通过溶胶-凝胶超临界干燥技术制备出NiO/SiO2比为1.2的二元气凝胶纳米催化剂,并以气凝胶为催化剂通过化学气相热解法合成了碳纳米管;碳纳米管的合成是在石英管式炉中完成.将催化剂置于石英舟中,在流动氮气中将管式炉加热至所需的温度,然后通入甲烷、氢气混合气体,热解反应30min～60min后形成碳纳米管.反应结束后,生成的碳纳米管在氮气氛中冷却至室温.采用XRD、SEM、TEM、HRTEM、Raman分析手段对制得的碳纳米管进行了表征,并测定其磁化系数.结果表明:裂解产物主要由碳纳米管和纳米镍粒子组成,且纳米镍粒子包覆于碳纳米管的顶端.这种包覆纳米镍粒子的碳纳米管的比饱和磁化强度和矫顽力分别为0.66A·m2·kg-1和20157A·m-1.
Multi-walled carbon nanotubes were synthesized by the catalytic chemical vapor decomposition method, and a binary aerogel with a 1.20∶1 nickel-silica weight ratio was used as catalyst, which was prepared by the sol-gel supercritical fluid drying method. The synthesis of carbon nanotub es was conducted in a quartz tube furnace. The catalysts in the quartz boat were heat-treated to the required temperature under nitrogen atmosphere and reduced by flowing hydrogen for 30min. Then the gas mixture of hydrogen and methane was introduced into the furnace and pyrolyzed for 30min～60min. Finally, the product obtained was cooled to room temperature under a nitrogen atmosphere. The samples were characterized by XRD, SEM, TEM, HRTEM, Raman spectra and susceptib ility tests. The results showed that the pyrolytic product was composed of multi -walled carbon nanotubes and nanosized nickel particles, which were encapsulated at the tip of the carbon nanotubes. Magnetic analysis showed that the carbon nanotubes encapsulating nickel had a specific saturation magnetization of 0.66A ·m2·kg-1 and a coercivity of 20157A·m-1.
参考文献
| [1] | Iijima S .Helical Microtubules of Griphitic Carbon[J].Nature,1991,354:56-58. |
| [2] | Frank S;Poncharal P;Wang Z L et al.Carbon nanotube quantum resistors[J].Science,1998,280:1744-1746. |
| [3] | Philippe Poncharal;Z.L. Wang;Daniel Ugarte .Electrostatic deflections and electromechanical resonances of carbon nanotubes[J].Science,1999(5407):1513-1516. |
| [4] | Deheer WA;Chatelain A;Ugarte D .A CARBON NANOTUBE FIELD-EMISSION ELECTRON SOURCE[J].Science,1995(5239):1179-1180. |
| [5] | Chen J;Hamon M A;Hu H et al.Solution properties of single-walled carbon nanotubes[J].Science,1998,282:95-98. |
| [6] | A. C. Dillon;K. M. Jones;T. A. Bekkedahl;C. H. Kiang;D. S. Bethune;M. J. Heben .STORAGE OF HYDROGEN IN SINGLE-WALLED CARBON NANOTUBES[J].Nature,1997(6623):377-379. |
| [7] | Tans S J;Devoret M H;Dai H et al.Individual single-wall carbon nanotubes as quantum wires[J].Nature,1997,386:474-477. |
| [8] | Bandow S.;Saito Y.;Rao AM.;Grigorian L.;Richter E.;Eklund PC.;Asaka S. .Effect of the growth temperature on the diameter distribution and chirality of single-wall carbon nanotubes[J].Physical review letters,1998(17):3779-3782. |
| [9] | Fan S S;Chaplin M G;Franklin N F et al.Self-oriented regular arrays of carbon nanotubes and their field emission properties[J].Science,1999,283:512-514. |
| [10] | Collins PG.;Zettl A. .UNIQUE CHARACTERISTICS OF COLD CATHODE CARBON-NANOTUBE-MATRIX FIELD EMITTERS[J].Physical Review.B.Condensed Matter,1997(15):9391-9399. |
| [11] | Bonard J M;Salvetat J P;Stockli T et al.Field emission from single-wall carbon nanotube films[J].Applied Physics Letters,1998,73:918-921. |
| [12] | Tans SJ.;Verschueren ARM.;Dekker C. .Room-temperature transistor based on a single carbon nanotube[J].Nature,1998(6680):49-52. |
| [13] | Niu C;Sichel E K;Hoch R et al.High power elec trochemical capacitors based on carbon nanotube electrodes[J].Physics Letters,1997,70:1480-1483. |
| [14] | DIEDERICH L;Barborini E;Piseri P et al.Superc apacitors based on nanostructured carbon electrodes grown by cluster beam deposition[J].Applied Physics Letters,1999,75:2662-2665. |
| [15] | An KH.;Park YS.;Choi YC.;Lee SM.;Chung DC.;Bae DJ.;Lim SC. Lee YH.;Kim WS. .Supercapacitors using single-walled carbon nanotube electrodes[J].Advanced Materials,2001(7):497-500. |
| [16] | Frackowiak E;Gautier S;GAUCHER H et al.Electr ochemical storage of lithium in multiwalled carbon nanotubes[J].Carbon,1999,37:37,61. |
| [17] | Liu C;Fan Y Y;Liu M et al.Hydrogen storage in single-walled carbon nanotubes at room temperature[J].Science,1999,286:1127-1129. |
| [18] | Cheng HM.;Liu C.;Yang QH. .Hydrogen storage in carbon nanotubes [Review][J].Carbon: An International Journal Sponsored by the American Carbon Society,2001(10):1447-1454. |
| [19] | Fan Y Y;Liao B;Liu M et al.Hydrogen uptake in vapor-growncarbon nanofibers[J].Carbon,1999,37:1649-1652. |
| [20] | 毛宗强,徐才录,阎军,梁吉,孙公敏,魏秉庆,吴德海.碳纳米纤维储氢性能初步研究[J].新型炭材料,2000(01):64-67. |
| [21] | 沈建其,何少龙,王新庆,王淼.单壁纳米碳管储氢机制研究[J].新型炭材料,2001(02):24-26,65. |
| [22] | Ajayan P M;Schadler L S;Giannaris C et al.Mec hanical response of singlewalled carbon nanotubes in polymer nanocomposites[J].Advanced Materials,2000,12:750. |
| [23] | 沈曾民,赵东林.镀镍碳纳米管的微波吸收性能研究[J].新型炭材料,2001(01):1-4. |
| [24] | 王敏炜,李凤仪,彭年才.碳纳米管--新型的催化剂载体[J].新型炭材料,2002(03):75-79. |
| [25] | 李玉宝,解思深,周维亚,王刚,魏秉庆,吴德海.碳纳米管对Fe-P非晶的力学性能和晶化行为影响的研究[J].新型炭材料,2000(03):7-12. |
| [26] | 贾志杰,徐才录,梁吉,魏秉庆,吴德海,朱绍文.关于尼龙-6/炭纳米管复合材料的研究[J].新型炭材料,1999(02):32-36. |
| [27] | Ago H;Th Kugler;Cacialli F et al.Work functions and surface functional groups of multiwall carbon nanotubes[J].Journal of Physical Chemistry B,1999(103):8116-8121. |
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