Endohedral fullerene studies are the fascinating one, particularly with Carbon 60 and Carbon 70. Water molecules inside fullerenes alter their cage structure, reorientations make them to play a lot in charge distribut...Endohedral fullerene studies are the fascinating one, particularly with Carbon 60 and Carbon 70. Water molecules inside fullerenes alter their cage structure, reorientations make them to play a lot in charge distribution. In this line we are presenting our work on Carbon 70 with three water molecules inside. Ab initio SCF calculations are carried out for the fullerene Carbon 70 and Carbon 70 with three water molecules. Carbon 70 is a rugby ball structure, when three water molecules are added inside it, dissociation of charges takes place. Unusual flip flop circular hydrogen bond formation takes place inside Carbon 70. The dipole moment of endohedral C70 with three water molecules has been found to be 0.53 Debye, 0.49 Debye and 0.71 Debye respectively for STO-3G, 3-21G and 6-31G basis sets. Total energies for this molecule are reported in addition to the Hydrogen bond length and bond angles of the three water molecules trapped inside C70.展开更多
Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)s...Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)spheres,used as anode material for lithium ion batteries,were successfully fabricated by Stober method.XRD patterns reveal that Fe3O4@TiO2@C Y-S spheres possess a good crystallinity.But the diffraction peaks’intensity of Fe3O4 crystals in the composites is much weaker than that of bare Fe3O4 spheres,indicating that the outer anatase TiO2@C layer can cover up the diffraction peaks of inner Fe3O4 spheres.The yolk-shell structure of Fe3O4@TiO2@C spheres is further characterized by TEM,HAADFSTEM,and EDS mapping.The yolk-shell structure is good for improving the cycling stability of the inner Fe3O4 spheres during lithium ions insertion-extraction processes.When tested at 200 mA/g,the Fe3O4@TiO2@C Y-S spheres can provide a stable discharge capacity of 450 mAh/g over 100 cycles,which is much better than that of bare Fe3O4 spheres and TiO2@C spheres.Furthermore,cyclic voltammetry curves show that the composites have a good cycling stability compared to bare Fe3O4 spheres.展开更多
A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, ...A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, was obtained under a mild synthesis condition. The titled compound is crystallized in a monoclinic system, space group P2(1)/c with a=1.584 7(7) nm, b=1.426 7(6) nm, c=1.936 3(6) nm, β=113.186(7)°, V=4.024 6(3) nm 3, Z=4, D X=1.947 mg/m 3, M r=1 179.92, μ=1.662 mm -1, F(000)=2 344, R=0.074 8, wR=0.215 1. Three cadmium centers link with each other through BDC or BTC ligand to form a 3-D open framework.展开更多
文摘Endohedral fullerene studies are the fascinating one, particularly with Carbon 60 and Carbon 70. Water molecules inside fullerenes alter their cage structure, reorientations make them to play a lot in charge distribution. In this line we are presenting our work on Carbon 70 with three water molecules inside. Ab initio SCF calculations are carried out for the fullerene Carbon 70 and Carbon 70 with three water molecules. Carbon 70 is a rugby ball structure, when three water molecules are added inside it, dissociation of charges takes place. Unusual flip flop circular hydrogen bond formation takes place inside Carbon 70. The dipole moment of endohedral C70 with three water molecules has been found to be 0.53 Debye, 0.49 Debye and 0.71 Debye respectively for STO-3G, 3-21G and 6-31G basis sets. Total energies for this molecule are reported in addition to the Hydrogen bond length and bond angles of the three water molecules trapped inside C70.
基金supported by the Tianjin Committee of Science and Technology (No.14JCZDJC32400)Tianjin Science and Technology Innovation Platform Program (No.14TXGCCX00017)
文摘Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)spheres,used as anode material for lithium ion batteries,were successfully fabricated by Stober method.XRD patterns reveal that Fe3O4@TiO2@C Y-S spheres possess a good crystallinity.But the diffraction peaks’intensity of Fe3O4 crystals in the composites is much weaker than that of bare Fe3O4 spheres,indicating that the outer anatase TiO2@C layer can cover up the diffraction peaks of inner Fe3O4 spheres.The yolk-shell structure of Fe3O4@TiO2@C spheres is further characterized by TEM,HAADFSTEM,and EDS mapping.The yolk-shell structure is good for improving the cycling stability of the inner Fe3O4 spheres during lithium ions insertion-extraction processes.When tested at 200 mA/g,the Fe3O4@TiO2@C Y-S spheres can provide a stable discharge capacity of 450 mAh/g over 100 cycles,which is much better than that of bare Fe3O4 spheres and TiO2@C spheres.Furthermore,cyclic voltammetry curves show that the composites have a good cycling stability compared to bare Fe3O4 spheres.
文摘A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, was obtained under a mild synthesis condition. The titled compound is crystallized in a monoclinic system, space group P2(1)/c with a=1.584 7(7) nm, b=1.426 7(6) nm, c=1.936 3(6) nm, β=113.186(7)°, V=4.024 6(3) nm 3, Z=4, D X=1.947 mg/m 3, M r=1 179.92, μ=1.662 mm -1, F(000)=2 344, R=0.074 8, wR=0.215 1. Three cadmium centers link with each other through BDC or BTC ligand to form a 3-D open framework.
