共查询到19条相似文献,搜索用时 62 毫秒
1.
《纤维素科学与技术》2017,(1)
介绍了纤维素碳气凝胶原材料的主要来源及各原材料的特点,重点举例阐述可直接利用型纤维素制备纤维素基碳气凝胶材料的不同工艺方法,综合分析了纤维素基碳气凝胶作为多功能材料的一些前沿的应用研究。总结了该领域存在的挑战并展望了纤维素基碳气凝胶的发展前景。 相似文献
2.
植物纤维素基碳气凝胶具有低密度、可生物降解、优异的吸附性能和电化学性能稳定等特点。本文围绕其原料来源、制备工艺及其在环境治理和能量储存与转化方面的应用,分析了植物纤维素基碳气凝胶的性能及研究进展。详细叙述了以棉花、木材、竹纤维等为原料的植物纤维素基碳气凝胶的制备方法,如:溶胶-凝胶法、水热炭化法、直接炭化法等。分析了制备过程中干燥方法、溶剂的选择及置换、复合改性等影响因素,并介绍了碳气凝胶在空气净化、油水分离、有毒化合物、重金属离子的去除等环境治理及能量转化与储存方面的。 相似文献
3.
4.
环境灾害、能源匮乏和不断涌现的生活新需求(如可弯曲便携式电子设备、混合动力汽车等),需要不断探索新材料以提升超级电容器的性能。活性炭以其可控的多孔结构、化学稳定性、高导电性而成为超级电容器电极主导材料。此背景下,从生物质中生产低成本的活性炭至关重要,生物质碳具备来源丰富、绿色再生、独特生物结构与较高离子迁移率等特性,还有助于减少对化石燃料的依赖,是目前各国科研人员的探究热点。本文从生物质碳资源方面着手,阐述了生物质的各种来源、生物炭合成方法,综述了生物质及其衍生生物炭在超级电容器和锂离子电池方面的应用研究。 相似文献
5.
7.
8.
通过与无机气凝胶对比,引入碳气凝胶的导电特性。简述了双电层电容器的基本工作原理,综述了碳气凝胶在双电层电容器电极材料方面的研究进展。总结了碳气凝胶电极制备过程中关键因素,并提出了一些研究展望。 相似文献
9.
10.
11.
Fabrication and Physical Properties of Organic and Carbon Aerogel Derived from Phenol and Furfural 总被引:1,自引:0,他引:1
Phenol can be used as a cheap raw material to prepare organic and carbon aerogels based upon the gelation and supercritical drying in ethanol. In addition, organic and carbon aerogels could also be obtained by directly drying phenol-furfural alco-gels at ambient pressure under proper preparation conditions. The effect of the preparation conditions, such as the phenol-furfural (PF) concentration, the mass ratio of HCl to phenol (HCl/P), the mole ratio of phenol to furfural (P/F) and the gelation temperature, on the gelation ability and the bulk density was studied. The aerogels obtained have a three-dimensional network that consists of approximately 20 nm particles, which define numerous mesopores with diameter less than 50 nm. Organic aerogels obtained have high BET surface areas of 267–503 m/g and large mesopore volumes of 0.657–2.734 cm/g. Carbonization generates numerous micropores of ca. 0.45 nm in diameters but impairs to some extent the mesopore structure. As a result, carbon aerogels have high BET surface areas of 507–561 m/g, large micropore volumes of 0.106–0.168 cm/g and small mesopore volumes of 0.505–0.710 cm/g relative to their organic aerogel precursors. XRD characterization indicates that carbon aerogels are more crystalline than activated carbon but less than graphite. 相似文献
12.
13.
