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Micro & Nano Letters, IET

Issue 5 • Date May 2012

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Displaying Results 1 - 25 of 28
  • Fabrication and characterisation of nanostructure zinc telluride by the hydrothermal method

    Page(s): 388 - 391
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (270 KB)  

    A facile route for large-scale synthesis of zinc telluride nanostructures has been achieved by a hydrothermal method. Scanning electron microscopy images showed many nanorods stuck together in the middle, composing a typical nanorod bundle. These nanorods consisted of widths in the range ~37~nm and lengths up to several micrometres. Based on a series of contrast experiments under different reaction conditions, some probable effective factors such as capping agents, reductant sorts, time and temperature were discussed. View full abstract»

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  • Silicon optoelectronic microelectrodes with integrated oxygen sensors for brain-machine interfaces

    Page(s): 392 - 396
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (235 KB)  

    In neural prosthetic systems, microelectrodes implanted in the brain record the electro-potentials elicited by specific thoughts and relay the signals to algorithms trained to translate the electrical activity into intended action. The authors describe novel elongated silicon optoelectronic neural electrodes that can record electrical signals and specific neural biomarkers. Specifically, the authors describe the integration of optical oxygen (O2) sensors with silicon neural microelectrodes. The O2 sensors are sol-gel derived xerogel thin films, that are coated on the exposed core of an optical fibre, that encapsulate O2 responsive luminophores tris(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) in their porous structures. The electrodes were inserted into the trunk region of the somatosensory cortex and lowered into the barrel field of a rat. Oxygen and action potential recordings during whisker stimulation provide support for the potential utility of the device. The proposed optoelectronic neural electrodes, which can reach depths greater than 10 mm in the brain, could help the development of intelligent and more user-friendly neural prosthesis/brain machine interfaces as well as aid in providing answers to complex brain diseases and disorders. View full abstract»

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  • Optical waveguides and polarised emission of self-assembled perylenediimide-bridged silsesquioxane microtubes

    Page(s): 397 - 401
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (334 KB)  

    A new organic waveguide material based on perylenediimide-bridged silsesquioxane (PTCDBS) microtubes is reported. The fluorescent, photoluminescence (PL) imaging and spatial-resolved PL measurements are performed on individual PTCDBS microtubes with changing the excitation position. The result demonstrates that the tube wall can act as an optical waveguide that allows the propagation of excited luminescence in the range 550-700-nm along the tube axis over several tens micrometers. In addition, the luminescence intensity exhibits an obvious dependence on the direction of the emission light polarisation with respect to the tube axis. The organic microtubes might be useful for flexible photonic microdevices, such as optical switches and interconnects, and polarised light-emitting diodes. View full abstract»

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  • Influence of current density on the interfacial bond strength of electroformed layers

    Page(s): 402 - 406
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (147 KB)  

    With the development of MEMS technology, the demand of multilayer or moveable micro-metal devices fabricated by microelectroforming is growing. The quality and life of the devices are seriously restricted by interfacial bond strength between two electroformed layers. In this Letter, a novel method to control the interfacial bond strength by adjusting the current density of microelectroforming is presented. On the basis of microelectroforming experiment, the quantitative measurement method of the interfacial bond strength by the scratch test, the effect of current density on interfacial bond strength and its mechanism are investigated. The experimental result indicates that within the range of chosen current densities, the bond strength keeps a decreasing trend along with the increase of current density, and there is a sharp decline when current density is between 0.4 and 0.6 A/dm2. The adhesion work at 0.4 A/dm2 is improved by 69.1% compared with that at 1.0%A/dm2. This phenomenon is discussed with the partial discharge theory and the relationship between current density and overpotential. The method presented in this Letter, which is simple, efficient and economical, can improve the qualified rate of microdevices and prolong their life. View full abstract»

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  • Hydrothermal synthesis of potassium/sodium titanate nanofibres and their ultraviolet properties

    Page(s): 407 - 411
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (397 KB)  

