As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)poss...As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.展开更多
Hardness, friction and wear characteristics of electrodeposited RE Ni W P B 4C PTFE composite coatings were studied, and the reason for these fine characteristics was explained in respect of structure. The results sho...Hardness, friction and wear characteristics of electrodeposited RE Ni W P B 4C PTFE composite coatings were studied, and the reason for these fine characteristics was explained in respect of structure. The results show that 1) the structure of RE Ni W P B 4C PTFE composite coatings experiences a transformation process from amorphous to mixture then to crystal as the heat treatment temperature rises; 2) incorporating of B 4C greatly increases the hardness of the coating; 3) the wear resistance of the coating is best with heat treatment for 1?h at 300?℃, which is greatly superior to that of the other traditional coatings.展开更多
Two novel polymeric complexes, [Gd（HsTCAS）（H2O）7]·4H2O 1 and [Gd（HsTCAS） （CH3COCH3）（H2O）6]·6H2O 2 （H4TCAS = p-sulfonatothiacalix[4]arene）, have been synthesized and characterized by single-crysta...Two novel polymeric complexes, [Gd（HsTCAS）（H2O）7]·4H2O 1 and [Gd（HsTCAS） （CH3COCH3）（H2O）6]·6H2O 2 （H4TCAS = p-sulfonatothiacalix[4]arene）, have been synthesized and characterized by single-crystal X-ray diffraction analyses. Complex 1 crystallizes in monoclinic, space group C2/m with a = 20.2308（12）, b = 19.0894（10）, c = 12.2448（7）A, β = 101.847（3）°, V = 4628.1（5）A^3, C24H43GdO27S8, Mr = 1169.25, Z = 4, Dc = 1.690 g/cm^3, F（000） = 2380,μ = 1.879 mm^-1, the final R = 0.0404 and wR = 0.1038 for 5127 observed reflections with I 〉 2σ（I）. Complex 2 is pseudo-isostructural with complex 1.展开更多
Compound(Ph_4P)[V_3MP_6](MPH_2=o-HOC_6H_4SH)was obtained by reaction of VCl_3 and Na_2MP in ethanol in the presence of Ph_4PBr.It is triclinic and crystallizes in space group P1,fw=1237.3,a=14.127(4), b=14.342(4),c=15...Compound(Ph_4P)[V_3MP_6](MPH_2=o-HOC_6H_4SH)was obtained by reaction of VCl_3 and Na_2MP in ethanol in the presence of Ph_4PBr.It is triclinic and crystallizes in space group P1,fw=1237.3,a=14.127(4), b=14.342(4),c=15.878(4);α=65.08(2),β=73.09(2),T=78.68(2)°;V=2781.3~3, Z=2,d_c=1.48 g/cm^3.Final R factor is 0.063.The three vanadium atoms are linearly arranged and bridged by the oxygen atoms and terminally chelated by the thiolato-atoms of the six MP^2-ligands in pseudo-S_6 symmetry.展开更多
Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide（PNO） and p-sulfonatothiacal...Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide（PNO） and p-sulfonatothiacalix[4]arene（H4TCAS4-）：[Ln2（PNO）2（H2O）10？（H2TCAS）2].[Ln2（H2TCAS）2（H2O）6（MeOH）2].2MeOH.12H2O（Ln = La,1;Nd,2）.Crystal data for complex 1：C31H51La2NO33S8,Mr = 1500.03,triclinic system,P 1 space group,with a = 11.732（2）,b = 15.007（3）,c = 15.262（3）,α = 78.05（3）,β = 80.77（3）,γ = 83.89（3）°,Z = 2,V = 2587.3（9）3,Dc = 1.925 g/cm3,μ = 2.051 mm-1,F（000） = 1500,the final R = 0.0300 and wR = 0.0823;and those for complex 2：C31H51Nd2NO33S8,Mr = 1510.69,triclinic system,P1 space group,with a = 11.719（2）,b = 14.941（3）,c = 15.157（3）,α = 78.03（3）,β = 80.84（3）,γ = 83.95（3）°,Z = 2,V = 2555.9（9）3,Dc = 1.963 g/cm3,μ = 2.436 mm-1,F（000） = 1512,the final R = 0.0493 and wR = 0.1267.There are two coordination environments of lanthanide ions.One is bridged by two PNO molecules forming a dimeric Ln ion in the O,O’-μ2 mode.The dinuclear ions are shrouded by two H2TCAS6-ions through coordination interactions and hydrogen bonds.The other coordination mode of Ln ions is a zigzag 1D chain linked by up-down H2TCAS6-ions.By the coordination capsules,the complexes form 2D zigzag-ladder structure coordination polymers.展开更多
