模板法中孔炭材料的制备与表征

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（FTIR）、低温N2自动吸附、扫描电镜（SEM）、甲醛和VB12饱和吸附等对材料的结构及性能进行了测试与表征。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。     

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。     

模板法壳聚糖基介孔碳材料的制备与表征

以壳聚糖为碳前驱体、正硅酸乙酯为模板硅源,利用模板法制备了介孔碳材料。通过N2吸附/脱附、XRD、TEM等手段对介孔碳结构进行了表征。考察了溶液pH值和硅碳比对介孔碳孔结构的影响,介孔碳对维生素B12的吸附性能。结果表明,介孔碳材料孔隙发达、呈蠕虫状孔结构;溶液pH值为4、硅碳比为0.9时,介孔碳的比表面积、孔容及平均孔径分别达到1 118 m²/g,1.48 cm2/g,1.48 cm³/g及5.3 nm;对VB_(12)分子的吸附过程符合Langmuir单分子层吸附模型,最大平衡吸附量达到417.8 mg/g,2 h吸附量达到平衡吸附量的87.4%。     

模板法壳聚糖基介孔碳材料的制备与表征

以壳聚糖为碳前驱体、正硅酸乙酯为模板硅源,利用模板法制备了介孔碳材料。通过N2吸附/脱附、XRD、TEM等手段对介孔碳结构进行了表征。考察了溶液pH值和硅碳比对介孔碳孔结构的影响,介孔碳对维生素B12的吸附性能。结果表明,介孔碳材料孔隙发达、呈蠕虫状孔结构;溶液pH值为4、硅碳比为0.9时,介孔碳的比表面积、孔容及平均孔径分别达到1 118 m~2/g,1.48 cm~3/g及5.3 nm;对VB_(12)分子的吸附过程符合Langmuir单分子层吸附模型,最大平衡吸附量达到417.8 mg/g,2 h吸附量达到平衡吸附量的87.4%。     

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。     

3DOM SH-SiO2材料的制备及对Pb(Ⅱ)离子的吸附性能研究

以正硅酸乙酯为硅源,聚苯乙烯(Ps)胶晶为模板,MPTMS为功能化试剂制备出巯基改性3DOM二氧化硅.用SEM、TEM、FTIR和EDS等手段对其结构性质进行了表征,并对巯基改性3DOM SiO2进行了Pb2+吸附研究,实验结果:功能化材料为三维有序大孔结构,孔径为160 nm,材料中含硫4.17％.吸附剂用量、吸附时...     

溶胶-凝胶法碳源对多孔炭材料孔隙结构的影响

以正硅酸乙酯(TEOS)为模板硅源,β-环状糊精和可溶性淀粉分别为碳前驱体,运用溶胶-凝胶法制备了多孔炭材料。利用低温N2等温吸脱附、X射线衍射、高倍扫描电子显微镜等对所得炭材料的结构进行了测试与表征,结果表明,β-环糊精为碳源的样品主要孔径分布在2~3 nm;以可溶性淀粉为碳源的样品孔径呈双峰分布,即孔径集中在3.7 nm和5~20 nm,但由于炭化温度较低,所得的炭材料仍为无定形结构。     

模板法合成介孔碳的研究

蔗糖为碳前躯体,正硅酸乙酯(TEOS)为无机前躯体,三嵌段聚合物P123(聚(丙二醇)-嵌-聚(乙二醇)-嵌-聚(丙二醇))为模板剂,在酸性体系中,三组分共组装制备纳米复合材料,脱硅处理后得到介孔炭。对介孔碳材料做了BET、SEM表征分析。结果表明,制备出的介孔碳材料规整有序且平均孔径为4.4nm左右。     