    Potassium/sodium titanate nanofibres have been successfully prepared using titanium dioxide (TiO2) microspheres as the starting material, KOH and NaOH solution as the solvent. Powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and UV-vis spectrophotometer are used to characterise various properties of the obtained nanofibres. The morphology and size of products have a close relationship with the quantity of KOH/NaOH. The nanofibres surfaces are smooth, which exhibit a wire-like morphology with a large aspect ratio. The diameter of these nanofibres falls in the range of 15-30-nm and the length ranges from several hundreds of nanometres to several micrometres. It is found that the morphologies of titanate nanofibres strongly depend on the hydrothermal conditions, in which alkali plays an important role during the whole process. The result shows that the reaction activity of NaOH with TiO2 is better than that of KOH, because the radius of K (1.33 A ) is significantly larger than that of Na (0.97 A ). The aspect ratio of the products becomes larger with the increase of the KOH concentration. When the size of the titanate nanowire samples decrease, the results show that UV vis spectra are blue-shift. These nanofibres are wideband semiconductors with a bandgap from 3.15 to 3.38 eV. This work has provided an effective method to synthesise titanate nanofibres in alkali solution, which may also be applicable to the preparation of other nanomaterials. View full abstract»

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  • Bonding, exposing and transferring technique in SU-8 and SU-8 laser micromachining combination for 3D, free-standing and multilevel microstructures

    Page(s): 412 - 414
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (229 KB)  

    This Letter reports a simple laser process to fabricate three-dimensional, free-standing and multilevel polymeric (SU-8) microstructures using a nanoseconds neodymium-doped yttrium aluminium garnet (Nd:YAG) laser. The proposed process is intended to be a complement for the bonding, exposing and transferring technique in SU-8 (BETTS) process in MEMS applications. Thanks to this technique, BETTS-laser micromachining, the fabrication of free-standing 3D SU-8 microstructures can be performed, decreasing the number of steps of the typical SU-8 process. Furthermore, it improves the aspect ratio of BETTS-based planar microstructures, and also allows the fabrication of 3D microstructures which are not possible to fabricate using BETTS, or the typical SU-8 process. To prove the viability of BETTS-laser micromachining process, several microstructures have successfully been fabricated. View full abstract»

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  • Highly photocatalytic activity for p-nitrophenol degradation with spinel-structured CuCr2O4

    Page(s): 415 - 418
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (383 KB)  

    Nano-scale copper-chromium oxide (CuCr2O4) samples were synthesised by calcining their precursors prepared via a co-precipitation procedure. The as-prepared samples were characterised by thermogravimetry and differential thermal analysis, X-ray diffraction and scanning electron microscopy technologies, respectively. The results revealed that the size of the as-synthesised sample increased by increasing the calcination temperature. The resultant samples quenched at between 400 and 500°C were composed of nanoparticles, but the ones quenched at over 550°C showed octahedral morphology in shape. The final samples were used as photocatalyst for degradation of p-nitrophenol in wastewater with assistance of H2O2 under irradiation of visible light. The photocatalytic degradation properties, including irradiation time, catalyst concentration, pH, initial concentration of the pollutant and repeatability of the catalyst were investigated, respectively. The results indicated that CuCr2O4 samples could degrade effectively p-nitrophenol. After being used ten times, the catalyst still exhibited high catalytic activity. The technology possesses potential application in treatment to wastewater containing nitrophenol pollutant. View full abstract»

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  • Two-layer radio frequency MEMS fractal capacitors in PolyMUMPS for S-band applications

    Page(s): 419 - 421
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (287 KB)  

    In this Letter, the authors fabricate for the first time MEMS fractal capacitors possessing two layers and compare their performance characteristics with the conventional parallel-plate capacitor and previously reported state-of-the-art single-layer MEMS fractal capacitors. Explicitly, a capacitor with a woven structure and another with an interleaved configuration were fabricated in the standard PolyMUMPS surface micromachining process and tested at S-band frequencies. The self-resonant frequencies of the fabricated capacitors were close to 10 GHz, which is better than that of the parallel-plate capacitor, which measured only 5.5 GHz. Further, the presented capacitors provided a higher capacitance when compared with the state-of-the-art-reported MEMS fractal capacitors created using a single layer at the expense of a lower quality factor. View full abstract»

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  • Investigation of polyacrylonitrile electrospun nanofibres morphology as a function of polymer concentration, viscosity and berry number

    Page(s): 423 - 426
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (269 KB)  