2-（4-Decarboxydehydroabietyl）-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the ort...2-（4-Decarboxydehydroabietyl）-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the orthorhombic system, space group P212121 with a = 6.1351（5）, b = 14.8495（19）, c = 25.9050（2） A, V = 2360.0（4） A3, Z = 4, Mr = 414.57, Dc = 1.167 Mg/m^3, 2 = 0.71073 A,μ（MoKa） = 0.070 mm^-1, F（000） = 896, the final R = 0.0452 and wR = 0.1076 for 1647 observed reflections with I 〉 2σ（I）. There are five rings in the crystal structure of the title compound, but the oxadiazole ring is non-coplanar with the benzene ring D.展开更多
The title complex（C66H76O8·CH3CN） was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a = 22.384（13）, b = 13.413（7）,...The title complex（C66H76O8·CH3CN） was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a = 22.384（13）, b = 13.413（7）, c = 21.867（12）, β = 112.257（7）°, C68H78NO8, Mr = 1037.31, Dc = 1.133 g/cm3, V = 6076（6） 3, Z = 4, F（000） = 2224, μ（MoKa） = 0.073 mm-1, T = 296（2） K, 10276 independent reflections with 5469 observed ones（I 〉 2σ（I））, R = 0.0797 and wR = 0.2316 with GOF = 1.027（R = 0.1442 and wR = 0.2689 for all data）. The calixarene moiety maintains the symmetric cone conformation through intramolecular O–H···O hydrogen bonds. The inhibition of the strand transfer process of HIV-1 integrase of the title compound was also evaluated. Preliminary bioassays indicated that it has a low inhibition ratio（24.85%） at the concentration of 50 μM.展开更多
The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted oc...The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively.展开更多
Sodium-ion batteries have been deemed as a sustainable alternative to lithium-ion systems due to the abundance and affordability of sodium sources.Nevertheless,developing high-energy-density P2-type layered oxide cath...Sodium-ion batteries have been deemed as a sustainable alternative to lithium-ion systems due to the abundance and affordability of sodium sources.Nevertheless,developing high-energy-density P2-type layered oxide cathodes with long-term cycling stability poses challenges,stemming from irreversible phase transitions,structural degradation,and lattice oxygen instability during electrochemical cycling.Here,we propose a one-step NbB_(2)modification strategy that enhances both bulk and surface properties of Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes.By exploiting different techniques,we disclose that bulk Nb and B doping combined with a Nb-Transition Metal-BO_(3)surface layer reconstruction enable a reversible P2-OP4 phase transition and,meanwhile,improve anionic redox reversibility.In addition,Li^(+)migrates into alkali-metal layers and underpins the layered structure through the“pillar effect”,thereby facilitating the Na^(+)diffusion in Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes and retaining their structural integrity at high voltage.As a result,the modified cathodes achieve 93.6%capacity retention after 500 cycles at 1C and deliver specific capacities above 114 m A h g^(-1)at 10C within 2.0-4.3 V.Contrary to the previous studies reporting that OP4 phase are detrimental to the structural stability of layered cathodes,we experimentally validate that a well-regulated P2-OP4 phase transition is beneficial for structural and electrochemical stabilities.展开更多