溶胶凝胶法N,N-二甲基甲酰胺对多孔炭孔隙结构的影响

以正硅酸乙酯(TEOS)为模板硅源,蔗糖为碳前体,添加N,N-二甲基甲酰胺(DMF)作为控制干燥化学助剂(DCCA),运用溶胶凝胶(Sol-Gel)法制备多孔炭材料。通过SEM和低温N2等温吸脱附等手段对材料的结构进行了测试与表征,结果表明:在优选工艺条件后,成功地制得了无龟裂混合干凝胶,溶硅去模后多孔炭材料孔径主要集中分布在2～7nm。     

多级介孔炭对刚果红染料吸附性能的研究

以商业硅胶为模板,采用硬模板法制备了多级介孔炭,并研究了其对水溶液中刚果红染料的吸附性能.研究结果表明制备的多级介孔炭具有高比表面,大孔容和集中孔径分布以及高效吸附脱除刚果红染料的性能.多级介孔炭对水溶液中刚果红的吸附等温线符合Langmuir吸附模型,且在45℃具有最大吸附量,为446.89mg·g-1.吸附动力学研究表明动力学数据遵循拟二级动力学模型.热力学研究发现,在25～45℃内,刚果红在多级介孔炭上的吸附行为时吸热过程,且是自发进行的.     

Synthesis and characterization of mesoporous graphite carbon,and adsorption performance for benzene

In this paper, graphite carbon with a mesoporous structure was synthesized using the template–catalysis procedure with hydrated metal oxide nanoparticle as template and catalyst, phenol and formaldehyde as carbon source. XRD, Raman, BET and TEM analyses were performed to study the effluence of synthetic conditions on the structure of samples. The adsorption performances for benzene vapor were evaluated. The results show that CCo and CFe samples have mesoporous graphitized carbon structures. The molar amount of template to carbon source significantly affects the specific surface area, pore structure and adsorption–desorption performance. The specific surface area of CCo-1, with the best graphite structure, was 287.638 m²/g, the pore size was 19.075 nm, and the adsorption capacity for benzene vapor was 19.615 mmol/g. The synergistic effect between the cobalt element and graphite carbons affects the adsorption capacity of CCo-3, which was 34.643 mmol/g. However, the desorption efficiency was only 89 %, and the adsorption performance of CCo-3 material was degraded greatly after three times run.     

中孑L分布活性炭的制备与表征

以酚醛树脂为前驱体,纳米SiO2为模板剂,采用模板炭化和钾碱活化工艺研制中孔率较高、比表面积较大的中孔炭（Mesoporous carbon,MC）,考察了活化温度、活化时间、树脂模板比等工艺参数对活性炭孔结构的影响。测试了活性炭N2的吸附等温线、孔径分布、比表面积,并通过扫描电子显微镜观察其微观结构。结果表明,较优工艺条件为：树脂模板比为2：1、活化温度850℃、活化时间3h,该条件下所得中孔炭中孔率达91．4％,比表面积为1501m^2·g^-1,总孔孔容1．38m^2·g^-1,为理想的窄孔径分布活性炭。     

Zr-SBA-15催化苯酚甲醛高选择性合成邻位异构体双酚F

以P₁₂₃为模板剂,正硅酸乙酯为硅源,以硝酸氧锆为锆源,采用水热一步法合成了分子筛催化剂Zr-SBA-15,用XRD、BET、ICP、吡啶FT-IR、NH₃-TPD进行了分析表征,考察了不同Si/Zr摩尔比Zr-SBA-15催化苯酚、甲醛合成双酚F的催化活性,发现当Si/Zr摩尔比为20时催化活性较好。以Si/Zr摩尔比20的Zr-SBA-15为催化剂,在反应温度90℃、酚醛摩尔比30:1、催化剂与甲醛质量比1:1条件下反应240 min,双酚F收率达到83.5%,邻位异构体双酚F选择性高达92.5%,同时还提出了Zr-SBA-15高选择性催化苯酚、甲醛合成邻位异构体双酚F的反应机理。     