    This study focuses on using curve fitting methodology and power law equation to analyse polyacrylonitrile (PAN) nanofibres morphology synthesised by electrospinning. The effects of polymer solution properties (i.e. polymer concentration, viscosity and Berry number) on electrospinnability of the PAN/DMF (N,N-dimethylformamide) solutions are investigated. For the polymer electrospun from concentrated solution (3.5<;Be<;7.5), the nanofibres form without beads. The relationship between solution viscosity and its concentration is in the form: <;<;0.0205C4.16, the relation between the diameter of electrospun the PAN nanofibres and solution concentration is in the form: d=0.0326C3.45, and the relationship between the nanofibres diameter and solution viscosity is in the form: d=0.834=0.827. View full abstract»

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  • Study of hydrophobic SiO2 films on enamel substrate via sol-gel process

    Page(s): 427 - 429
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (194 KB)  

    In this Letter, sol-gel was used to prepare hydrophobic films on the enamel substrate. Using tetraethoxysilane (TEOS) as the precursor, which was combined with dimethyldichlorosilane (DDS), films with SiO2 nanoparticles were coated on the enamel substrate, which make the droplets contact angle increase to over 110°. Fourier transform infrared spectroscopy and field emission scanning electron microscope were used to determine the elements and structure of hydrophobic film on the enamel substrate. It was found that SiO2 nanoparticles were beneficial to increase surface roughness while -CH3 incorporated could decrease the film surface energy. The high surface roughness and low surface energy make it a hydrophobic performance which brings a new value to the application of enamel materials. View full abstract»

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  • Cardiovascular stent design and wall shear stress distribution in coronary stented arteries

    Page(s): 430 - 433
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (487 KB)  

    The stent is a major breakthrough in the treatment of coronary artery diseases. The permanent vascular implant of a stent, however, changes the intra-stent blood flow haemodynamics. There is a growing consensus that the stent implant may change the artery wall shear stress distribution and hence trigger the restenosis process. Computational fluid dynamics (CFD) has been widely used to analyse haemodynamics in stented arteries. In this Letter, CFD models were developed to investigate the effects of stent design pattern and strut geometry, respectively, on the wall shear stress distribution in coronary stented arteries. Assessment of the potential restenosis risk was primarily based on the wall shear stress distribution. Results show that the stent design pattern alone does not have a significant impact on the stent haemodynamic behaviour. Wall shear stress is very sensitive to strut thickness, while varying the strut width or crown radius has very little effect. The proposed methodology and findings will provide great insight for future optimisation of stent design to reduce the risk of restenosis. View full abstract»

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  • Uncooled bimaterial cantilever for infrared detection based on resonant frequency tracking

    Page(s): 434 - 438
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (389 KB)  

    A novel method of detecting infrared (IR) radiation by tracking resonant frequency of bimaterial resonant sensors is presented. A capacitive bimaterial resonant sensor (BRS) array consisting of 6×6 cells is fabricated by surface sacrificial layer process. The BRSs are packaged and tested not only by optical but also by electrical method. The results indicate that the BRSs exhibit a monotonic frequency response, which is in correspondence with the theoretical prediction by finite element method. The resonant frequency responsivity of the BRS is better than 363×Hz×K by electrical measurement. View full abstract»

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  • Synthesis of LiMnO2 porous microsphere and its electrochemical behaviour as cathode material in lithium-ion batteries

    Page(s): 439 - 442
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (312 KB)  

    Orthorhombic LiMnO2 porous microspheres with the pore size of 200-500 nm were synthesised by Mn2O3 precursor and LiOH·H2O at 750°C for 5 h. Field-emitting scanning electron microscope images show the obtained products basically preserve the initial morphology of Mn2O3 precursor. The electrochemical tests of the as-obtained LiMnO2 presented the maximum discharge capacity of 163 mAh/g at the 11th cycle, and remained above 143 mAh/g after 30 cycles at a current density of 30 mA/g, corresponding to a capacity fading of 12.1%. For comparative purpose, the LiMnO2 nanoparticles prepared with the Li2CO3 substituted for LiOH·H2O as the lithium source were studied, which showed their maximum discharge capacity was only 153 mAh/g, together with a capacity of 136 mAh/g after 30 cycles at the same current density. View full abstract»

