共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
Force‐field based grand‐canonical Monte Carlo simulations are used to investigate the acetylene and carbon dioxide uptake capacity, as well as the C2H2/CO2 adsorption selectivity of three novel microporous materials: Magnesium formate, Cu3(btc)2, and cucurbit[6]uril. Because no comparable computational studies of acetylene adsorption have been reported so far, the study focuses on systems for which experimental data are available to permit a thorough validation of the simulation results. The results for magnesium formate are in excellent agreement with experiment. The simulation predicts a high selectivity for acetylene over CO2, which can be understood from a detailed analysis of the structural features that determine the affinity of Mg‐formate towards C2H2. For Cu3(btc)2, preliminary calculations reveal the necessity to include the interaction of the sorbate molecules with the unsaturated metal sites, which is done by means of a parameter adjustment based on ab‐initio calculations. In spite of the high C2H2 storage capacity, the C2H2/CO2 selectivity of this material is very modest. The simulation results for the porous organic crystal cucurbit[6]uril show that the adsorption characteristics that have been observed experimentally, particularly the very high isosteric heat of adsorption, cannot be understood when an ideal structure is assumed. It is postulated that structural imperfections play a key role in determining the C2H2 adsorption behavior of this material, and this proposition is supported by additional calculations. 相似文献
3.
4.
A Rod‐Packing Microporous Hydrogen‐Bonded Organic Framework for Highly Selective Separation of C2H2/CO2 at Room Temperature 下载免费PDF全文
Peng Li Dr. Yabing He Dr. Yunfeng Zhao Prof. Dr. Linhong Weng Dr. Hailong Wang Prof. Dr. Rajamani Krishna Prof. Dr. Hui Wu Prof. Dr. Wei Zhou Prof. Dr. Michael O'Keeffe Prof. Dr. Yu Han Prof. Dr. Banglin Chen 《Angewandte Chemie (International ed. in English)》2015,54(2):574-577
Self‐assembly of a trigonal building subunit with diaminotriazines (DAT) functional groups leads to a unique rod‐packing 3D microporous hydrogen‐bonded organic framework (HOF‐3). This material shows permanent porosity and demonstrates highly selective separation of C2H2/CO2 at ambient temperature and pressure. 相似文献
5.
Shuai Gu Yunlong Zhu Prof. Guipeng Yu Chunyue Pan Prof. Zhonggang Wang Yuehua Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(38):13357-13363
A novel metal‐doping strategy was developed for the construction of iron‐decorated microporous aromatic polymers with high small‐gas‐uptake capacities. Cost‐effective ferrocene‐functionalized microporous aromatic polymers (FMAPs) were constructed by a one‐step Friedel–Crafts reaction of ferrocene and s‐triazine monomers. The introduction of ferrocene endows the microporous polymers with a regular and homogenous dispersion of iron, which avoids the slow reunion that is usually encountered in previously reported metal‐doping procedures, permitting a strong interaction between the porous solid and guest gases. Compared to ferrocene‐free analogues, FMAP‐1, which has a moderate BET surface area, shows good gas‐adsorption capabilities for H2 (1.75 wt % at 77 K/1.0 bar), CH4 (5.5 wt % at 298 K/25.0 bar), and CO2 (16.9 wt % at 273 K/1.0 bar), as well as a remarkably high ideal adsorbed solution theory CO2/N2 selectivity (107 v/v at 273 K/(0–1.0) bar), and high isosteric heats of adsorption of H2 (16.9 kJ mol?1) and CO2 (41.6 kJ mol?1). 相似文献
6.
Microporous organic polymers offer the possibility of storing hydrogen safely at low temperatures and moderate pressures via physisorption. A range of polymers of intrinsic microporosity (PIMs) have been studied. The best PIM to date is based on a triptycene monomer and takes up 2.7% H2 by mass at 10 bar/77 K. Hypercrosslinked polymers (HCPs) also show promising performance, particularly at pressures >10 bar. The form of the H2 isotherm is influenced by the micropore distribution, a higher concentration of ultramicropores (pore size <0.7 nm), as found in PIMs, being associated with enhanced low pressure adsorption. The performance of polymers relative to other microporous materials (carbons and metal‐organic frameworks) is compared and promising methods to enhance the hydrogen uptake of microporous polymers are suggested.
7.
