壳聚糖原位合成复合炭材料及表征

以壳聚糖、导电剂(PbO)为原料,利用原位合成方法,制备了复合炭材料。利用X射线粉末衍射仪、扫描电子显微镜和电子能谱仪、比表面仪、拉曼光谱仪等对复合炭材料的组成、结构和形貌进行表征。结果表明,壳聚糖为碳源的复合炭材料具有非晶态结构,活性炭与导电剂相容性良好,孔径分布集中在5~10 nm,,比表面积高达487.4 m~2/g。壳聚糖比炭黑更适合作炭材料的碳源。     

Na型Y沸石为模板制备多孔炭材料的研究

以Na型Y沸石分子筛为模板,糠醇为碳源,制备了微孔模板炭材料.用热重分析研究了样品的热重行为,用N<,2>吸附表征了样品的比表面积和孔结构特征.研究表明,采用此方法得到了比表面积最大为826 m<'2>/g的模板炭材料,且孔径均一,分布主要集中在1.1 nm和1.6 nm.     

K_2CO_3活化制备淀粉基碳分子筛

以可溶性淀粉为碳源、三嵌段共聚物F127为模板剂和K_2CO_3为活化剂,采用一步合成法制备系列淀粉基碳分子筛。通过扫描电子显微镜和N_2吸附-脱附分析淀粉基碳分子筛孔隙形貌和孔结构,采用热重-TG和傅里叶红外光谱表征原料和样品的物质结构官能团。结果表明,K_2CO_3浓度、F127添加比例、反应时间和反应温度影响淀粉基碳分子筛的孔隙结构。在炭化温度800℃、K_2CO_3浓度为0.50 mol·L~(-1)、F127与淀粉质量比=1∶3、反应温度50℃和反应时间12 h条件下制备的淀粉基碳分子筛,孔径集中于0.63 nm,比表面积为1 069.290 4 m~2·g~(-1),单点孔容0.667 901 cm~3·g~(-1)。     

中孔炭材料的制备及吸附性能的研究

以正硅酸乙酯为模板硅源，酚醛树脂为炭前驱体，运用模板法制备了中孔炭材料。并用红外光谱（FT—IR）、扫描电镜（SEM）、低温N2自动吸附、甲醛和VB12饱和吸附等对样品形貌、孔结构和吸附性能进行了研究。结果表明：制备的炭材料孔径集中分布在2-7nm左右，且中孔孔隙率达到74．6％，比表面积达到1012m^2／g；材料对VB12大分子有较好的吸附性能。表明通过控制正硅酸乙酯的水解条件能制备孔径集中的中孔炭材料。     

碳材料吸附脱除二氧化硫性能的影响因素

选用了7种不同物理化学特性的碳材料,分别为活性炭-1 (比表面积1779m²/g)、活性炭-2 (比表面积970m²/g)、多孔纳米炭-1 (平均孔径14nm)、多孔纳米炭-2 (平均孔径85nm)、多孔纳米炭-3 (平均孔径4.7nm,掺氮)、多孔纳米炭-4 (平均孔径4.1nm,不掺氮)和纳米碳纤维。在对比这7种不同的碳材料的物理化学特性与其脱硫性能的基础上,研究材料的物理化学特性、脱硫温度、反应空速等因素对碳材料吸附脱除SO₂性能的影响。结果表明,碳材料吸附脱除SO₂的性能受材料的比表面积、孔隙结构、表面官能团、脱硫温度和反应空速的综合影响。不同的碳材料中,材料的孔隙结构和表面官能团对材料的脱硫性能影响很大,以微孔结构为主的碳材料SO₂去除率较高,以介孔结构为主的碳材料脱硫容量较高;随着脱硫温度升高,碳材料的吸附脱硫性能降低;随着反应空速降低,碳材料的吸附脱硫性能升高。本研究中,多孔纳米炭NCP-10的吸附脱除SO₂性能最好,能在室温下保持100%的...     