The title compound (p-methylphenylbis(4, 4-dimethyl-6-hydroxycyclohexene-1-one-2-yl)methane) has been synthesized by the reaction of 4-methylbenzaldehyde and 5, 5-dimethyl-1, 3-cyclohexanedione in N,N-dimethylformamid...The title compound (p-methylphenylbis(4, 4-dimethyl-6-hydroxycyclohexene-1-one-2-yl)methane) has been synthesized by the reaction of 4-methylbenzaldehyde and 5, 5-dimethyl-1, 3-cyclohexanedione in N,N-dimethylformamide. Its structure was determined by single crystal X-ray diffraction. The Crystal is monoclinic, space group P21/a, a=0. 9304 (2)nm, b=1. 1754 (2)nm, c=2. 0134 (4)nm, β=102. 40(2)°, Mr= 382. 50, V=2. 1505 (7)nm3, Dc = 1. 181g/cm3, Z=4, μ(MoKα) = 0. 79cm-1, F(000) = 856.The structure was solved by direct methods, and refined by full-matris least-Squares method to a final R =0. 042 and Rw = 0. 045. The crystal structure shows that there are two conjugated enol form in the molecule.展开更多
A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na（H2O）2Y（H2O）6（DMF） （p-sulfonatothiaca lix[4]arene）]-9H2O is reported. The complex be...A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na（H2O）2Y（H2O）6（DMF） （p-sulfonatothiaca lix[4]arene）]-9H2O is reported. The complex belongs to the monoclinic system, space group P2 1/c, with a = 16.703（3）, b = 17.819（4）, c = 17.357（4）A, β = 106.23（3）°, Z = 4, V = 4960.0（17）A^3, Mr = 1304.08, Dc = 1.746 g/cm^3,μ= 1.624 mm^-1, F（000） = 2688, the final R = 0.0398 and wR = 0.1132 for 7534 observed reflections with I 〉 2σ（I）. One yttrium（Ⅲ） ion is coordinated by the thiacalixarene ligand via the sulfonato group, and also ligated by an oxygen atom of a DMF molecule occupying the cavity of thiacalixarene and six aqua ligands.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22178148 and 22278193)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.
文摘Hardness, friction and wear characteristics of electrodeposited RE Ni W P B 4C PTFE composite coatings were studied, and the reason for these fine characteristics was explained in respect of structure. The results show that 1) the structure of RE Ni W P B 4C PTFE composite coatings experiences a transformation process from amorphous to mixture then to crystal as the heat treatment temperature rises; 2) incorporating of B 4C greatly increases the hardness of the coating; 3) the wear resistance of the coating is best with heat treatment for 1?h at 300?℃, which is greatly superior to that of the other traditional coatings.
基金This work was supported by the National Natural Science Foundation of China,Natural Science Foundation of Fujian Province,and the Young Scientist Funds of Fujian Province (No. 2006F3130)
文摘Two novel polymeric complexes, [Gd（HsTCAS）（H2O）7]·4H2O 1 and [Gd（HsTCAS） （CH3COCH3）（H2O）6]·6H2O 2 （H4TCAS = p-sulfonatothiacalix[4]arene）, have been synthesized and characterized by single-crystal X-ray diffraction analyses. Complex 1 crystallizes in monoclinic, space group C2/m with a = 20.2308（12）, b = 19.0894（10）, c = 12.2448（7）A, β = 101.847（3）°, V = 4628.1（5）A^3, C24H43GdO27S8, Mr = 1169.25, Z = 4, Dc = 1.690 g/cm^3, F（000） = 2380,μ = 1.879 mm^-1, the final R = 0.0404 and wR = 0.1038 for 5127 observed reflections with I 〉 2σ（I）. Complex 2 is pseudo-isostructural with complex 1.
文摘Compound(Ph_4P)[V_3MP_6](MPH_2=o-HOC_6H_4SH)was obtained by reaction of VCl_3 and Na_2MP in ethanol in the presence of Ph_4PBr.It is triclinic and crystallizes in space group P1,fw=1237.3,a=14.127(4), b=14.342(4),c=15.878(4);α=65.08(2),β=73.09(2),T=78.68(2)°;V=2781.3~3, Z=2,d_c=1.48 g/cm^3.Final R factor is 0.063.The three vanadium atoms are linearly arranged and bridged by the oxygen atoms and terminally chelated by the thiolato-atoms of the six MP^2-ligands in pseudo-S_6 symmetry.
