Jianming Hong

Fabrication and photoluminescence characteristics of single crystalline In2O3 nanowires

Abstract Single crystalline In2O3 nanowires (InONWs) have been synthesized by carbothermal reduction reaction between indium oxide and active carbons at 980 °C in flowing nitrogen atmosphere. Transmission electron microscopy (TEM) image shows the formation of the nanowires at a diameter of about 20–200 nm and a length of up to hundreds of micrometers. The nanowires can emit stable and high brightness blue light at 416 and 435 nm under excitation at 260 nm. The growth process of the nanowires may be explained by vapor–solid mechanism.

Honeycomb-like Ni@C composite nanostructures: synthesis, properties and applications in the detection of glucose and the removal of heavy-metal ions

Honeycomb-like Ni@C composite nanostructures have been successfully prepared via a simple two-step solution route. Homogeneous Ni nanospheres with an average diameter of ∼100 nm were first obtained via a DMF–water mixed solvothermal route; then honeycomb-like Ni@C composite nanostructures were prepared through the hydrothermal carbonization of glucose solutions with suitable amounts of Ni nanospheres. The as-obtained products were characterized by XRD, SEM, TEM, ED, EDS and Raman spectroscopy. It was found that the as-obtained honeycomb-like Ni@C composite nanostructures showed good electrochemical properties and could be used as an electrochemical sensor for the detection of glucose molecules. Furthermore, the honeycomb-like Ni@C composite nanostructures presented good capacities for selective adsorption of Pb2+, Cd2+ and Cu2+ ions in water, and could be easily separated from water and reused.

Hierarchical ZnO micro/nanoarchitectures: hydrothermal preparation, characterization and application in the detection of hydrazine

In the present work, we report the successful preparation of hierarchical ZnO micro/nanoarchitectures in one step by a simple hydrothermal route, using Zn(CH3COO)2·2H2O, hexamethylenetetramine (HMT) and NH3·H2O (5%) as the starting materials. The product was characterized by means of powder X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM) and field emission scanning electron microscopy (SEM). The experiments showed that the morphology of ZnO could be controlled by the volume of NH3·H2O (5%). Using the hierarchical ZnO micro/nanoarchitecture, a simple amperometric sensor for the detection of hydrazine was fabricated. Cyclic voltammetry (CV) revealed that the hierarchical ZnO micro/nanoarchitecture exhibited a higher catalytic effect on hydrazine than normal, flower-like ZnO microstructures. The amperometric sensor was used in the detection of hydrazine with a detection limit of 0.25 μM over a wide linear detection range up to 200 μM, and with a high sensitivity of −15.86 μA mM−1, which is better than for other reported amperometric hydrazine sensors.

Synthesis and characterization of self-assembling (NH4)0.5V2O5 nanowires

Large-scale long (NH4)0.5V2O5 nanowires have been synthesized by rational hydrothermal treatment of ammonium metavanadate at 170 °C. Scanning electron microscope and transmission electron microscope analyses show that the nanowires have diameters of about 20–80 nm, and lengths up to 0.5 mm. Some self-assembled nanobelts are observed with a thickness of 18 nm and width of 100–200 nm. Electrical transport measurements shows that the nanowires are semiconductors with a conductivity of about 10−3 S cm−1 at room temperature. The conduction mechanism can be explained by small polaron hopping in transition metal oxides.

Co2P nanostructures constructed by nanorods: hydrothermal synthesis and applications in the removal of heavy metal ions

In this paper, we report the successful synthesis of cobalt phosphide (Co2P) nanostructures built up of nanorodsvia a simple hydrothermal route using white phosphorus (WP), sodium hypophosphite and cobalt dichloride as starting reactants in the presence of polyvinylpyrrolidone (PVP, 30 K). The as-obtained product was characterized by means of X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS), (high resolution) transmission electron microscopy (TEM/HRTEM), selected area electron diffraction (SAED) and field emission scanning electron microscopy (FESEM). It was found that sodium hypophosphite played an important role in the formation of the Co2P nanostructures. Some factors influencing the morphology of the product, including the reaction temperature, amount of sodium hypophosphite, surfactant, and so on, were investigated. The capacity of the product to remove heavy metal ions was also studied.