基于预沥青烯的有序结构中孔炭及其电化学性能

以预沥青烯为碳源、SBA-15为模板,采用模板法合成了结构有序的中孔炭材料。用XRD、TEM、N₂吸附和电化学工作站等对中孔炭的微观结构及电化学性能进行了研究。结果表明,以预沥青烯为碳源合成的炭材料具有高度有序的二维六方孔道和一定的石墨化程度,它反转复制了模板SBA-15的结构。中孔炭的比表面积为542 m²·g^-1,孔容为0.479 cm³·g^-1,孔径呈单峰分布,集中在3.5 nm左右。这种预沥青烯基中孔炭作为电化学电容器电极材料,显示出良好的性能,在1 mA的电流强度下其单电极质量比电容高达310 F·g^-1。     

淀粉为碳源制备铅炭电池负极材料的研究

以氨水+二氧化碳脱硫的脱硫铅膏为原料、淀粉为碳源,进行糊化活化后,在氮气保护下置于管式炉中煅烧制备铅炭材料。考察了淀粉与铅膏的质量比、煅烧温度、煅烧时间对产物的影响,并利用热重分析(TGA)、X射线衍射(XRD)、透射电镜(TEM)等分析手段对产物的成分、形貌、结构和粒径分布进行分析,结果表明,淀粉与铅膏质量比为1∶1时,在450℃下煅烧2.5 h制得的铅炭样品基本无团聚现象,铅或铅的氧化物颗粒均匀地分散在碳基质中,粒径分布窄,平均粒径为11.69 nm,为制备优质的铅炭电池负极材料提供了一种新的途径。     

溶胶凝胶法多孔炭材料的制备及其表征

以十六烷基三甲基溴化胺(CTAB)稳定过的商业硅溶胶为模板硅源、蔗糖为炭前体、运用溶胶凝胶法制备了多孔炭材料。并采用低温N2等温吸脱附、X射线衍射等对材料的结构进行了测试与表征。结果表明:CTAB的加入使所得的多孔炭孔径分布更加集中,由于炭化温度较低,所得的炭材料仍为无定形结构。     

以线性酚醛树脂为炭前驱体制备有序介孔炭及其表征

以三嵌段共聚物F127和P123为模板剂,线性酚醛树脂(PF)为炭前驱体,利用有机-有机自组装制备了具有二维六方结构和蠕虫结构的介孔炭.采用XRD、TEM、N2吸附/脱附等方法对介孔炭的结构进行了表征,研究了模板剂用量和模板剂类型对上述介孔炭结构的影响.结果表明:当模板剂F127与PF的质量比由1:2变为1:1时,所得介孔炭的孔壁厚度有所下降,但比表面积、孔容和孔径分别从576 m2·g-1、0.29 cm3·g-1和2.7 nm提高到670m2·g-1、0.40 cm3· g-1和3.2 nm;分别以F127和P123为模板剂制备的介孔炭F-1-500和P-1-500的孔径大小基本相同,但P-1-500的孔壁厚度相对于F-1-500降低了37.4％,且有序性下降,仅能得到蠕虫状结构.     

MCM-41介孔碳材料的合成及其电化学性能

以十六烷基三甲基溴化铵(CTAB)为模板剂,可溶性淀粉(Starch)为碳源,通过软模板法一步合成了高度有序的介孔碳材料。通过热重分析(TG)、X射线衍射(XRD)、N2吸附-脱附和透射电子显微镜(TEM)对材料的结构进行了表征。结果表明:当m(模板剂CTAB)∶m(可溶性淀粉)=1.0∶1.5,650℃焙烧碳化3 h,并用氢氟酸去除二氧化硅后,所得到的MCM-41有序介孔碳材料(OMC-650)的比表面积为985 m2/g,平均孔径为2.5nm,且孔径分布均匀。XRD和TEM分析结果表明,OMC-650具有典型的MCM-41结构特征,有序性良好。以OMC-650作为工作电极,氧化汞为参比电极,铂为辅助电极,用6 mol/L KOH做电解液,测其比电容为150 F/g,且经过1 000次充放电循环后,其比电容仍为138 F/g,为原电容的92%,说明所合成的材料具有良好的电容稳定性。     

