As a new two-dimensional layered structural material,Ti_(3)C_(2)T_(x)has excellent electrical conductivity,mechanical properties,hydrophilicity and rich functional groups,showing a wide application prospect in the fie...As a new two-dimensional layered structural material,Ti_(3)C_(2)T_(x)has excellent electrical conductivity,mechanical properties,hydrophilicity and rich functional groups,showing a wide application prospect in the field of energy storage.However,when Ti_(3)C_(2)T_(x)is used as the electrode material of energy storage device,it is easy to stack due to the van der Waals forces between the layers,which hinders the reaction between the surface active site and electrolyte ions,lengthens the path of ion diffusion,and affects its specific capacity and rate performance.To address the above problems,this paper summarizes the research progress of Ti_(3)C_(2)T_(x)surface modification including designing three-dimensional nanostructures,constructing intercalated structural composites(composite with monomers,oxides,sulfides,and selenides),and doping with heteroatoms in sodium-ion batteries,and describes in detail the strategies or mechanisms of battery performance enhancement in conjunction with its preparation methods.Finally,its future research direction and development prospects are envisioned.展开更多
Two phase transition materials[iPrQ]2MnBr4(1,iPrQ=N-isopropyl-quinuclidinium)and[iPrQ]_(2)MnCl_(4)(2)were synthesized and characterized.Dielectric measurements and differential scanning calorimetry showed that the two...Two phase transition materials[iPrQ]2MnBr4(1,iPrQ=N-isopropyl-quinuclidinium)and[iPrQ]_(2)MnCl_(4)(2)were synthesized and characterized.Dielectric measurements and differential scanning calorimetry showed that the two compounds underwent reversible phase transitions at ca.–47 and–37℃,respectively.Variable-temperature single-crystal X-ray diffraction suggested that the two compounds underwent the same phase transitions from space group C2/c to Cc but at different temperature.The variable crystal structures indicated that the structural phase transitions of the compound were ascribed to the torsional movement of quinuclidine ring and the disappearance of the c-slide plane.The second harmonic generation(SHG)response further proved this structural phase transition.Fluorescence tests showed that the two compounds have strong fluorescence.The strong variations in dielectric anomalies make compounds 1 and 2 suitable for promising switchable dielectric materials.展开更多
基金supported by the Youth Science Foundation Project of National Natural Science Foundation of China(51802031)
文摘As a new two-dimensional layered structural material,Ti_(3)C_(2)T_(x)has excellent electrical conductivity,mechanical properties,hydrophilicity and rich functional groups,showing a wide application prospect in the field of energy storage.However,when Ti_(3)C_(2)T_(x)is used as the electrode material of energy storage device,it is easy to stack due to the van der Waals forces between the layers,which hinders the reaction between the surface active site and electrolyte ions,lengthens the path of ion diffusion,and affects its specific capacity and rate performance.To address the above problems,this paper summarizes the research progress of Ti_(3)C_(2)T_(x)surface modification including designing three-dimensional nanostructures,constructing intercalated structural composites(composite with monomers,oxides,sulfides,and selenides),and doping with heteroatoms in sodium-ion batteries,and describes in detail the strategies or mechanisms of battery performance enhancement in conjunction with its preparation methods.Finally,its future research direction and development prospects are envisioned.
基金supported by the National Natural Science Foundation of China(21671084)the Six talent peaks project in Jiangsu Province(2014-XCL-008)the Qing Lan Project of Jiangsu Province and the Foundation of Jiangsu Educational Committee(16KJB430011)。
文摘Two phase transition materials[iPrQ]2MnBr4(1,iPrQ=N-isopropyl-quinuclidinium)and[iPrQ]_(2)MnCl_(4)(2)were synthesized and characterized.Dielectric measurements and differential scanning calorimetry showed that the two compounds underwent reversible phase transitions at ca.–47 and–37℃,respectively.Variable-temperature single-crystal X-ray diffraction suggested that the two compounds underwent the same phase transitions from space group C2/c to Cc but at different temperature.The variable crystal structures indicated that the structural phase transitions of the compound were ascribed to the torsional movement of quinuclidine ring and the disappearance of the c-slide plane.The second harmonic generation(SHG)response further proved this structural phase transition.Fluorescence tests showed that the two compounds have strong fluorescence.The strong variations in dielectric anomalies make compounds 1 and 2 suitable for promising switchable dielectric materials.
