氧化石墨插层纳米复合材料的制备研究进展

氧化石墨（GO）插层纳米复合材料是一种新型的纳米复合材料。介绍了氧化石墨的结构、制备方法和性质；重点论述了聚合物/氧化石墨插层纳米复合材料和无机物/氧化石墨插层纳米复合材料的制备研究进展，介绍了半导体氧化物/氧化石墨插层纳米复合材料。     

插层复合材料的光催化研究进展

综述了插层复合材料的插层机理、插层方法以及在光催化领域的研究进展。阐述了主体材料对复合材料光催化性能的影响及改性方法，并提出在光催化领域插层复合材料的发展趋势。     

插层法制备聚合物/粘土纳米复合材料及其应用进展

概述了聚合物／粘土纳米复合材料插层制备的新进展，根据插层机理和方法的差别，将插层法分为三类：（1）单体插层复合；（2）溶液中聚合物插层复合；（3）熔融聚合物插层复合。重点提出了利用双螺杆挤出机制备聚合物基纳米复合材料的新方法，展望了聚合物／粘土纳米复合材料的开发及其应用前景。     

熔盐法合成金属氯化物-石墨插层化合物的判据

研究了熔融盐状态下金属氯化物-石墨层间化合物的合成判据.根据插层反应热动力学及化学键理论,选取元素的电负性和离子势作为键参数,并设计键参数函数λ为客体材料的遴选判据.基于键参数函数图对金属氯化物发生插层反应的难易程度和产物稳定性进行理论预估.研究结果表明:键参数函数图中λ≤1.2区域内的金属氯化物在700℃以下即可发生插层反应,且所得产物较为稳定;在1.2≤λ≤1.8区域内相应的客体材料在低温下很难单独插入石墨层间,常与低熔点氯化物形成共熔体后一起插入石墨层间;在λ≥1.8区域内大多为碱金属氯化物和碱土金属氯化物,理论分析认为这类物质的插层反应不适宜采用熔盐法.     

纳米复合材料——石墨层间化合物研究进展

介绍了纳米复合材料--石墨层间化合物(GICs)的发展过程和研究现状,重点阐述了GICs纳米复合材料的制备方法和机理,总结了GICs纳米复合材料的膨化方法及其应用领域,并对材料的发展趋势进行了展望.     

第14届国际层间化合物会议在韩国首尔举行

第14届国际层间化合物会议（ISICl4）于2007年6月12日～15日在韩国首都首尔举行，会议主席为韩同梨花女子大学的Jin—Ho Choy教授。来自21个国家的300余名学者参加了此次大会。本次会议共收录462篇论文（其中87篇为口头报告）。与前几届会议相比，本次会议论文总数大幅度增加，     

纳米复合材料──石墨层间化合物(GICs)的电化学合成研究

本文调研了纳米复合材料─GICs(石墨层间化合物)的电化学法合成GICs的各种研究方法及利用水溶液进行电化学插层的可行性等.分析了GICs的性能,并阐明了当前可膨胀石墨的电化学法生产中存在的问题及可能的解决措施.     

纳米复合材料──石墨层间化合物(GICs)的电化学合成研究

本文调研了纳米复合材料─GICs(石墨层间化合物)的电化学法合成GICs的各种研究方法及利用水溶液进行电化学插层的可行性等.分析了GICs的性能,并阐明了当前可膨胀石墨的电化学法生产中存在的问题及可能的解决措施.      

插层法制备聚合物基纳米复合材料研究进展

聚合物基纳米复合材料具有常规聚合物基复合材料所没有的结构、形态以及较常规聚合物基复合材料具有更优异的力学性能、耐热性能和气体液体阻隔性能等而显示出重要的科学意义和应用前景。本文综述插层法制备聚合物基纳米复合材料近几年的研究进展情况，总结了层状硅酸盐结构、插层剂选择、制备方法等问题。对制备过程进行了热力学和动力学分析，介绍了纳米复合材料表征方法，并对纳米复合材料的性能和应用进行了讨论。     

碳纤维作宿主的三元插层化合物研究

以高模量碳纤维作宿主，采用熔融盐法分别合成了FeCl3-ZnCl2和CuCl2一NiCl2作插层剂的三元插层化合物，由x射线衍射分析得知：前者的插层效果要优于后者。采用8mm波衰减率测试系统测试了两种产物对8mm波的衰减，结果表明：经FeCl3-ZnCl2和CuCl2-NiCl2插层的碳纤维对8mm波的衰减率分别可达8dB和6dB。     

New trends in intercalation compounds

We review here some of the recent developments in intercalation compounds generally, with numerous examples taken from the literature on graphite intercalation compounds. Particular emphasis is given to research opportunities and new directions in this rapidly moving research field.     

Organometallic intercalation compounds of FeOCl

The layered transition metal oxyhalide FeOCl has been found to undergo direct intercalation by the organometallic molecular compounds ferrocene and cobaltocene. From x-ray powder diffraction studies, it has been shown that the Van der Waals gap between the FeOCl layers expands by roughly 5Å to accomodate the metallocene. With either metallocene, the data accurately fit a body centered orthorhombic unit cell. A structural model consistent with the observations is proposed, based on a simple shift of alternate FeOCl layers by one-half unit cell in the [101] direction (a-c diagonal) accompanied by the interlayer expansion. There is no evidence for ordering within the metallocene layers. The intercalation of ferrocene is especially significant because its first ionization potential (6.88 eV) is substantially higher than those of organometallic compounds previously intercalated into transition metal dichalcogenides.     