Direct fabrication of mesoporous carbons using in-situ polymerized silica gel networks as a template

Mesoporous carbons were synthesized by in-situ polymerized silica gel networks as a template. The co-condensation of carbon precursor (sucrose) and silica precursor (sodium silicate) followed by heat treatment generated a carbon/silica nanocomposite. After etching the silica template, mesoporous carbons were obtained. Under optimum synthesis conditions a mesoporous carbon with a high surface area of >800 m²/g and a narrow pore size distribution centered at 3 nm was produced. The three-dimensionally interconnected silica structures effectively functioned as the template for the porous carbon materials.     

Synthesis of ultra-large mesoporous carbons from triblock copolymers and phloroglucinol/formaldehyde polymer

Ultra-large mesoporous carbon materials were synthesized with the use of triblock copolymers and phloroglucinol/formaldehyde polymer as filler under acid conditions. The carbons obtained by employing F127 as template and carbonizing at 600 °C exhibit large mesopores with a narrow pore-size distribution centered at 19.2 nm. With the assistance of decane as a swelling agent, the pore size of the P123-templated 600 °C-carbonized carbons could be enlarged from 11.5 to 14.7 nm. It is demonstrated that the low synthesis temperature and high reactivity of phloroglucinol are two key factors for the formation of large mesopores.     

胶体晶体模板法制备三维有序排列的大孔SiO2材料

将粒径为480 nm的聚苯乙烯微球离心组装为胶体晶体模板,以正硅酸乙酯为硅源配制SiO₂溶胶并填充到模板间隙,原位形成凝胶,最后通过焙烧去除模板,得到三维有序大孔（3DOM）SiO₂。通过SEM检测,大孔以六方有序的方式排列,其孔径及孔径收缩率分别为360 nm和25％。大孔之间由小窗口连通,构成内部三维交联的大孔网络。低温N₂吸附测试表明,大孔孔壁上存在中孔孔隙,其中在3～4 nm有一集中的孔分布。XRD显示,制备的3DOM材料由无定形SiO₂组成。     

有序介孔碳材料的模板化构筑及水处理应用研究

介孔碳材料是指孔径介于2 nm-50 nm的一类多孔碳材料。有序介孔碳材料，具有比表面积高、孔道结构规则有序、孔径分布狭窄、孔径大小可调控、表面易于修饰等结构特点和高机械强度、强吸附能力、化学惰性等性能特点，在诸多领域得到了广泛应用，特别是其作为新型吸附剂在水处理领域具有广阔的发展前景。有序介孔炭材料的制备方法主要有硬模板法和软模板法。模板和碳源的选择是控制有序介孔碳材料结构和性能的关键因素。本文从有序介孔硅、天然矿物、MOFs材料、嵌段共聚物等不同模板的角度对有序介孔碳、多级有序微/介孔碳、多级有序大/介孔碳的制备方法进行综述，并对有序介孔碳材料在水处理领域的应用进行简单介绍。     

溶胶-凝胶法制备中孔炭材料及其表征

以正硅酸乙酯为无机模板硅源，蔗糖为炭前驱物，采用溶胶-凝胶法制得了比表面积达1073．36m^2／g，孔径分布集中，平均孔径为2．75nm的中孔炭材料，并采用FT—IR、N2吸附、TG—DTA和XRD等分析手段对其进行了表征。     

Methane sorption on ordered mesoporous carbon in the presence of water

An ordered mesoporous carbon was synthesized using SBA-15 as the template. The sorption isotherms of methane on the synthesized carbon material were collected. Its ordered structure was confirmed by the XRD, SEM and TEM examinations. The BET surface area is 1100-1200 m²/g, the total pore volume is 1.24-1.30 cm³/g, and the pore size distribution is very narrow and centered at 2-5 nm. As high as 41.2 wt.% of methane was stored per unit mass of carbon at 275 K and pressures less than 7 MPa in the presence of 3.86 times more water. This sorption amount is 31% higher than the largest sorption capacity reached by activated carbon in the presence of water, which was equal to or higher than the storage capacity of compression till 20 MPa. The enthalpy change corresponding to the sudden change of isotherms was equal to the enthalpy change of methane hydrate formation; therefore, the mechanism of the enhanced methane storage was considered due to the formation of methane hydrate in the porous carbon material.     