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  • Dimensional control of titanium dioxide nanotube arrays with hydrogen peroxide content for high photoelectrochemical water splitting performance

    Page(s): 443 - 447
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (321 KB)  

    Adding hydrogen peroxide (H2O2) for the fast formation of titanium dioxide (TiO2) nanotube arrays produce smooth and clean TiO2 nanotubes without bundling and cracking problems. The nanotube formation rate accelerated after the periodical addition of H2O2 at different intervals. Adding H2O2 at 10 min intervals formed longer nanotubes (13 m) with larger pore diameters (140 nm). These novel TiO2 nanotubes exhibited optimal photocurrent density (1.8 mA/cm2) and 3.8% photoconversion efficiency because of high crystallinity with numerous oxygen vacancies in the large pore diameters allowed for better light absorption and good interaction between the electrolytes and TiO2 nanotubes. View full abstract»

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  • Preparation of Al-Fe/TiB2 nanocomposite powder by ball milling and subsequent heat treatment

    Page(s): 448 - 452
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (250 KB)  

    In this study, mechanical alloying (MA) was used to synthesise Al-Fe/TiB2 nanocomposites using aluminium, ferrotitanium and acid boric as raw materials. The powders were mixed and subjected to MA in an attritor ball mill under argon (Ar) atmosphere. Then, the milled powders were heat-treated under Ar atmosphere. The phase transformation, microstructure and morphology of MA powders were investigated by X-ray diffraction and scanning electron microscopy. The results showed that the heat-treated powders lead to the in situ formation of nanosized TiB2 particles in the Al matrix with an average grain size of 45 nm. It was also found that after heat-treating, TiB2 phase and other intermetallics such as Al13Fe4 and Al3Ti have been formed. View full abstract»

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  • Luminescence in Eu2+-activated microcrystalline pyrophosphor

    Page(s): 453 - 455
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (221 KB)  

    A microcrystalline Sr2P207:Eu2+ pyrophosphate-based phosphor was prepared by the modified solid-state diffusion. The crystalline phases were recognised using X-ray diffraction and surface morphology was studied by scanning electron microscope. Photoluminescence properties were investigated under ultraviolet-ray excitation. The Sr2P207:Eu2+ exhibits unique colour: a blue band centred at 430 nm originating from Eu2+ when excited at 328 nm, Commission Internationale de l Eclairage chromaticity coordinate values are calculated from emission spectra of Sr2P207:Eu2+ for the prepared sample. The results show Sr2P207 is a promising microcrystalline host lattice for the solid-state lighting. View full abstract»

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  • Fabrication of superhydrophobic surfaces with high adhesive forces towards water on steel substrates

    Page(s): 456 - 459
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (313 KB)  

    The present Letter reports a simple and effective two-steps immersion method to fabricate superhydrphobic surfaces with high adhesive forces towards water on steel substrates. The steel plates were firstly immersed in the aqueous CuSO4 solution for 20 s, and then immersed in the stearic acid ethanol solution for 24 h. The sample surfaces were characterised by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectrophotometry, X-ray diffraction and optical contact angle measurements. The results show that, after two-steps immersion processes, the cupric stearate microspheres with binary micro/nanometre-scale rough structures are formed on the steel surfaces. The as-prepared steel surfaces exhibit a good high adhesive superhydrophobicity with a 166.3 water contact angle and no rolling angle. The high adhesive superhydrophobic surfaces on steel substrates have a good potential application in no loss liquid transportation. View full abstract»

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  • Photoluminescent and nonlinear optical properties of aqueous synthesised Cd0.6Zn0.40.4Te nanocrystals in different temperatures

    Page(s): 460 - 463
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (198 KB)  

    In this Letter, Cd0.6Zn0.4Te nanocrystals were synthesised in aqueous solution, in presence of short-chain thiol thioglycolic acid (TGA) as stabiliser. The samples have been characterised by X-ray diffraction, which confirmed that the alloyed nanocrystals were formed and crystal structure is FCC. The synthesis temperature effect on linear optical properties of the nanocrystals has been studied by room temperature UV-vis absorption and photoluminescence (PL) spectroscopy. It can be observed as a red shift in emission and absorption peaks by increasing the synthesis temperature. All obtained samples display a narrow PL and sharp absorption spectra because of the monodispersed distribution. Nonlinear indices of Cd0.6Zn0.4Te nanocrystals were defined by the z-scan technique using continuum wave (CW) He-Ne laser (--632.8-nm). The results reveal that these nanoparticles exhibit strong nonlinear optical (NLO) effect such as self-defocusing and two-photon absorption. The z-scan results show that by increasing the synthesis temperature, the nonlinear coefficients were reduced. View full abstract»

