A novel polyoxometalate-based composite compound [Ni(phen)2][Hphen](AsW12040) (phen = 1,10-phenanthroline) I has been hydrothermally synthesized and characterized by elemental analysis, IR, TGA, ESR spectroscopy...A novel polyoxometalate-based composite compound [Ni(phen)2][Hphen](AsW12040) (phen = 1,10-phenanthroline) I has been hydrothermally synthesized and characterized by elemental analysis, IR, TGA, ESR spectroscopy and single-crystal X-ray diffraction. Each structure unit of 1 consists of one polyoxoanion AsW12O40^3-, one free phenanthroline molecule and one coordination cation [Ni(phen)2]^2+. The title compound crystallizes in the orthorhombic system, space group F212121, with a = 12.2383(7), b = 21.0884(11), c = 22.3237(12) A, V= 5761.4(5) A^3, Mr = 3520.44, Z = 4, Dc = 4.059 g/cm^3, F(000) = 6204, g(MoKα) = 24.844 mm^-1, GOF = 1.022, the final R = 0.0376 and wR = 0.0742 (I 〉 2σ(I)) for 865 parameters and 9637 observed reflections with I 〉 2σ(I).展开更多
A dimeric chromium compound has been synthesized by hydrothermal method and characterized by IR, EPR spectra and TG-DTA technique. The title compound [Cr(aea)]2(OH)2 (aea = N-(2-aminoethyl)aspartate) crystalli...A dimeric chromium compound has been synthesized by hydrothermal method and characterized by IR, EPR spectra and TG-DTA technique. The title compound [Cr(aea)]2(OH)2 (aea = N-(2-aminoethyl)aspartate) crystallizes in monoclinic, space group P21/c with a = 8.9393(10), b = 6.7198(7), c = 14.6791(16) A, β = 91.0580(10)°, V= 881.63(17) A3, Z= 2, Mr = 486.34, De= 1.832 g/cm3, F(000) = 500,μ = 1.296 mm-1, R = 0.0271 and wR = 0.0756. Single-crystal X-ray structural analysis indicates that the title compound consists of two Cr(aea) units linked by two bridging hydroxyl groups. The geometry around each chromium center is approximately octahedral and completed by two hydroxyls and a quadridentate ligand which is formed when ethylenediamine reacts with maleic acid.展开更多
The zinc-containing dust was oxidatively pretreated with calcium hypochlorite,subsequently leached with ammonia/ammonium bicarbonate solution to obtain the ammoniacal leaching solution,and zinc oxide was produced by a...The zinc-containing dust was oxidatively pretreated with calcium hypochlorite,subsequently leached with ammonia/ammonium bicarbonate solution to obtain the ammoniacal leaching solution,and zinc oxide was produced by ammonia distillation of the ammoniacal leaching solution and subsequent calcination. The elements of iron and manganese could not be detected in ammoniacal leaching solution,and the extraction rate of zinc was 98.2% in ammoniacal leaching process. The zinc oxide content in the product is 99.5%(ω),and the contents of iron and manganese in the product were 0.002 8‰ and 0.000 84‰(ω), respectively. The analyses of the valence states of iron and manganese in the zinc-containing dust with and without pretreatment were performed by chemical analysis and XPS,and the possible oxidation mechanism of the oxidative pretreatment of the dust was discussed. It is concluded that Fe 2+-oxide and Mn 2+-oxide in the dust were oxidized to Fe 3+-oxide and/or its hydrate and Mn 4+-oxide and/or its hydrate by calcium hypochlorite during the oxidative pretreatment process,respectively.展开更多
The lithium metal battery has been considered as a promising candidate for next generation batteries.However,safety concerns caused by uncontrollable lithium dendrite growth on lithium anode are severely hampering the...The lithium metal battery has been considered as a promising candidate for next generation batteries.However,safety concerns caused by uncontrollable lithium dendrite growth on lithium anode are severely hampering the commercial application.Metal-organic frameworks(MOFs)become one of the most attractive materials due to the high porosity,structural designability and tunability.With unique open channels and pores as well as functional components in MOFs,the transportation and deposition of lithium ions can be regulated,which leads to enhanced electrochemical prope rties.Various strategies for lithium metal protection are proposed in recent wo rks on applications of MOFs in lithium metal batteries.In this review,we highlight latest key approaches in this field and discuss the prospects for MOFs in advanced Li anodes.展开更多
基金This work was supported by the National Natural Science Foundation of China, Specialized Research Fund for the Doctoral Program of Higher Education, Henan Innovation Project for University Prominent Research Talents, Program for New Century Excellent Talents in Universities of Henan Province, the Foundation of Educational Department of Henan Province and Natural Science Foundation of Henan Province
文摘A novel polyoxometalate-based composite compound [Ni(phen)2][Hphen](AsW12040) (phen = 1,10-phenanthroline) I has been hydrothermally synthesized and characterized by elemental analysis, IR, TGA, ESR spectroscopy and single-crystal X-ray diffraction. Each structure unit of 1 consists of one polyoxoanion AsW12O40^3-, one free phenanthroline molecule and one coordination cation [Ni(phen)2]^2+. The title compound crystallizes in the orthorhombic system, space group F212121, with a = 12.2383(7), b = 21.0884(11), c = 22.3237(12) A, V= 5761.4(5) A^3, Mr = 3520.44, Z = 4, Dc = 4.059 g/cm^3, F(000) = 6204, g(MoKα) = 24.844 mm^-1, GOF = 1.022, the final R = 0.0376 and wR = 0.0742 (I 〉 2σ(I)) for 865 parameters and 9637 observed reflections with I 〉 2σ(I).