Ordered mesoporous carbon prepared from triblock copolymer/novolac composites

Ordered mesoporous carbon is synthesized by the organic–organic self-assembly method with novolac as carbon precursor and two kinds of triblock copolymers (Pluronic F127 and P123) as template. The hexagonal structure and a worm-hole structure are observed by TEM. The carbonization temperature is determined by TG and FT-IR. Characterization of physical properties of mesoporous carbon is executed by N₂ absorption–desorption isotherms and XRD. The mass ratios of carbon precursor/template affect the textural properties of mesoporous carbon. The mesoporous carbon with F127/PF of 1/1 has lager surface area (670 m² g^?1), pore size (3.2 nm), pore volume (0.40 cm³ g^?1), smaller microporous surface area (368 m² g^?1) and wall thickness (3.7 nm) compare to that with F127/PF of 0.5/1 (576 m² g^?1, 2.7 nm, 0.29 cm³ g^?1, 409 m² g^?1 and 4.3 nm, respectively). The mesoporous carbon prepared by carbonization at high temperature (700 °C) exhibits lager surface area, lower pore size and pore volume than the corresponding one obtained at 500 °C. The structure and order of the resulting materials are notably affected with types of templates. The mesoporous carbon with P123 as template exhibits worm-hole structure compare to that with F127 as template with hexagonal structure. In general, the pore size of mesoporous carbon with novolac as precursor is smaller than that with resorcinol–formaldehyde as precursor.     

Worm-hole structured mesoporous carbon monoliths synthesized with amphiphilic triblock copolymer

In the present work, mesoporous carbon monoliths with worm-hole structure had been synthesized through hydrothermal reaction by using amphiphilic triblock copolymer F127 and P123 as templates and resole as carbon precursor. Synthesis conditions, carbonization temperature and pore structure were studied by Fourier transform infrared, thermogravimetric analysis, transmission electron microscopy and N₂ adsorption–desorption. The results indicated that the ideal pyrolysis temperature of the template is 450 °C. The organic ingredients were almost removed after further carbonized at 600 °C and the mesoporous carbon monoliths with worm-hole structure were obtained. The mesoporous carbon synthesized with P123 as single template exhibited larger pore size (6.6 nm), higher specific surface area (747 m² g^?1), lower pore ratio (45.9 %) in comparison with the mesoporous carbon synthesized with F127 as single template (with the corresponding value of 4.9 nm, 681 m² g^?1, 49.6 %, respectively), and also exhibited wider pore size distribution and lower structure regularity. Moreover, the higher mass ratio of template P123/resole induced similar pore size, larger specific surface area and lower pore ratio at the same synthesizing condition. It was also found that the textural structure of mesoporous carbon was affect by calcination atmosphere.     

高比表面积三维有序大孔炭材料的合成与表征

将粒径为540nm的SiO2胶体微球通过自然沉积组装为胶体晶体模板,以葡萄糖的水溶液为前体填充模板间隙,高温炭化后,以HF溶液溶去模板,得到三维有序大孔炭材料。根据SEM检测,大孔以六方有序的方式排列,其孔径及孔径收缩率分别为510nm和5.6%。大孔之间由小窗口连通,构成内部三维交联的大孔网络。低温N2吸附测试表明,大孔孔壁上存在2～10nm为主的中孔孔隙,同时由于前体的表面复制作用,使样品BET比表面积达到948m2/g。XRD表征显示,所制备的3DOM材料由无序石墨结构的炭质组成。