Prof. Xue Han Prof. Sihai Yang 《Angewandte Chemie (International ed. in English)》2023,62(20):e202218274
Since its first industrial production in 1890s, acetylene has played a vital role in manufacturing a wide spectrum of materials. Although current methods and infrastructures for various segments of acetylene industries are well-established, with emerging functional porous materials that enabled desired selectivity toward target molecules, it is of timely interest to develop new efficient technologies to promote safer acetylene processes with a higher energy efficiency and lower carbon footprint. In this Minireview, we, from the perspective of materials chemistry, review state-of-the-art examples of advanced porous materials, namely metal–organic frameworks and decorated zeolites, that have been applied to the purification and storage of acetylene. We also discuss the challenges on the roadmap of translational research in the development of new solid sorbent-based separation technologies and highlight areas which require future research efforts. 相似文献
8.
Na型层状锰氧化物于0.1 mol/L HCl 溶液中离子交换制得前驱体H型层状锰氧化物. H型层状锰氧化物在十二胺乙醇溶液中反应得到层间距为2.62 nm的中间产物——十二胺插入的层状锰氧化物, 该中间产物在异丙醇钛和乙醇的混合溶液中溶剂热处理得到层间距为1.24 nm的钛酸柱撑层状锰氧化物. 在300 ℃条件下经2 h焙烧得到二氧化钛铸型氧化锰微孔材料. 应用XRD, DSC-TGA, SEM, TEM, IR, 氮气吸附实验及元素分析进行了不同阶段所得试样的分析表征. 结果表明十二胺分子在锰氧层间的最大插入量为2.2 mmol/g, 异丙醇钛分子的置换插入生成了组成为Mn7.00Ti1.74O23.3(C12H25NH2)0.52•1.93H2O的铸型层状锰氧化物. 300 ℃焙烧处理所得二氧化钛铸型氧化锰微孔材料的比表面积为140 m2/g. 相似文献
9.
Ken‐ichi Sawamura Dr. Teruaki Izumi Kiyotoshi Kawasaki Shintaro Daikohara Tetsu Ohsuna Prof. Mitsuko Takada Dr. Yasushi Sekine Prof. Eiichi Kikuchi Prof. Masahiko Matsukata Prof. 《化学:亚洲杂志》2009,4(7):1070-1077
Sort the bigs from the smalls : Reverse‐selective membranes, through which bigger molecules selectively permeate, are attractive for developing chemical processes. A new adsorption‐based reverse‐selective membrane that utilizes a Na cation occluded in a zeolitic framework is presented. The membrane developed enables the selective permeation and separation of bigger polar molecules, such as methanol and water, from hydrogen above 473 K.
10.
11.
Microporous metal–organic frameworks (MOFs) are comparatively new porous materials. Because the pores within such MOFs can be readily tuned through the interplay of both metal‐containing clusters and organic linkers to induce their size‐selective sieving effects, while the pore surfaces can be straightforwardly functionalized to enforce their different interactions with gas molecules, MOF materials are very promising for gas separation. Furthermore, the high porosities of such materials can enable microporous MOFs with optimized gas separation selectivity and capacity to be targeted. This Focus Review highlights recent significant advances in microporous MOFs for gas separation. 相似文献
12.
微孔材料理论模拟的进展与展望 总被引:1,自引:0,他引:1
微孔材料是指孔径小于2 nm的多孔材料, 被广泛应用于非均相催化、吸附、分离、储气等先进工艺中. 按照组成结构分类, 由于这些材料在元素组成及结构特征上的多样性, 因此原则上能够合成的此类材料数目巨大. 仅通过实验手段无法有效地对这些具有潜在应用价值的材料进行研究. 随着计算机资源与数值计算方法的迅速发展, 理论计算方法研究微孔材料不仅可以提供分子水平上对材料特性的认知, 而且可以从微观尺度上揭示实验机理, 有利于建立结构与性能的对应关系, 从而推动新型微孔材料的设计与开发. 综述了近年来针对各种类型微孔材料的理论研究方法及最新的理论研究成果. 指出了理论方法在微孔材料研究进程中存在的主要问题、发展前景及今后的研究方向. 相似文献
13.