Hydrothermal synthesis of Ni12P5 hollow microspheres, characterization and photocatalytic degradation property

In this paper, we report the successful synthesis of Ni(12)P(5) hollow spheres via a facile hydrothermal route, employing white phosphorus (WP) and nickel nitrate as the reactants in the presence of hexamethylenetetramine (HMT) and polyethylene glycol 10000 (PEG-10000). The phase and morphology of the product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). HMT and surfactant (PEG-10000) played important roles in the formation of Ni(12)P(5) hollow microspheres. Furthermore, research also showed that the as-prepared Ni(12)P(5) hollow spheres could photocatalytically degrade some organic dyes such as Safranine T and Pyronine B under irradiation of 365 nm UV light.

Mass synthesis of dendritic Bi nanostructures by a facile electrodeposition route and influencing factors

In this paper, large dendritic Bi nanostructures were synthesized via a facile electrochemical deposition route at room temperature, employing Bi(NO3)3·5H2O as the reactant without assistance of any additive and protection of an inert atmosphere. The phase and morphology of the as-prepared product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometer (EDS), (high resolution) transmission electron microscopy (HR/TEM), selected area electron pattern (SAED) and scanning electron microscopy (SEM). Some factors influencing the formation of dendritic Bi nanostructures were investigated, including the depositing time, current, complexing agent, surfactant, the original amount and existing state of Bi(III). Experiments showed that the existence state of Bi(III) in the system, the depositing time and some complex agents could markedly affect the morphology of the final product. Also, the as-obtained product is found to have potential applications in the detection of trace metal such as Cd in water resource.

Ultrasound-assisted preparation, characterization and properties of porous Cu2O microcubes

Porous Cu2O microcubes have been successfully synthesized via an in situ ultrasound route at an ultrasound power of 90% for 3 h in the presence of polyvinylpyrrolidone (PVP), employing CuCl2·2H2O, C6H12O6·H2O, trisodium citrate and NaOH as starting reactants. The phase and morphology of the product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and field emission scanning electron microscopy (SEM). The investigations showed that the as-prepared porous Cu2O microcubes possessed good electrochemical properties and could photocatalytically degrade organic dye pyronine B under irradiation with 254 nm UV light, and could obviously restrain the propagation of E. coli.

Controllable synthesis of polyhedral YF3 microcrystals via a potassium sodium tartrate-assisted hydrothermal route

In the present paper, we reported the successful synthesis of polyhedral yttrium trifluoride (YF3) microcrystals via a simple hydrothermal route, employing yttrium oxide (Y2O3 99.99%), ammonium fluoride (NH4F) as the starting reactants and potassium sodium tartrate (C4H4O6KNa·4H2O) as the structure-directing reagent. The reaction was carried out at 150 °C for 16 h. The phase and morphology of the product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and field emission scanning electron microscopy (SEM). The research results indicated that the pH and K+ ions in the system played crucial roles in the formation of polyhedral YF3 microcrystals. Some factors influencing the morphology of YF3 crystals were investigated, including the reaction temperature, time, and the amounts of initial HNO3, NH4F and C4H4O6KNa·4H2O. A possible growth mechanism of polyhedral YF3 microcrystals is discussed.

Microwave-assisted synthesis of BaCO3 crystals with higher-order superstructures in the presence of SDS

In the present paper, barium carbonate crystals with higher-order superstructures have successfully been synthesized via a rapid microwave-assisted route in the aqueous system with sodium dodecyl sulfate (SDS), employing BaCl2·2 H2O and NaHCO3 as starting reagents. X-Ray powder diffraction (XRD) analysis showed that the product was an orthorhombic BaCO3. Scanning electron microscopy (SEM) observations showed that the higher-order superstructures were formed by the self-assembly of BaCO3 nanoflakes. Some factors, including the microwave heating power, the time, the concentration of SDS, the initial concentration of reactants, pH value of the system and kinds of surfactants, influencing the morphology of the BaCO3 crystals were systematically studied. Researches showed that SDS played a crucial role in the formation of BaCO3 superstructures.