Co-reporter:Jun Liang, Meng Li, Yao Chai, Min Luo, Li Li
Journal of Power Sources 2017 Volume 362(Volume 362) pp:
Publication Date(Web):15 September 2017
DOI:10.1016/j.jpowsour.2017.07.023
•A novel hollow CoNi2S4 nanospheres with core-shell structure is firstly fabricated.•Cost-effective and simply preparing method.•A possible inside-out evacuation and Ostwald ripening mechanism is proposed.•The hierarchical hollow nanostructure reveals excellent electrochemical properties.•This method can be applied for synthesis of other binary-metal sulfides.In this study, we report for the first time a cost-effective and general approach for the high-yield synthesis of a hierarchical core-shell and hollow structure of ternary CoNi2S4 in a triethanolamine (TEOA)-assisted hydrothermal system. It is found that a continuous increase in TEOA usages facilitates the formation and transformation of hierarchical CoNi2S4 hollow nanospheres, and the formation mechanism of the unique structure is revealed to be assembly-then-inside-out evacuation and Ostwald ripening mechanism during the sulfidation process. More importantly, when used as faradaic electrode for supercapacitors, the hierarchical hollow CoNi2S4 nanospheres display not only exceptional pseudocapacitve performance with high specific capacitance (2035 Fg−1 at 1 Ag−1) and excellent rate capability (1215 Fg−1 at 20 Ag−1), but also superior cycling stability, with only about 8.7% loss over 3000 cycles at 10 Ag−1. This work can provide some guidance for us in the structural and compositional tuning of mixed binary-metal sulfides toward many desired applications.Download high-res image (393KB)Download full-size image
Co-reporter:Jun Liang, Yao Chai, Deli Li, Meng Li, Jiaxue Lu, Li Li, Min Luo
Applied Surface Science 2017 Volume 414(Volume 414) pp:
Publication Date(Web):31 August 2017
DOI:10.1016/j.apsusc.2017.03.256
•A novel one-step solvothermal method was developed for the fabrication of hydrohausmannite.•The formation mechanism of hydrohausmannite is suggested.•The hydrohausmannite nanoplates exhibit superior pseudocapacitive properties.•This work offered an effective and reliable strategy for the preparation of hydrohausmannite.A simple and one-step solvothermal synthesis method has been developed to prepare two-dimensional (2-D) hydrohausmannite ((Mn4-2xMnx)Mn8O16-x(OH)x) nanoplates with radial length of 300 nm and thickness of about 25 nm in a binary ethanediamine/water solvent system. The formation mechanism of hydrohausmannite is suggested. As an anode material for electrochemical capacitors, the plate-shaped hydrohausmannite not only displays a high specific capacity (215 at 0.1 A g−1) and good rate capability, but also shows good stable performance along with 94% specific capacity retained after 3000 cycle tests. The method can be easily controlled and expected to be applicable for the large-scale preparation of the 2-D hydrohausmannite.
Co-reporter:Jun Liang, Ajuan Yue, Qingcheng Wang, Shuang Song and Li Li
RSC Advances 2016 vol. 6(Issue 35) pp:29497-29503
Publication Date(Web):04 Mar 2016
DOI:10.1039/C6RA03770D
Well-defined Fe3O4 nanocrystals (NCs), which exhibit excellent catalytic properties, have been synthesized in high yield via a facile hydrothermal method. Both the type of hydramine and concentration of NaOH play important roles in the formation of the Fe3O4 NCs with various morphologies. Detailed investigations indicated that the cubic and polyhedral Fe3O4 NCs can be prepared by adjusting the concentration of the triethanolamine (TEOA) in solution. The addition of increasing amounts of NaOH was found to facilitate the morphology transition from Fe3O4 cube shape to octahedron shape. The catalytic performances of these prepared samples have been investigated by reducing p-nitrophenol into p-aminophenol by an excess of N2H4 without the assistance of noble metals. The kinetics of the reduction reaction at different temperatures was also investigated to determine the activation parameters. Importantly, the obtained (100) faceted Fe3O4 nanocubes exhibits significantly higher catalytic activities than (111) faceted Fe3O4 octahedrons and bulk Fe3O4 nanoparticles, and these catalysts are stable and can be easily recycled.
Co-reporter:Li Li, Yuanyun Dou, Lifeng Wang, Min Luo and Jun Liang
RSC Advances 2014 vol. 4(Issue 49) pp:25658-25665
Publication Date(Web):02 Jun 2014
DOI:10.1039/C4RA02962C
A series of high-quality N-doped graphene (N-graphene)/Fe3O4 nanocomposites were readily obtained by a simple one-pot hydrothermal method under mild conditions. The as-prepared N-graphene/Fe3O4 hybrids were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and thermogravimetric analysis (TGA). The experimental results demonstrated that ferromagnetic Fe3O4 nanocrystals (NCs) of sub-9 nm are facilely achieved and densely anchored onto the surface of N-graphene nanosheets. As an electrode material for electrochemical capacitors, the electrochemical properties of N-graphene/Fe3O4 nanocomposites were tested, and it was interesting to find that the combination of N-graphene nanosheets with Fe3O4 NCs showed much higher specific capacitance than that of either pure N-graphene or pure Fe3O4 NCs, making them a promising electrode material for supercapacitors. Furthermore, the N-graphene hybrids also showed stable cycling performance along with 95% specific capacitance retained after 1000 cycle tests.