Kadhum J. Msayib Dr. David Book Dr. Peter M. Budd Dr. Nhamo Chaukura Kenneth D. M. Harris Prof. Madeleine Helliwell Dr. Steven Tedds Allan Walton Dr. John E. Warren Dr. Mingcan Xu Dr. Neil B. McKeown Prof. 《Angewandte Chemie (International ed. in English)》2009,48(18):3273-3277
Quick on the uptake : Following its identification during a targeted search, the intriguing crystal structure of 3,3′,4,4′‐tetra(trimethylsilylethynyl)biphenyl was investigated. Simple removal of the included solvent provides an organic crystal with an open microporous structure that has a striking similarity to that of zeolite A (see picture). Reversible adsorption of nitrogen and hydrogen gases at 77 K confirms that the microporosity is permanent.
14.
降低工业分离过程的能耗为缓解全球能源紧缺问题提供了有效途径. 相比传统工业分离技术, 膜分离技术能耗低、经济效益高, 开发高效的膜材料是提升膜分离性能的重要手段. 共轭微孔聚合物(CMP)膜具有刚性永久超微孔道、高孔隙率、孔结构及化学环境可调控、交联骨架稳定性好等优势, 在分离领域具有良好的应用前景. 概述了近年来CMP膜的制备方法并简要对比了其优缺点, 阐述了CMP膜在气体分离、有机溶剂纳滤、离子筛分和手性分离等领域的分离机理和研究进展, 为开发新型具有良好分离性能的CMP膜材料提供研究思路. 相似文献
15.
Microporous Polymers from a Carbazole‐Based Triptycene Monomer: Synthesis and Their Applications for Gas Uptake 下载免费PDF全文
Tian‐Long Zhai Dr. Liangxiao Tan Yi Luo Dr. Jun‐Min Liu Prof. Dr. Bien Tan Prof. Xiang‐Liang Yang Prof. Hui‐Bi Xu Dr. Chun Zhang 《化学:亚洲杂志》2016,11(2):294-298
Two kinds of novel organic microporous polymers TCP s ( TCP‐A and TCP‐B ) were prepared by two cost‐effective synthetic strategies from the monomer of tricarbazolyltriptycene ( TCT ). Their structure and properties were characterized by FT‐IR, solid 13C NMR, powder XRD, SEM, TEM, and gas absorption measurements. TCP‐B displayed a high surface area (1469 m2 g?1) and excellent H2 storage (1.70 wt % at 1 bar/77 K) and CO2 uptake abilities (16.1 wt % at 1 bar/273 K), which makes it a promising material for potential application in gas storage. 相似文献
16.
Conductive Microporous Covalent Triazine‐Based Framework for High‐Performance Electrochemical Capacitive Energy Storage 下载免费PDF全文
Yajuan Li Shuanghao Zheng Xue Liu Pan Li Dr. Lei Sun Ruixia Yang Sen Wang Prof. Dr. Zhong‐Shuai Wu Prof. Dr. Xinhe Bao Prof. Dr. Wei‐Qiao Deng 《Angewandte Chemie (International ed. in English)》2018,57(27):7992-7996
Nitrogen‐enriched porous nanocarbon, graphene, and conductive polymers attract increasing attention for application in supercapacitors. However, electrode materials with a large specific surface area (SSA) and a high nitrogen doping concentration, which is needed for excellent supercapacitors, has not been achieved thus far. Herein, we developed a class of tetracyanoquinodimethane‐derived conductive microporous covalent triazine‐based frameworks (TCNQ‐CTFs) with both high nitrogen content (>8 %) and large SSA (>3600 m2 g?1). These CTFs exhibited excellent specific capacitances with the highest value exceeding 380 F g?1, considerable energy density of 42.8 Wh kg?1, and remarkable cycling stability without any capacitance degradation after 10 000 cycles. This class of CTFs should hold a great potential as high‐performance electrode material for electrochemical energy‐storage systems. 相似文献
17.
18.
Jumei Tian Wenliang Li Dr. Bo Li Xiaoying Zhang Prof. Jinkui Tang Prof. Jingping Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(16):5097-5103
We have synthesized a microporous magnetic framework that contained supertetrahedral decametallic cobalt clusters as nodes and 4‐(tris(hydroxymethyl)methyl)pyridine ligands as linkers in a NaCl‐like network. This complex shows canted antiferromagnetism with spin‐glass behavior. After the removal of the guest molecules, the spin‐canting and spin‐glass behaviors are maintained. The permanent porosity was evaluated by N2‐adsorption measurements. This complex mainly shows a hydrophobic nature, as validated by MeOH‐ and water‐adsorption measurements, which is consistent with the grand canonical Monte Carlo (GCMC) theoretical simulation. 相似文献
19.