酚醛树脂基高度有序介孔炭材料的合成及其电容性

以碱性条件下制备出的A阶酚醛树脂为炭前驱体,三元嵌段共聚物P123及F127为介孔模板剂,采用乙醇溶剂蒸发诱导自组装与程序升温策略,制备出高度有序、比表面积达550.12 m2/g、孔容为0.385 4 cm3/g、平均孔径为3.97 nm的酚醛树脂基有序介孔炭材料。利用小角X射线衍射、扫描电镜、透射电镜、物理吸附及电化学性能测试等技术,研究了不同合成条件下得到的有序介孔炭材料的结构和电化学性能。结果表明,在6 mol/L KOH电解质溶液的三电极体系中,该优化有序介孔炭材料在1 A/g的电流密度下比电容可达146.5 F/g。     

A low-temperature autoclaving route to synthesize monolithic carbon materials with an ordered mesostructure

Low-temperature autoclaving has been demonstrated to synthesize monolithic carbon materials with an ordered mesostructure by using triblock copolymer F127 as template, and resorcinol/formaldehyde resol as carbon precursor under acidic conditions. Transmission electron microscopy, small angle X-ray scattering, Fourier transform infrared spectroscopy and nitrogen adsorption measurements show that the crack-free carbon monoliths have a 2-D hexagonal pore system, a uniform pore size of ∼5.0 nm and a high surface area of ∼675 m² g⁻¹. The macroscopic morphology can be tuned by changing the diameter of the autoclave. The influence of the synthesis conditions including the autoclaving treatment time and the molar ratio of formaldehyde (F) to resorcinol (R) are discussed. It is found that while the F/R molar ratio ?2 and the autoclaving treatment time ?2 d, highly ordered mesoporous carbon monoliths can be obtained. In comparison, monolithic mesoporous carbon materials prepared through an evaporation-induced self-assembly strategy are partly cracked with a disordered wormhole-like mesostructure, suggesting that low-temperature autoclaving is an efficient way to prepare crack-free monolithic carbon materials with an ordered mesostructure.     

Simple synthesis of highly ordered mesoporous carbon by self-assembly of phenol–formaldehyde and block copolymers under designed aqueous basic/acidic conditions

In view of the low reactivity of phenol with formaldehyde under acidic condition in the synthesis of ordered mesoporous carbons, a strategy to accelerate the polymerization of phenol and formaldehyde by using designed aqueous basic/acidic conditions (first weakly basic condition then highly acidic condition) is developed. The first weakly basic condition benefits the formation of hydroxymethyl phenols at 313 K. The latter highly acidic condition mainly induces the condensation reaction between the formed hydroxymethyl phenols, as well as the self-assembly of phenol–formaldehyde and block copolymer template. After removal of the template, the obtained carbon exhibits highly ordered hexagonal mesostructure with a surface area of 760 m² g⁻¹, large pore volume (0.64 cm³ g⁻¹) and uniform pore size (3.32 nm). This developed strategy affords a simple and highly reproducible approach for the synthesis of ordered mesoporous carbon from the less expensive phenol under strong acidic condition, which also provides a wide and easily accessed synthesis condition for the further functionalization, such as the in situ introducing of metal ions.     

Synthesis and characterization of porous media produced by a sol-gel method

Mesoporous silica materials were synthesized by sol-gel method using tetraethoxysilane (TEOS) as precursors and surfactants i.e., cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and polyoxyethylene cetyl ether (Brij 56) as templates. Surfactant templates were completely removed by calcination to form mesoporous structure. The effects of type and amount of surfactants on the characteristics of samples were studied. The textural characteristics such as surface area, pore volume, pore size, and pore size distribution were determined by nitrogen sorption isotherms. Fourier transform infrared (FTIR) spectroscopy was employed to qualitatively identify the chemical functionality and to confirm the removal of surfactant template. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to directly observe surface morphology and mesoporous structure, respectively. The adsorption capacity of the synthesized adsorbent for toluene vapor was examined. We found that the pore volume and pore size of mesoporous materials affected the adsorption capacity. The sample prepared with high content of CTAB under basic condition (pH ∼7) yielded large pore volumes and pore sizes and subsequently possessed the high adsorption capacity for toluene vapor.