Conductivity problems in two dimensional intercalation compounds

The ionic conductivity of two dimensional alkali metal intercalation compounds depends on factors such as the ratio between the number of intercalated ions and available vacancies in the v.d.w. gap, the nature of the bonds in the host structure, the site geometry, the nature of the alcalin ion. The problems of the electrons lost by the alkali metal is discussed in light of new experimental results. A simple model assuming a delocalization in the conduction band of the host does not apply to all the systems. Two or more classes of intercalation compounds may exist.     

Ion exchange of intercalation compounds from WOP2O7 and intercalation ofn-alkylamines

Ion exchange of Na _x WOP₂O₇ ·nH₂O (x 1.4) prepared from WOP₂O₇ was attempted, using alkaline and alkaline earth ions. The degree of exchange was observed to be >50% at 90° C except for Mg²⁺. The basal spacing of ion-exchanged materials for the hydrated phase were dependent on the number of water molecules in the interlayer spaces, while those for the dehydrated phase increased with the size of ions in the interlayer spaces. The network of water molecules linked by the hydrogen bond in the interlayer spaces seems to determine the basal spacing. By the ion-exchange reaction,n-alkylammonium ions were intercalated into the interlayer spaces of Na _x WOP₂O₇ ·nH₂O (x 1.4) and Sn _x H _y WOP₂O₇ ·nH₂O (2x +y 0.5). In spite of the difference in the charge density of the host layer, a similar arrangement of alkyl chains in the interlayer spaces resulted, and neutral amines were considered to be intercalated as well as ammonium ions. Direct reaction ofn-alkylamine with WOP₂O₇ produced an intercalation compound without reduction of tungsten. The arrangement of the amines in the interlayer spaces is similar to that supposed to the ion-exchanged derivatives when heated at 140° Cin vacuo.     

分步插层法制备硝酸盐-硫酸-GIC

通过硫酸、硝酸或硝酸盐分步插层的方法,成功制备了硝酸/硝酸盐-硫酸-GIC三元石墨层间化合物.采用XRD、SEM和EDS对GIC的结构进行了研究.结果表明:与直接插层法相比,分步插层法有利于插层物质的插层反应,充分扩大石墨层间距,形成低阶石墨层间化合物,使膨胀效果更优,膨胀体积高达450mL/g以上;膨胀后GIC的孔结构均匀,层壁较薄,片层结构清晰,膨胀充分.同时,分步插层法能够降低实验操作的危险性,污染小,反应易于控制.     

Lithium intercalation in KxTi8O16 compounds

Several bronzes K_xTi₈O₁₆ have been prepared from K_1.64(1)Ti₈O₁₆ by means of oxidative reactions. These bronzes have been intercalated with lithium by electrochemical methods in order to test their performances as electrode materials in lithium rechargeable batteries. The main result is that although the maximum capacity (260 Ah kg⁻¹) is reached in the compound with the lowest potassium content, a low reversibility and high polarisation are obtained. Bronzes with intermediate potassium content are more attractive for applications in rechargeable lithium batteries. These compounds maintain an acceptable capacity (200 Ah kg⁻¹) while having high cyclability and low polarisation. The application should be addressed to anode materials rather than to cathode due to the low voltage (1.75 V) obtained during the intercalation reaction.     

Alloying effect on electronic structures of lithium intercalation compounds

The alloying effect on the electronic structures of spinel LiM_xMn_2−xO₄ (M=Ti, Cr, Mn, Fe, Co, Ni, Cu and Zn) has been investigated by the DV-Xα molecular orbital method. Following the addition of alloying element M, new M-3d bands in the density of states appeared additionally compared with that in pure LiMn₂O₄. As the new M-3d bands appeared, the new O-2p bands also emerged accordingly in the same positions around Fermi energy due to M–O interaction. If alloying element M leads to emergence of O-2p band in low energy position, withdrawal of Li electrons from this low O-2p band would results in high electrochemical cell voltage. The mechanism of high voltage occurrence due to alloying in lithium intercalation compounds can be attributed to the low oxygen levels near Fermi energy modified by neighbor alloying element.     

Effects of processing parameters on the structure and amount of intercalation of copper chloride-graphite intercalation compounds

Natural graphite powders were intercalated with copper chloride using gas phase reaction in this study. The effects of intercalation temperature, time, and the amount of intercalants on the structure and the amount of intercalation were investigated. An electron probe x-ray microanalyzer (EPMA) was used to quantitatively measure the copper concentration in copper chloride-graphite intercalation compounds. Only stage 1 and stage 2 structures were found in the present processing conditions and the stage structure is mainly determined by the reaction temperature. Results of EPMA quantitative measurement indicated that the amount of intercalation increased with increasing intercalation temperature. However, the amount of intercalation was independent of the reaction time due to the small particle size of graphite host materials.