等相关行业中有着广泛的应用前景和研究价值。本文综述了钒氧化物微/纳米空心球材料的制备方法,包括软模板剂法、硬模板剂法、水热合成法和溶剂热合成法等的研究进展,并对今后的研究方向进行了展望。  相似文献   

8.
以甲壳胺(CTS)和钴、铁盐作有机前体与反应物,采用共沉淀法制备了CTS/钴铁层状双金属氢氧化物复合物.样品经过氩气氛、空气氛煅烧,生成氮掺杂部分石墨化碳/钴铁氧化物复合材料(N-PGC/CoFe-TMOs).CTS热解且被过渡金属催化生成部分石墨化碳,同时原位氮掺杂,氮/碳原子比例约为1/18.N-PGC/CoFe-TMOs具有大孔和介孔结构,用作超级电容器电极材料兼有双电层电容与赝电容特征.在2 A·g-1电流密度下,复合物比电容达到671.1 F·g-1,远大于纯钴铁氧化物比电容283.3 F·g-1,复合物具有典型的协同效应.电流密度增加到10 A·g-1时,N-PGC/CoFe-TMOs比电容为573.3 F·g-1,经过5000次充放电循环,复合物比电容保留率为66.4%.制备方法简便、通用,煅烧过程可一步制备氮掺杂的部分石墨化碳并与过渡金属氧化物复合,产物电化学性能优异.  相似文献   

9.
徐秀娟  秦金贵李振 《化学进展》2009,21(12):2559-2567
石墨烯是目前发现的唯一存在的二维自由态原子晶体,它是构筑零维富勒烯、一维碳纳米管、三维体相石墨等sp2杂化碳的基本结构单元,具有很多奇异的电子及机械性能。因而吸引了化学、材料等其它他领域科学家的高度关注。本文介绍了近几年石墨烯的研究进展,包括石墨烯的合成、去氧化、化学修饰及应用前景等方面的内容。  相似文献   

10.
钒氧化物微/纳米空心球由于具有比表面积高、负载容量大、密度低等特性,在催化剂、传感器、锂离子电池、电池阴极材料等相关行业中有着广泛的应用前景和研究价值。本文综述了钒氧化物微/纳米空心球材料的制备方法(包括软模板剂法、硬模板剂法、水热合成法和溶剂热合成法)及相关研究进展,并对今后的研究方向进行了展望。  相似文献   

11.
在高岭土负载的镍催化剂上,于850 ℃催化裂解乙炔制备了直径约500 nm 的空心碳球.用XRD、TEM、SEM和显微激光Raman光谱对所得的碳球及催化剂进行了表征,并初步探讨了反应机理.  相似文献   

12.
In this study,we have established a facile method to synthesize functional hollow carbon spheres with large hollow interior,which can act as active colloidal catalysts.The method includes the following steps:first,hollow polymer spheres with large hollow interior were prepared using sodium oleate as the hollow core generator,and 2,4-dihydroxybenzoic acid and hexamethylene tetramine(HMT) as the polymer precursors under hydrothermal conditions;Fe 3+ or Ag + cations were then introduced into the as-prepared hollow polymer spheres through the carboxyl groups;finally,the hollow polymer spheres can be pseudomorphically converted to hollow carbon spheres during pyrolysis process,meanwhile iron or silver nanoparticles can also be formed in the carbon shell simultaneously.The structures of the obtained functional hollow carbon spheres were characterized by TEM,XRD,and TG.As an example,Ag-doped hollow carbon spheres were used as colloid catalysts which showed high catalytic activity in 4-nitrophenol reduction reaction.  相似文献   

13.
采用PMMA为模板制备碳空心球材料,并以碳空心球材料为导电骨架与硫材料复合制得碳空心球/硫复合材料. SEM和TEM照片显示,硫材料能均匀地填充在碳空心球的孔道和腔体内部. 采用恒电流充放电测试碳空心球/硫复合电极的电化学性能. 结果表明,在100 mA·g-1、500 mA·g-1、1 A·g-1、2 A·g-1 和5 A·g-1电流密度下,碳空心球/硫复合电极可逆放电容量分别为1145 mAh·g-1、824 mAh·g-1、702 mAh·g-1、586 mAh·g-1和395 mAh·g-1,呈现出较优异的倍率循环寿命.  相似文献   

14.
新型氧化铝空心球的制备及表征   总被引:7,自引:1,他引:7  
以胶体碳球为模板, 廉价的硝酸铝为铝源, 成功制备出了新型的大小可控的氧化铝空心球. 通过透射电子显微镜(TEM)、扫描电子显微镜(SEM)、能量扩散X射线(EDX)、X射线粉末衍射(XRD)等手段对合成产品进行了表征, 并考察了不同合成条件对空心球形貌的影响. 实验结果表明, 合成的氧化铝空心球大小均一, 粒径及壁厚均可调节. 在该实验条件下, 硝酸铝浓度及吸附时间的改变对产品结果没有明显的影响, 而吸附温度的改变引起了产品表面光滑度及壁厚的改变.  相似文献   