基金Supported by the Ministry of Education of China (No. 207068)the Natural Science Foundation of Henan Province (No. 0611023000)Henan University (06YBZR017)
文摘A dimeric chromium compound has been synthesized by hydrothermal method and characterized by IR, EPR spectra and TG-DTA technique. The title compound [Cr(aea)]2(OH)2 (aea = N-(2-aminoethyl)aspartate) crystallizes in monoclinic, space group P21/c with a = 8.9393(10), b = 6.7198(7), c = 14.6791(16) A, β = 91.0580(10)°, V= 881.63(17) A3, Z= 2, Mr = 486.34, De= 1.832 g/cm3, F(000) = 500,μ = 1.296 mm-1, R = 0.0271 and wR = 0.0756. Single-crystal X-ray structural analysis indicates that the title compound consists of two Cr(aea) units linked by two bridging hydroxyl groups. The geometry around each chromium center is approximately octahedral and completed by two hydroxyls and a quadridentate ligand which is formed when ethylenediamine reacts with maleic acid.
基金Supported by the National Basic Research Program of China(973)(No.2007CB613601)Supported by the National Natural Science Foundationof China(No.51134007)Supported by the Science&Technology Plan of Hunan Province(No.2011FJ6005)
文摘The zinc-containing dust was oxidatively pretreated with calcium hypochlorite,subsequently leached with ammonia/ammonium bicarbonate solution to obtain the ammoniacal leaching solution,and zinc oxide was produced by ammonia distillation of the ammoniacal leaching solution and subsequent calcination. The elements of iron and manganese could not be detected in ammoniacal leaching solution,and the extraction rate of zinc was 98.2% in ammoniacal leaching process. The zinc oxide content in the product is 99.5%(ω),and the contents of iron and manganese in the product were 0.002 8‰ and 0.000 84‰(ω), respectively. The analyses of the valence states of iron and manganese in the zinc-containing dust with and without pretreatment were performed by chemical analysis and XPS,and the possible oxidation mechanism of the oxidative pretreatment of the dust was discussed. It is concluded that Fe 2+-oxide and Mn 2+-oxide in the dust were oxidized to Fe 3+-oxide and/or its hydrate and Mn 4+-oxide and/or its hydrate by calcium hypochlorite during the oxidative pretreatment process,respectively.
基金financially supported by the National Natural Science Foundation of China(Nos.21625102,21471018)the Beijing Municipal Science and Technology Project(No.Z181100004418001)the Beijing Institute of Technology Research Fund Program。
文摘The lithium metal battery has been considered as a promising candidate for next generation batteries.However,safety concerns caused by uncontrollable lithium dendrite growth on lithium anode are severely hampering the commercial application.Metal-organic frameworks(MOFs)become one of the most attractive materials due to the high porosity,structural designability and tunability.With unique open channels and pores as well as functional components in MOFs,the transportation and deposition of lithium ions can be regulated,which leads to enhanced electrochemical prope rties.Various strategies for lithium metal protection are proposed in recent wo rks on applications of MOFs in lithium metal batteries.In this review,we highlight latest key approaches in this field and discuss the prospects for MOFs in advanced Li anodes.