A facile EDTA （ethylene diamine tetraacetic acid） complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction （XRD）, sc...A facile EDTA （ethylene diamine tetraacetic acid） complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and Fourier transform infrared spectroscopy （FT-IR）. The results show that a homogeneous transparent gel can be obtained with EDTA as the organic complexing reagent under the pH value of 3.0. Further thermal decomposition of the as-synthesized transparent gel by increasing the temperature up to 600℃ for 3 h results in the formation of La2Mo2O9 nanoparticles with a crystal size of about 30 nm. Moreover, the nanoparticles tend to form micrometer-sized aggregates with a three-dimensional network structure, which shows promising applications in solid oxide fuel cells （SOFC）, catalysts and so on.展开更多
The potassium triaqua(ethylenediamine-tetraacetate)gadolinium (Ⅲ) pentahydrate, K[Gd(Edta)(H2O)3]5H2O, has been synthesized and structurally characterized. It crystallizes in orthorhombic, space group Fdd2 with a = 1...The potassium triaqua(ethylenediamine-tetraacetate)gadolinium (Ⅲ) pentahydrate, K[Gd(Edta)(H2O)3]5H2O, has been synthesized and structurally characterized. It crystallizes in orthorhombic, space group Fdd2 with a = 19.8851(6), b = 36.078(1), c = 12.2306(4) , V = 8774.3(5) 3, Z = 16, Dc = 1.904 g/cm3, Mr = 628.69, m = 3.290 mm-1, F(000) = 5008, the final R = 0.0293 and wR = 0.0763 for 3314 observed reflections with I > 2s(I). The Gd atom in the title compound is nine-coordinate through four O atoms and two N atoms in ethylenedi- amine-tetraacetate, and three O atoms of water.展开更多
Developing nonprecious carbon electrocatalysts as alternatives to platinum for cathodic oxygen reduction reaction in fuel cells is of signifi- cance. Herein, an efficient precursor-controlled synthesis strategy based ...Developing nonprecious carbon electrocatalysts as alternatives to platinum for cathodic oxygen reduction reaction in fuel cells is of signifi- cance. Herein, an efficient precursor-controlled synthesis strategy based on extremely rapid nucleation and deposition process assisted by the liquid nitrogen freeze drying method is explored to anchor cheap iron-EDTA complex evenly dispersed on graphene to realize mJcrostructural homogeneity of the derived Fe-N-C oxygen reduction electrocatalyst. The prepared electrocatatyst possesses excellent performance including high activity with more positive onset and half-wave potential, a long-term stability, and anti-poisoning effect compared to commercial Pt/C. The activity correlates well with the unique sheet-shaped morphology, high surface area, hierarchical porous structure, and the introduction of Fe-Nx/C species. Especially, both the assembled practical alkaline and acid fuel cells based on the synthesized cathode catalysts reveal excellent performance with high open-circuit voltage and power density.展开更多
基金the Opening Subject of the State Key Laboratory of Powder Metallurgy of China (Nos. 200506123105A and 20070620090631B14)
文摘A facile EDTA （ethylene diamine tetraacetic acid） complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and Fourier transform infrared spectroscopy （FT-IR）. The results show that a homogeneous transparent gel can be obtained with EDTA as the organic complexing reagent under the pH value of 3.0. Further thermal decomposition of the as-synthesized transparent gel by increasing the temperature up to 600℃ for 3 h results in the formation of La2Mo2O9 nanoparticles with a crystal size of about 30 nm. Moreover, the nanoparticles tend to form micrometer-sized aggregates with a three-dimensional network structure, which shows promising applications in solid oxide fuel cells （SOFC）, catalysts and so on.
基金This work was supported by the National Natural Science Foundation of China(20001007,20131020) and Natural Science Foundation of CAS (KJCX2-H3) and Fujian Province (2000F006)
文摘The potassium triaqua(ethylenediamine-tetraacetate)gadolinium (Ⅲ) pentahydrate, K[Gd(Edta)(H2O)3]5H2O, has been synthesized and structurally characterized. It crystallizes in orthorhombic, space group Fdd2 with a = 19.8851(6), b = 36.078(1), c = 12.2306(4) , V = 8774.3(5) 3, Z = 16, Dc = 1.904 g/cm3, Mr = 628.69, m = 3.290 mm-1, F(000) = 5008, the final R = 0.0293 and wR = 0.0763 for 3314 observed reflections with I > 2s(I). The Gd atom in the title compound is nine-coordinate through four O atoms and two N atoms in ethylenedi- amine-tetraacetate, and three O atoms of water.
基金This work was financially supported by Ministry of Science and Technology of China （Nos. 2026YFB0200203 and 2017YFA0206704）, National Program on Key Basic Research Project of China （No. 2014CB932300）, Strategic Priority Research Program of the Chinese Academy of Sciences （No. XDA09010404）, Technology and Industry for National Defense of China （No. JCKY2026130B010）,and National Natural Science Foundation of China （Nos. 51771177, 21422108 and 51472232）.
文摘Developing nonprecious carbon electrocatalysts as alternatives to platinum for cathodic oxygen reduction reaction in fuel cells is of signifi- cance. Herein, an efficient precursor-controlled synthesis strategy based on extremely rapid nucleation and deposition process assisted by the liquid nitrogen freeze drying method is explored to anchor cheap iron-EDTA complex evenly dispersed on graphene to realize mJcrostructural homogeneity of the derived Fe-N-C oxygen reduction electrocatalyst. The prepared electrocatatyst possesses excellent performance including high activity with more positive onset and half-wave potential, a long-term stability, and anti-poisoning effect compared to commercial Pt/C. The activity correlates well with the unique sheet-shaped morphology, high surface area, hierarchical porous structure, and the introduction of Fe-Nx/C species. Especially, both the assembled practical alkaline and acid fuel cells based on the synthesized cathode catalysts reveal excellent performance with high open-circuit voltage and power density.