文摘Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide（PNO） and p-sulfonatothiacalix[4]arene（H4TCAS4-）：[Ln2（PNO）2（H2O）10？（H2TCAS）2].[Ln2（H2TCAS）2（H2O）6（MeOH）2].2MeOH.12H2O（Ln = La,1;Nd,2）.Crystal data for complex 1：C31H51La2NO33S8,Mr = 1500.03,triclinic system,P 1 space group,with a = 11.732（2）,b = 15.007（3）,c = 15.262（3）,α = 78.05（3）,β = 80.77（3）,γ = 83.89（3）°,Z = 2,V = 2587.3（9）3,Dc = 1.925 g/cm3,μ = 2.051 mm-1,F（000） = 1500,the final R = 0.0300 and wR = 0.0823;and those for complex 2：C31H51Nd2NO33S8,Mr = 1510.69,triclinic system,P1 space group,with a = 11.719（2）,b = 14.941（3）,c = 15.157（3）,α = 78.03（3）,β = 80.84（3）,γ = 83.95（3）°,Z = 2,V = 2555.9（9）3,Dc = 1.963 g/cm3,μ = 2.436 mm-1,F（000） = 1512,the final R = 0.0493 and wR = 0.1267.There are two coordination environments of lanthanide ions.One is bridged by two PNO molecules forming a dimeric Ln ion in the O,O’-μ2 mode.The dinuclear ions are shrouded by two H2TCAS6-ions through coordination interactions and hydrogen bonds.The other coordination mode of Ln ions is a zigzag 1D chain linked by up-down H2TCAS6-ions.By the coordination capsules,the complexes form 2D zigzag-ladder structure coordination polymers.
基金Supported by the Foundation of 100 Young and Middle-aged Discipline Leaders of Guangxi Province in the 21st century (No. 2004219)the Natural Science Foundation of Guangxi Province (No. 0731054)
文摘2-（4-Decarboxydehydroabietyl）-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the orthorhombic system, space group P212121 with a = 6.1351（5）, b = 14.8495（19）, c = 25.9050（2） A, V = 2360.0（4） A3, Z = 4, Mr = 414.57, Dc = 1.167 Mg/m^3, 2 = 0.71073 A,μ（MoKa） = 0.070 mm^-1, F（000） = 896, the final R = 0.0452 and wR = 0.1076 for 1647 observed reflections with I 〉 2σ（I）. There are five rings in the crystal structure of the title compound, but the oxadiazole ring is non-coplanar with the benzene ring D.
基金supported by the National Natural Science Foundation of China(No.21102003)National Students'Innovation and Entrepreneurship Training Program(No.201210361094)+1 种基金Scientific Research Foundation for the Introduction of TalentYoung Teachers Scientific Research Foundation of Anhui University of Science&Technology(11214,2012QNY27)
文摘The title complex（C66H76O8·CH3CN） was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a = 22.384（13）, b = 13.413（7）, c = 21.867（12）, β = 112.257（7）°, C68H78NO8, Mr = 1037.31, Dc = 1.133 g/cm3, V = 6076（6） 3, Z = 4, F（000） = 2224, μ（MoKa） = 0.073 mm-1, T = 296（2） K, 10276 independent reflections with 5469 observed ones（I 〉 2σ（I））, R = 0.0797 and wR = 0.2316 with GOF = 1.027（R = 0.1442 and wR = 0.2689 for all data）. The calixarene moiety maintains the symmetric cone conformation through intramolecular O–H···O hydrogen bonds. The inhibition of the strand transfer process of HIV-1 integrase of the title compound was also evaluated. Preliminary bioassays indicated that it has a low inhibition ratio（24.85%） at the concentration of 50 μM.