Co-reporter:Jun Liang, Li Li
Materials Letters 2011 Volume 65(Issue 2) pp:285-288
Publication Date(Web):31 January 2011
DOI:10.1016/j.matlet.2010.10.018
Novel α-Zn3(PO4)2·4H2O hierarchical sphere structures have been synthesized by a simple chemical method through the reaction between zinc acetate and orthophosphoric acid by using cetyltrimethylammonium bromide (CTAB) as capping reagent at room temperature. The structures and morphologies of the as-obtained products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The influences of the synthetic parameters on the morphologies of the final products were investigated. The experimental results clearly show that both the concentration of CTAB aqueous solution and the concentration of initial reagents play important roles in the formation of the α-Zn3(PO4)2·4H2O hierarchical sphere structure. Detailed proofs indicated that the process of crystal growth was dominated by a self-assembly growth mechanism.Research highlights►Quadrate-like nanosheets are synthesized. ►The quadrate-like nanosheets are assembled to cross-like crystals each other. ►The cross-like structures are obtained by a sheet-assisted process. ►Novel α-Zn3(PO4)2·4H2O hierarchical sphere consisting of nanosheets are obtained.
Co-reporter:Jun Liang;Min Luo;Caihong Yang;Junzhuo Fang
Crystal Research and Technology 2011 Volume 46( Issue 5) pp:493-496
Publication Date(Web):
DOI:10.1002/crat.201100066
Abstract
Spindle-shaped α-FeOOH nanocrystals were facilely synthesized using a poly (vinyl pyrrolidone) (PVP)-assisted route under hydrothermal conditions. The chemical compositions and morphol-ogies of the as-prepared samples were characterized in detail by X-ray power diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). The experimental results reveal that these spindle-shaped α-FeOOH nanocrystals have self-organized into assemblies with hierarchical nanostructures. The crucial roles of PVP in the hydrothermal synthesis of hierarchical α-FeOOH nanostructures were discussed. The possible formation mechanism was also suggested. Moreover, the spindle-shaped α-Fe2O3 nanocrystals could be easily obtained after calcining the α-FeOOH prepared by the PVP-assisted hydrothermal process. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Co-reporter:Jun Liang;Min Luo ;Yuan Wang
Crystal Research and Technology 2011 Volume 46( Issue 1) pp:95-98
Publication Date(Web):
DOI:10.1002/crat.201000485
Abstract
Octahedral Fe3O4microcrystals were synthesized using a triethanolamine-assisted route under hydrothermal conditions. The chemical compositions and morphologies of the as-prepared samples were characterized in detail by X-ray diffraction (XRD) and scanning electron microscopy (SEM). During the hydrothermal process for the preparation of Fe3O4 octahedra, the possible mechanism was discussed to elucidate the formation of the octahedral Fe3O4microcrystals. Triethanolamine and hydrazine hydrate play important roles in the formation of the final products. The magnetic property of sample was evaluated on a vibrating sample magnetometer (VSM) at room temperature. The values of saturation magnetization and coercivity of octahedral Fe3O4are about 103 emu/g and 157 Oe, respectively. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Co-reporter:Li Li;Jun Liang;Guangru Tian
Journal of Chemical Crystallography 2011 Volume 41( Issue 1) pp:44-47
Publication Date(Web):2011 January
DOI:10.1007/s10870-010-9834-3
Synthesis and structure of a new thiocyanato-bridged one-dimensional coordination polymer, [Cd(NCS)2(TPPO)]n (1, TPPO = triphenylphosphine oxide), have been described. The title compound crystallizes in the monoclinic P21/c space group with the unit cell parameters: a = 9.4917(4) Å, b = 22.2895(11) Å, c = 11.3300(5) Å, β = 117.433(3)°, V = 2127.49(17) Å3, and Z = 4. The single crystal X-ray diffraction revealed that the structure of 1 features thiocyanate bridges and 1D zigzag chains. The chains consist of thiocyanato-bridged five-coordinated Cd atoms. And the coordination fashion of thiocyanate group is different from the previous reported five-coordinated Cd-NCS systems.
Co-reporter:Jun Liang, ;Weiming Song;Junzhuo Fang;Min Luo ;Yanping Li
Crystal Research and Technology 2010 Volume 45( Issue 4) pp:405-408
Publication Date(Web):
DOI:10.1002/crat.200900707
Abstract
Dendrite and platelet-like α-Fe2O3 microcrystals were synthesized by the oxidation reaction of K4Fe(CN)6and NaClO3 through a simple hydrothermal method. The structures and morphologies of the as-prepared samples were characterized in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The experiment results show that NaOH played an important role in controlling the morphology of the final products. The possible mechanism was discussed to elucidate the formation of different morphologies of the α-Fe2O3 microstructures. Besides, the magnetic property of the dendrite α-Fe2O3 microstructure was characterized by a vibrating sample magnetometer (VSM). (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
