Enhanced Capacitive Performance Based on Diverse Layered Structure of Two-Dimensional Ti3C2MXene with Long Etching Time

2016 ◽  
Vol 163 (9) ◽  
pp. A1975-A1982 ◽  
Author(s):  
Yi Tang ◽  
JianFeng Zhu ◽  
ChenHui Yang ◽  
Fen Wang
2021 ◽  
Author(s):  
Tao Li ◽  
Xuefeng Chang ◽  
Lifang Mei ◽  
Xiayun Shu ◽  
Jidong Ma ◽  
...  

Ti3C2Tx is a promising new two-dimensional layered material for supercapacitors with good electrical conductivity and chemical stability. However, Ti3C2Tx has problems such as collapse of the layered structure and low...


2016 ◽  
Vol 72 (6) ◽  
pp. 480-484 ◽  
Author(s):  
Qiu-Ying Huang ◽  
Xiao-Yi Lin ◽  
Xiang-Ru Meng

The N-heterocyclic ligand 2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole (imb) has a rich variety of coordination modes and can lead to polymers with intriguing structures and interesting properties. In the coordination polymercatena-poly[[cadmium(II)-bis[μ-benzene-1,2-dicarboxylato-κ4O1,O1′:O2,O2′]-cadmium(II)-bis{μ-2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole}-κ2N2:N3;κ2N3:N2] dimethylformamide disolvate], {[Cd(C8H4O4)(C11H10N4)]·C3H7NO}n, (I), each CdIIion exhibits an irregular octahedral CdO4N2coordination geometry and is coordinated by four O atoms from two symmetry-related benzene-1,2-dicarboxylate (1,2-bdic2−) ligands and two N atoms from two symmetry-related imb ligands. Two CdIIions are connected by two benzene-1,2-dicarboxylate ligands to generate a binuclear [Cd2(1,2-bdic)2] unit. The binuclear units are further connected into a one-dimensional chain by pairs of bridging imb ligands. These one-dimensional chains are further connected through N—H...O hydrogen bonds and π–π interactions, leading to a two-dimensional layered structure. The dimethylformamide solvent molecules are organized in dimeric pairsviaweak interactions. In addition, the title polymer exhibits good fluorescence properties in the solid state at room temperature.


2021 ◽  
Author(s):  
Jamie W. Gittins ◽  
Chloe J. Balhatchet ◽  
Yuan Chen ◽  
Cheng Liu ◽  
David G. Madden ◽  
...  

Two-dimensional electrically conductive metal-organic frameworks (MOFs) have emerged as promising model electrodes for use in electric double-layer capacitors (EDLCs). However, a number of fundamental questions about the behaviour of this class of materials in EDLCs remain unanswered, including the effect of the identity of the metal node and organic linker molecule on capacitive performance and the limitations of current conductive MOFs in these devices relative to traditional activated carbon electrode materials. Herein, we address both these questions via a detailed study of the capacitive performance of the framework Cu<sub>3</sub>(HHTP)<sub>2</sub> (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) with an acetonitrile-based electrolyte, finding a specific capacitance of 110 – 114 F g<sup>−1</sup> at current densities of 0.04 – 0.05 A g<sup>−1</sup> and a modest rate capability. By, directly comparing its performance with the previously reported analogue, Ni<sub>3</sub>(HITP)<sub>2</sub> (HITP = 2,3,6,7,10,11-hexaiminotriphenylene), we illustrate that capacitive performance is largely independent of the identity of the metal node and organic linker molecule in these nearly isostructural MOFs. Importantly, this result suggests that EDLC performance in general is uniquely defined by the 3D structure of the electrodes and the electrolyte, a significant finding not demonstrated using traditional electrode materials. Finally, we probe the limitations of Cu<sub>3</sub>(HHTP)<sub>2</sub> in EDLCs, finding a limited cell voltage window of 1.3 V and only a modest capacitance retention of 81 % over 30,000 cycles, both significantly lower than state-of-the-art porous carbons. These important insights will aid the design of future conductive MOFs with greater EDLC performances.


2019 ◽  
Author(s):  
Roberto Köferstein

Triclinic single crystals of Cu2(H2O)4[C4H4N2][C6H2(COO)4]·2H2O have been grown in anaqueous silica gel. Space group P-1 (Nr. 2), a = 723.94(7) pm, b = 813.38(14) pm, c = 931.0(2) pm, α = 74.24(2)°, β = 79.24(2)°, γ = 65.451(10)°, V = 0.47819(14) nm3, Z = 1. Cu2+ is coordinated in a distorted, octahedral manner by two water molecules, three oxygen atoms ofthe pyromellitate anions and one nitrogen atom of pyrazine (Cu—O 194.1(2)–229.3(3) pm;Cu–N 202.0(2) pm). The connection of Cu2+ and [C6H2(COO)4)]4− yields infinite strands,which are linked by pyrazine molecules to form a two-dimensional coordination polymer.Thermogravimetric analysis in air showed that the dehydrated compound was stable between175 and 248 °C. Further heating yielded CuO.


2016 ◽  
Vol 30 (20) ◽  
pp. 1650256 ◽  
Author(s):  
Xuebo Yuan ◽  
Guochang Lin ◽  
Youshan Wang

Thermal cloaks have potential applications in thermal protection and sensing, and those cloaks with complex shapes are much more efficient in application. Layered discretization is a valid way to realize thermal cloaks designed through spatial transformation which are usually nonhomogeneous and anisotropic. However, previous studies are limited to two-dimensional cylindrical ones. Based on the theories of spatial transformation and effective medium, a four-step design method for layered structure of thermal cloak with complex shape is proposed. It is expected to realize the designed layered structure by utilizing the existing regular materials. According to the numerical simulations, the thermal cloaking performances of layered structures are good and close to that of the perfect thermal cloaks. This study has provided an effective way for realizing thermal cloak with complex shape.


2015 ◽  
Vol 27 (4) ◽  
pp. 1529-1531 ◽  
Author(s):  
Ye-Wen Wu ◽  
Jian-Teng Wang ◽  
Chang Jiang ◽  
Wen-Xiang Chai ◽  
Li Song

2013 ◽  
Vol 69 (11) ◽  
pp. 1344-1347 ◽  
Author(s):  
Patricio Cancino ◽  
Evgenia Spodine ◽  
Verónica Paredes-García ◽  
Diego Venegas-Yazigi ◽  
Andrés Vega

In the structure of the title compound, {[Cu2(C10H2O8)(H2O)6]·4H2O}n, the benzene-1,2,4,5-tetracarboxylate ligand, (btec)4−, is located on a crystallographic inversion centre in a μ4-coordination mode. The coordination environment of each pentacoordinated CuIIcentre is square pyramidal (SBP), formed by three water molecules and two carboxylate O atoms from two different (btec)4−ligands. The completely deprotonated (btec)4−ligand coordinates in a monodentate mode to four CuIIatoms. The alternation of (btec)4−ligands and SBP CuIIcentres leads to the formation of a planar two-dimensional covalent network of parallelograms, parallel to theabplane. Hydrogen bonds between a basal water molecule and an apical one from an adjacent [Cu(btec)0.5(H2O)3] unit exist in the intralayer space. Hydrogen bonds are also present between the two-dimensional network and the water molecules filling the channels in the structure.


Sign in / Sign up

Export Citation Format

Share Document