基金the Foundation of Returning Personal from Overseas Study of Jiangsu Education Department.
文摘The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively.
基金financially supported by the National Key R&D Program of China(2020YFA0406203)National Natural Science Foundation of China(92472115,52371225 and 52072008)+5 种基金Guangdong Basic and Applied Basic Research Foundation(2022B1515120070,2022A1515110816 and 2022A1515110596)the Large Scientific Facility Open Subject of Songshan Lake,Dongguan,Guangdong(KFKT2022A04)Jialin Xie Fund(E4546IU2)the open research fund of Songshan Lake Materials Laboratory(2023SLABFN02)The Major Science and Technology Infrastructure Project of Material Genome Big-science Facilities Platform supported by the Municipal Development and Reform Commission of Shenzhen also contributed to this researchthe allocation of beamtime at BL15U and BL02B02 beamlines at SSRF。
文摘Sodium-ion batteries have been deemed as a sustainable alternative to lithium-ion systems due to the abundance and affordability of sodium sources.Nevertheless,developing high-energy-density P2-type layered oxide cathodes with long-term cycling stability poses challenges,stemming from irreversible phase transitions,structural degradation,and lattice oxygen instability during electrochemical cycling.Here,we propose a one-step NbB_(2)modification strategy that enhances both bulk and surface properties of Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes.By exploiting different techniques,we disclose that bulk Nb and B doping combined with a Nb-Transition Metal-BO_(3)surface layer reconstruction enable a reversible P2-OP4 phase transition and,meanwhile,improve anionic redox reversibility.In addition,Li^(+)migrates into alkali-metal layers and underpins the layered structure through the“pillar effect”,thereby facilitating the Na^(+)diffusion in Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes and retaining their structural integrity at high voltage.As a result,the modified cathodes achieve 93.6%capacity retention after 500 cycles at 1C and deliver specific capacities above 114 m A h g^(-1)at 10C within 2.0-4.3 V.Contrary to the previous studies reporting that OP4 phase are detrimental to the structural stability of layered cathodes,we experimentally validate that a well-regulated P2-OP4 phase transition is beneficial for structural and electrochemical stabilities.
文摘The title compound (p-methylphenylbis(4, 4-dimethyl-6-hydroxycyclohexene-1-one-2-yl)methane) has been synthesized by the reaction of 4-methylbenzaldehyde and 5, 5-dimethyl-1, 3-cyclohexanedione in N,N-dimethylformamide. Its structure was determined by single crystal X-ray diffraction. The Crystal is monoclinic, space group P21/a, a=0. 9304 (2)nm, b=1. 1754 (2)nm, c=2. 0134 (4)nm, β=102. 40(2)°, Mr= 382. 50, V=2. 1505 (7)nm3, Dc = 1. 181g/cm3, Z=4, μ(MoKα) = 0. 79cm-1, F(000) = 856.The structure was solved by direct methods, and refined by full-matris least-Squares method to a final R =0. 042 and Rw = 0. 045. The crystal structure shows that there are two conjugated enol form in the molecule.
文摘A 2D coordination polymer built by sodium ion and water-soluble p-sulfonatothiacalix[4]arene of trivalent yttrium complex [Na（H2O）2Y（H2O）6（DMF） （p-sulfonatothiaca lix[4]arene）]-9H2O is reported. The complex belongs to the monoclinic system, space group P2 1/c, with a = 16.703（3）, b = 17.819（4）, c = 17.357（4）A, β = 106.23（3）°, Z = 4, V = 4960.0（17）A^3, Mr = 1304.08, Dc = 1.746 g/cm^3,μ= 1.624 mm^-1, F（000） = 2688, the final R = 0.0398 and wR = 0.1132 for 7534 observed reflections with I 〉 2σ（I）. One yttrium（Ⅲ） ion is coordinated by the thiacalixarene ligand via the sulfonato group, and also ligated by an oxygen atom of a DMF molecule occupying the cavity of thiacalixarene and six aqua ligands.