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  • Facile microwave-assisted synthesis of PbS nanotubes

    Page(s): 464 - 466
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (255 KB)  

    Nanoparticle-assembled tube-like PbS nanostructures were successfully fabricated in the aqueous solution of Pb(NO3)2, NH2NHCSNH2 and NaOH through a green microwave-assisted chemical synthesis route without using any surfactants. The products were characterised by X-ray diffraction, energy dispersive X-ray spectrometry, field-emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy and selected area electron diffraction. The prepared PbS nanotubes are composed of nanoparticles with diameters of 20-40-nm. The outer diameter, the thickness and the length of the PbS nanotubes can be identified as 200-400-nm, 60-100-nm and 2-6--m, respectively. The influencing factors, such as alkaline source, sulphur source and lead source, were investigated. The experimental results revealed that the introduction of NaOH into the reaction system of Pb(NO3)2 and NH2NHCSNH2 is essential for the growth of tube-like PbS nanostructures. View full abstract»

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  • Nano-hydroxyapatite/fibrin glue/recombinant human osteogenic protein-1 artificial bone for repair of bone defect in an animal model

    Page(s): 467 - 471
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (200 KB)  

    Nano-hydroxyapatite (nano-HA), with similar components of human bone tissues and good biomechanical properties, is considered as the most promising bioactive material. Its application, however, is still limited because of its lack of bone induction effect. To assess the ability of polypro nano-HA/fibrin glue/recombination human osteogenic protein-1 (nano-HA/FG/rhOP-1) for bone defect reconstruction. After the unilateral radius bone defect was established at the 45 New Zealand white rabbits, they were randomly divided into the nano-HA/FG/rhOP-1 (Group A), nano-HA/FG (Group B) and control groups (Group C; without repair), each with 15 rabbits. The ability of bone defect repair was evaluated by gross observation, X-ray radiography, scanning electronic microscope, radionuclide bone imaging and biomechanical analysis at 4, 8 and 12 weeks after repair. The radio graphically score, bone formation, radionuclide intake ratio and biomechanical strength were higher in the nano-HA/FG/rhOP-1 group than the nano-HA/FG and control groups at 4, 8 and 12 weeks (P<;0.05). There were no bone connection at the defect site and the bone defect was reconstructed in the control group. It is indicated that the nano-HA/FG/rhOP-1 artificial bone has good osteoconductibility and is a promising material for repair of bone defect. View full abstract»

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  • Sintering behaviour and electrical properties of gadolinia-doped ceria modified by addition of silicon oxide and titanium oxide

    Page(s): 472 - 475
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (236 KB)  

    The small amount (0.25 wt. ) of SiOX and TiOX as sintering aids was added to gadolinia-doped ceria (GDC) powder for densifying solid electrolytes by sol-gel method. Material characteristics of the prepared and calcined electrolytes were identified by X-ray diffraction for crystalline structures, Brunauer-Emmett-Teller measurements for surface, area and scanning electron microscopy for surface morphology and microstructures. The route process of doping SiOX and TiOX as sintering aid in GDC electrolytes not only suppresses crystallite growth to form the ultrafine particle, but also lowers the sintering temperature for the densification process of bulk electrolyte by active sintering or liquid phase sintering. Additionally, doping a small amount of SiOX and TiOX also increases the relative density of the bulk electrolyte and the total conductivity. Material produced in this way could be recommended as solid electrolyte layers for solid oxide fuel cell systems to be densifying the compared with the well-known yttria-stabilised zirconia. View full abstract»

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  • Facile synthesis of pyroaurite-type Co-Fe layered double hydroxides for anionic dye adsorbents

    Page(s): 476 - 479
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (406 KB)  