《分离科学与技术》2012,47(17):2649-2658
Carbon aerogel (CA) and xerogel (CX) are proposed for pesticide adsorption as new carbon adsorbent materials. These materials are prepared by polycondensation of resorcinol and formaldehyde in Na2CO3 catalysis, followed by a drying step, in CO2 supercritical or normal conditions to obtain organic aerogel or xerogel, and a pyrolytic step to obtain CA or CX. Adsorption experiments were carried out in batch conditions under magnetic stirring. Adsorbent quantity and grain size, pH, and temperature, and alpha-cypermethrin concentration influence on the adsorption efficiency were considered. The optimum parameters were established to be as follows: 0.01 g adsorbent, d < 0.025 mm, and 318 K. In all cases, CA proved to be more efficient than CX for alpha-cypermethrin removal from water samples. Equilibrium (Langmuir and Freundlich isotherms), kinetics (pseudo-first- and pseudo-second-order, intra-particle diffusion, and liquid film diffusion models) and thermodynamics of the considered adsorption process were discussed in detail. Equilibrium was best described by the Langmuir isotherm, while the kinetic of the process was best described by the pseudo-second-order model. Thermodynamic parameters showed that alpha-cypermethrin adsorption is an endothermic process. 相似文献
14.
J. Wang M. Glora R. Petricevic R. Saliger H. Proebstle J. Fricke 《Journal of Porous Materials》2001,8(2):159-165
Carbon cloth reinforced RF (Resorcinol Formaldehyde) aerogel films have been produced with extremely high RC ratio (molar ratio of resorcinol to catalyst) or with no catalyst at all. The gels were subcritically dried. Carbon aerogel films were obtained by pyrolysis of the RF aerogel films. The structure of the composite porous films was investigated using infrared spectrometer, optical and electron scanning microscope. The IR measurements indicated that the bottom surface reflectance of the films is higher than the top surface. The microscopical pictures revealed that the bottom surface of the films has a denser structure than the top surface, and the presence of carbon cloth in the sol-gel process strongly influences the structure of the films. The carbon cloth fibers act as catalytic sites. The particles are more likely to form around the fibers instead of within the sol. This leads to a somewhat reduced specific surface area as was shown via N2 sorption and BET analysis.Using the 4-probe method the electrical conductivity of the carbon cloth reinforced carbon films was found to be higher than that of pure carbon aerogel films. 相似文献
15.
生物质气化是一种在高温氧化性介质作用下将生物质热分解为可燃性气体的热解技术。为了提高生物质气化过程中气化效率、调整可燃性气体组分的含量和去除焦油,通常需要采用不同气化介质、改变气化条件或添加不同的催化剂。本文重点综述了生物质气化所使用的介质和催化剂种类以及气化条件对气化气组分,主要是H2和CO的影响规律。最后对未来生物质气化研究进行了展望,提出了几个待研究解决的问题。 相似文献
16.
生物质气化是一种在高温氧化性介质作用下将生物质热分解为可燃性气体的热解技术。为了提高生物质气化过程中气化效率、调整可燃性气体组分的含量和去除焦油,通常需要采用不同气化介质、改变气化条件或添加不同的催化剂。本文重点综述了生物质气化所使用的介质和催化剂种类以及气化条件对气化气组分,主要是H2和CO的影响规律。最后对未来生物质气化研究进行了展望,提出了几个待研究解决的问题。 相似文献
17.
采用反相乳液聚合法成功制备炭气凝胶微球,研究了合成条件对凝胶时间的影响。利用所得产品吸附氯化钯溶液,探讨炭气凝胶微球对Pd2+的吸附性能。结果表明,通过调控合成条件可以实现对合成过程的有效控制,炭气凝胶微球对Pd2+有优异的吸附性能,吸附率最高可达99.2%。 相似文献
18.
19.
锂离子电池碳原子线负极材料的研究 总被引:1,自引:1,他引:0
碳原子线的制备是以马铃薯淀粉为固态碳源以Fe(NO3)3为催化剂前驱体,高温裂解制得。将其作为锂离子电池负极材料,碳原子线首次充放电容量分别为369.5mAh/g和999.4mAh/g,从第2次循环起,充放电效率开始提高,第10次达到94.3%,不可逆容量逐渐降低,可逆容量基本维持在约300mAh/g左右。显示出碳原子线负极具有良好的循环性能和可逆容量。 相似文献