44 research outputs found
X-shaped hollow α-FeOOH penetration twins and their conversion to α-Fe2O3 nanocrystals bound by high-index facets with enhanced photocatalytic activity
通讯作者地址: Wang, ZCNonspherical hollow nanoparticles (NHNPs) have attracted a great deal of attention in recent years due to their unique properties and many promising applications. However, compared to hollow spheres, the fabrication of NHNPs is generally much more difficult and there are only a few successful examples to date. In this work, X-shaped hollow alpha-FeOOH penetration twins were first synthesized by a facile hydrothermal reaction. X-shaped alpha-Fe2O3 hollow nanostructures with high-index {11 (2) over bar3} facets exposed were further obtained via the topotactic transformation of alpha-FeOOH precursor. To the best of our knowledge, this is the first report on the nanostructures with high-index facets as well as a hollow interior. Owing to the special hollow structure and the high-energy surface, the as-obtained alpha-Fe2O3 nanocrystals show excellent visible-light photocatalytic activity toward the degradation of RhB.State Key Development Program for Basic Research of China
2007CB935603
National Natural Science Foundation of China
5137221
Vinyl ethylene sulfite as a new additive in propylene carbonate-based electrolyte for lithium ion batteries
Vinyl ethylene sulfite (VES) is studied as a new additive in propylene carbonate (PC)-based electrolyte for lithium ion batteries. The electrochemical results show that the artificial graphite material exhibits excellent electrochemical performance in a PC-based electrolyte with the addition of the proper amount of VES. According to our spectroscopic results, VES is reduced to ROSO2Li (R=C4H6), Li2SO3 and butadiene (C4H6) through an electrochemical process which precedes the decomposition of PC. Furthermore, some of the Li2SO3 could be further reduced to Li2S and Li2O. All of these products are proven to be components of the solid electrolyte interface (SEI ) layer.National Natural Science Foundation of China (NNSFC) [29925310, 20433060, 20473068]; Ministry of Science and Technology, China [2007CB209702
Facile synthesis of hematite nanostructures with controlled hollowness and porosity and their comparative photocatalytic activities
State Key Development Program for Basic Research of China [2007CB935603]; National Natural Science Foundation of China [51372212]Hematite nanostructures with similar spindle-like shapes but different hollowness and porosities have been prepared by a facile hydrothermal method. The comparative photocatalytic activities of these samples were investigated and the results might be helpful to further understand the beneficial effects of hollow and porous structures
Mn-doped CoSe2 nanosheets as high-efficiency catalysts for the oxygen evolution reaction.
In this work, we introduce for the first time an aqueous solution method followed by a selenization step to prepare Mn-doped CoSe2 nanosheets supported on nickel foam for the oxygen evolution reaction. These findings provide us highly efficient electrocatalysts instead of noble metal catalysts for the oxygen evolution reaction
Synthesis of 2D hollow hematite microplatelets with tuneable porosity and their comparative photocatalytic activities
State Key Development Program for Basic Research of China [2007CB935603]; National Natural Science Foundation of China [51372212]alpha-Fe2O3 2D hollow microplatelets were synthesized by a facile one-pot template-free solvothermal method. The effect of synthetic parameters on the morphology and structure of the product was systematically studied. And the possible formation mechanism was proposed. Interestingly, by simply varying the concentration of NH4F, alpha-Fe2O3 hollow microstructures with similar platelet-like shapes but different porosities can be readily obtained. Their comparative photocatalytic activities were also investigated
Preparation of Co-YSZ/HAp nano-composite coating on Ti substrate by electrochemical method
Co-YSZ/HAp nano-composite coating and nano-HAp single coating were deposited on Ti substrate using the combination of electrocodeposition and electrophoretic deposition, and electrophoretic depositions, respectively. Surface and cross section morphologies of the coatings were observed by scanning electron microscope. Element distribution and crystal phase of the coatings were analyzed by energy dispersive spectrum and X-ray diffraction. The adhesive strength of the coating and Ti substrate was determined by shear strength testing. The results indicate that the adhesive strength of Co-YSZ/HAp nano-composite coating and Ti substrate is higher than that of nano-HAp single coating and Ti substrate. It shows that Co-YSZ as an interlayer reduces the mismatch of the thermal expansion coefficients between HAp and titanium and Co-YSZ/HAp nano-composite coating has better mechanical properties
Electrochemical Behavior of Vinyl Ethylene Sulfite as an Electrolyte Film-forming Additive in Lithium Ion Batteries
A film-forming additive, vinyl ethylene sulfite (VES) with both vinylene group and sulfite group, affects the electrochemical performance of carbonaceous mesophase spherules (CMS) and LiFePO4 electrode. The results indicated that a small amount of VES (5%) could be reduced prior to the propylene carbonate (PC) solvent on the surface of CMS electrode in PC-based electrolyte to form a stable solid electrolyte interphase (SEI) layer, so co-intercalation of PC and solvated lithium ions to graphite could be suppressed. Furthermore, the electrolyte of 1 mol/L LiClO4/PC+5%VES (V:V) exhibited excellent electrochemical stability in the LiFePO4 electrode
Hematite concave nanocubes and their superior catalytic activity for low temperature CO oxidation
Hematite (α-Fe2O3) concave nanocubes bound by high-index {1344} and {1238} facets were synthesized and their catalytic activity for CO oxidation were also investigated. ? 2014 the Partner Organisations
Facile synthesis and photocatalytic activity of cocoon-like hollow hematite nanostructures
State Key Development Program for Basic Research of China [2007CB935603]Hollow structures are attracting increasing attention due to their unique properties and potential applications in many fields. Despite the great successes achieved in the synthesis of hollow spheres, the preparation of nonspherical hollow structures still remains a great challenge. In this paper, we developed a facile method to prepare hematite hollow structures with cocoon-like shape. The as-prepared hematite nanococoons were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM). Such cocoon-like structures are with a uniform diameter of 18 nm, length of 90 nm, and shell thickness of 5 nm. Furthermore, the as-prepared sample exhibited high visible-light photocatalytic activity for the degradation of methyl orange due to their special hollow structure. (C) 2013 Elsevier B.V. All rights reserved
Self-assembled 3D flower-like α-Fe2O3 microstructures and their superior capability for heavy metal ion removal
Hierarchically 3D flower-like α-Fe2O3 microstructures have been synthesized through a urea-assisted hydrothermal synthetic route. The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The as-prepared product was consisted of hierarchically flow-like microstructures assembled from nanopetal subunits. The effects of the urea and NaOH on the morphology of the products were systematically studied, and a possible formation mechanism of the α-Fe2O3 microflowers was proposed based on the experimental results. These flower-like α-Fe2O3 microstructures were used as adsorbent for water treatment, and the results revealed excellent performance for heavy metal ion removal. With maximum capacities of 41.46 and 33.82 mg g-1 for As(V) and Cr(VI), respectively, such flower-like α-Fe2O 3 microstructures are expected to be an attractive adsorbent for the removal of heavy metal ions from water. ? 2013 Elsevier B.V. All rights reserved