15.
Microporous organic networks (MONs) have been considered as an ideal substrate to stabilize active metal nanoparticles. However, the development of highly water‐dispersible hollow MONs nanostructures which can serve as both the reducing agent and stabilizer is highly desirable but still challenging. Here we report a template‐assisted method to synthesize hollow microporous organic network (H‐MON) spheres using silica spheres as hard template and 1,3,5‐triethynylbenzene as the building blocks through a Glaser coupling reaction. The obtained water‐dispersible H‐MON spheres bearing sp‐ and sp2‐hybridized carbon atoms possess a highly conjugated electronic structure and show low reduction potential; thus, they can serve as a reducing agent and stabilizer for electroless deposition of highly dispersed Pd clusters to form a Pd/H‐MON spherical hollow nanocomposite. Benefitting from their high porosity, large surface area, and excellent solution dispersibility, the as‐prepared Pd/H‐MON hollow nanocomposite exhibits a high catalytic performance and recyclability toward the reduction of 4‐nitrophenol.  相似文献   

16.
利用胶体碳球为模板制备SiO2、TiO2、SnO2空心球   总被引:1,自引:1,他引:0  
介观尺度的氧化物空心球材料在许多领域都有着潜在的应用价值[1],因此近年来受到人们的广泛关注。其制备方法包括:模板法[2],声化学法[3],水热法[4]等。其中胶体粒子模板合成是制备氧化物空心球材料的一条最为有效的途径。常见的胶体粒子有金、银、CdS的纳米粒子,介观尺度的SiO  相似文献   

17.
CeO2 hollow microspheres have been fabricated through a simple thermal decomposition of precursor approach. The precursor with an average size of 10 μm was prepared in a reverse microemulsions containing Ce(NO3)3·6H2O and CO(NH2)2 at 160 °C. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED) and scanning electron microscopy (SEM). The possible formation mechanism of hollow spheres was discussed. In addition, the CeO2 hollow microspheres modified glassy carbon electrode exhibit excellent sensing performance towards methyl orange, which provide a new application of CeO2 hollow spheres. The catalytic activity of CeO2 hollow spheres on the thermal decomposition of ammonium perchlorate (AP) also was investigated by TGA. The catalytic performance of CeO2 hollow spheres is superior to that of commercial CeO2 powder.  相似文献   

18.
This report presents a facile approach for the low‐temperature synthesis of crystalline inorganic‐oxide composite hollow spheres by employing the bulk controlled synthesis of inorganic‐oxide nanocrystals with polymer spheres as templates. The sulfonated polystyrene gel layer can adsorb the target precursor and induce inorganic nanocrystals to grow on the template in situ. The crystalline phase and morphology of the composite shell is tunable. By simply adjusting the acidity of the titania sol, crystalline titania composite hollow spheres with tunable crystalline phases of anatase, rutile, or a mixture of both were achieved. The approach is general and has been extended to synthesize the representative perovskite oxide (barium and strontium titanate) composite hollow spheres. The traditional thermal treatment for crystallite transformation is not required, thus intact shells can be guaranteed. The combination of oxide properties such as high refractive index, high dielectric constant, and catalytic ability with the cavity of the hollow spheres is promising for applications such as opacifiers, photonic crystals, high‐κ‐gate dielectrics, and photocatalysis.  相似文献   

19.
水热沉淀法制备掺铁二氧化钛中空球及其光催化性能   总被引:1,自引:0,他引:1  
 以碳球为模板剂, 采用水热沉淀法制备了不同配比掺 Fe 的 TiO2 (Fe-TiO2) 中空球, 并运用 X 射线粉末衍射、扫描电子显微镜、元素分析能谱、红外光谱和热重等方法对其进行了表征. 结果表明, 中空球为锐钛矿相, 大小为 0.5~3.20 ?m, 壳层厚度为 30~60 nm, 比表面积为 150~300 m2/g. 随着 Fe 掺杂量的增加, 中空球在可见光区的吸收强度逐渐增加. 光催化降解实验表明, 掺 Fe 后, TiO2 中空球的可见光催化活性升高, 其中 0.5% Fe-TiO2 在 80 min 内降解亚甲基蓝超过 75%. 同时还讨论了光催化机制.  相似文献   

20.
Here we report a spontaneous combustion reaction in synthesizing Pt hollow capsules. In brief, Pt nanoparticles were loaded on the surface of colloidal carbon spheres by wet-chemical impregnation. When Pt-loaded carbon spheres were taken out of an argon-filled tube furnace at room temperature and exposed to air, they underwent spontaneous combustion. The internal carbon spheres templates were removed to leave nanostructured Pt hollow capsules. There are at least two critical conditions for the occurrence of the spontaneous combustion: the Pt particle size is below 5.8 nm, and the hydrogen content in the carbon spheres is above 2.570 wt %. Such a reaction is interesting for the preparation of metal hollow spheres and is also relevant with respect to removal of accumulated carbon on catalysts and for soot oxidation at room temperature.  相似文献   

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