    Layered double hydroxides (LDHs) are characterised by the two-dimensional lamellar-stacking structure through weak interactions and have attracted great interest because of their extensive applications as ion-exchanging carriers, adsorbents, precursors of metal oxide catalysts etc. In this work, a facile hydrothermal route has been developed to synthesise novel pyroaurite-type Co-Fe LDHs, with a formula of CoII5.84FeIII2.16(OH)16(CO3)1.08 · 0.32H2O, using lysine (Lys) molecules as the directing reagent. Co-Fe LDH nanostructures obtained were characterised by means of a scanning electron microscope, transmission electron microscopy, X-ray diffraction, fourier transform infrared and thermogravimetric analysis. Furthermore, the adsorption performance of Co-Fe LDH nanostructures, both the flower-like and octahedral structure, was assessed using different dyes as the model. The results demonstrate that pyroaurite-type Co-Fe LDHs exhibit excellent adsorption performance on anionic dyes (such as Methyl orange, Congo red and Acid blue 80) in aqueous solution, indicating great potential for the removal of anionic organic contaminants from the industrial effluents. View full abstract»

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  • Synthesis and electrocatalytic properties for p-nitrophenol deduction of nano-scaled M3O4 (M = Fe, Co) products with different shapes

    Page(s): 480 - 484
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (444 KB)  

    Spinel-structured M3O4 (M=Fe, Co) samples with different shapes were synthesised mainly via a hydrothermal procedure. All Fe3O4 samples were prepared using a one-step process; however, all Co3O4 samples were synthesised via two-step paths, namely their precursors were prepared first then the resultant oxide products were obtained by calcining their precursors at a certain temperature. The samples were characterised by thermogravimetric analysis, X-ray diffraction, transmission electron microscopy, high-resolution electron microscopy and field-emission scanning electron microscopy measurements, respectively. The results showed that plate-, particle- and sphere-like Fe3O4 and sheet-, particle- and tube-like Co3O4 samples were obtained successfully. The electrocatalytic properties of the samples modified on a glassy carbon electrode were investigated, and the results indicated that Fe3O4 and Co3O4 samples with different shapes exhibited different enhanced electrocatalytic activity for p-nitrophenol reduction, and Fe3O4 and Co3O4 nanoparticles all showed the highest elctrocatalytic activity. View full abstract»

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  • Facile approach to ZnO nanorods by directly etching zinc substrate

    Page(s): 485 - 488
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (306 KB)  

    The growth of ZnO nanorods by directly etching Zn foil through a low-temperature aqueous method has been demonstrated. The as-obtained ZnO nanorod possesses a single crystalline structure. The morphologies of ZnO nanostructures are sensitive to a series of growth parameters. Room-temperature photoluminescence property of the as-synthesised ZnO nanorods shows a strong ultraviolet emission peak at 379 nm. The present work demonstrates the feasibility of the growth of semiconductor nanorods by directly etching the substrate. View full abstract»

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  • Facile synthesis and antineoplastic activity of bovine serum albumin-conjugated Ag/Ca phosphate nanocomposites

    Page(s): 489 - 491
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (154 KB)  

    A facile method was designed to fabricate bovine serum albumin (BSA)-conjugated Ag/Ca phosphate nanocomposites (Ag/CaPNCs). High-resolution transmission electron microscopy and scanning electron microscope indicated that Ag/CaPNCs with about 1000 nm in diameter were composed of smaller nanoparticles and had dispersity. Fourier transform infrared spectrograph, thermogravimetry- differential scanning calorimetry and atomic absorption spectroscopy clearly displayed that the content of BSA, Ag and Ca reached 26.7, 21.2 and 46.0%, respectively. The metabolic viability assay indicated that Ag/CaPNCs could inhibit the metabolism of PC 12 cells in a dose-dependent manner, with 64.8 ppm of the half maximal inhibitory concentration (IC50). Consequently, the present study suggested that Ag/CaPNCs had potential as cytostatic agents. View full abstract»

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Aims & Scope

Micro & Nano Letters offers express publication of short research papers presenting research conducted at the forefront of micro- and nanoscale science, engineering and technology, with at least one dimension ranging from a few tens of micrometres to a few nanometres.

Full Aims & Scope

Meet Our Editors

Editors-in-Chief
Professor Gwo-Bin Vincent Lee
National Tsing-Hua University, Taiwan

Professor Peter Dobson
University of Oxford, UK