The ternary composites of graphene@SiO₂@NiO nanoflowers were fabricated by a multi-step route. Graphene oxide (GO)@SiO₂ sheets were formed by a layer of silica nanosheets coated on the surface of GO. Then, GO@SiO₂ sheets were introduced as substrates for the growth of NiO nanoflowers. The microwave absorption property of the ternary composites was studied in the frequency ranging from 2 to 18 GHz, and the effect of the thickness of the ternary composites on microwave absorption was also investigated. The results indicate that graphene@SiO₂@NiO nanoflowers composites exhibit enhanced microwave absorption compared with graphene@SiO₂. The reflection loss of graphene@SiO₂@NiO nanoflowers below −10 dB is 5 GHz (from 10 to 15 GHz) and the maximum absorption is −20.5 dB at 11.3 GHz with a thickness of 3 mm.

A report is presented on a novel non-enzymatic amperometric glucose sensor based on three-dimensional porous Cu, which was directly reduced by hydrogen from Cu(OH)₂. The surface morphology of the synthesised nanoporous Cu was characterised using field-emission scanning electron microscopy and X-ray powder diffraction. Compared with the commercial Cu nanoparticles, the nanoporous Cu modified electrode shows better catalysis to glucose, which is attributed to the special porous Cu structure providing a favourable microenvironment for glucose adsorbed in large quantity. The interesting comparative study of different cross-linking agents for the immobilisation of nanoporous Cu reports that nafion, chitosan and multi-walled carbon nanotubes (MWCNTs) can all improve the catalysis effect of porous Cu on the glucose but the MWCNT shows the best sensitive response and stability. The MWCNT plays an especially important role in stability improvement by 20% of the efficiency. Under optimal conditions, a linear dependence of the catalytic current upon glucose concentration was obtained in the range of 5.0 × 10⁻⁷–2.0 × 10⁻³ M with a detection limit of 1.0 × 10⁻⁷ M, a high sensitivity of 20.11 μA μM⁻¹, good stability and no current response from interfering species at the approximate physiological concentration level.

The design, synthesis and characterisation of biologically synthesised nanomaterials have become an area of significant interest. Presented is a report on the extracellular synthesis of gold nanoparticles using Punica granatum (Pomegranate) fruit extract as the reducing agent to synthesise Au nanoparticles. On treating aqueous chloroauric acid solutions with P. granatum fruit extract, rapid reduction of the chloroaurate ions is observed, leading to the formation of highly stable gold nanoparticles in solution. These nanoparticles showed an absorption peak at 536 nm in the UV–vis spectrum corresponding to the plasmon resonance of gold nanoparticles. Scanning electron microscopy analysis of the gold nanoparticles indicated that they ranged in size from 10 to 50 nm. The Fourier transform infrared spectroscopy spectrum confirmed the presence of main groups occurred in natural plant extract from P. granatum. The synthesised gold nanoparticles were active against Streptobacillus sp. and Escherichia coli.

A novel nanocomposite was prepared by direct mixing of titania nanoparticles (nano-TiO₂) and gold nanoparticles (nano-Au)-modified carbon nanotubes (CNTs) in a solution of chitosan. The electrochemical performance of a TiO₂/Au/CNT nanocomposite-modified electrode for hydroquinone detection was investigated. When measured at a scan rate of 50 mV s^{− 1}, the detected amount of hydroquinone at the TiO₂/Au/CNT electrode varied linearly with hydroquinone concentration, for concentrations from 1 × 10^{− 6} to 1 × 10^{− 8} M; the sensitivity was 997 617 μA(mol l^{− 1})^{− 1}, and the detection limit was 1 × 10^{− 10} M (S/N = 3). In all experiments, TiO₂/Au/CNT nanocomposites exhibited better electrochemical performance than TiO₂/CNT composites or CNTs. Enhanced current response can be attributed to the synergic effect of nano-TiO₂, nano-Au and CNTs.

An antibacterially bioinorganic composite has been synthesised by intercalating lysozymes (LZs) into layered titanates with a convenient and efficient exfoliation-restacking strategy. This composite exhibits a loose slab morphology with a thickness of 5–10 layers, and the interlayer space is ∼4.4 nm because of intercalation of enzymes. The immobilised amount of lysozymes is up to ∼68.3% in weight because of the layer-by-layer alternate and swollen structure. This composite is stable in the neutral and weakly acidic condition, and only releases <10% of lysozymes in the pH > 4 solution. The immobilised LZs exhibit excellent thermal stability, which retain their initial activities of about 70% at 70°C for about 40 min. In addition, the residual activities of the immobilised enzymes are 68% after ten recycles reuse.

Amlodipine besylate and atorvastatin calcium have been determined by the simultaneous voltammetric method at a multi-walled carbon nanotubes:graphite (MWCNTs:G) paste electrode. In comparison with a glassy carbon electrode, the prepared electrode showed an increase in the peak current because of the high electroactive surface area and excellent electronic conductivity of MWCNTs. The dependence of currents and potentials on pH were investigated for these components at the surface of the MWCNTs:G paste electrode. Differential pulse voltammetry was applied as a sensitive technique for simultaneous determination of the drugs in commercial tablets. By anodic differential pulse voltammetry, the calibration plot was linear in the range of 2.5–100 µg/ml with standard deviation between 2.7–7.1 and 1.8–8.3% for amlodipine and atorvastatin, respectively. The detection limit was 1 µg/ml at the prepared electrode in the buffered solution pH 6.

Uniform CdMoO₄ nanooctahedra with tunable sizes have been synthesised via a facile and mild microemulsion method at room temperature. The reaction between CdMoO₄ nanooctahedra and dilute hydrochloric acid was in situ monitored using microcalorimetry at 298.15 K, and microcalorimetric heat flow curves from this reaction process were obtained. Combined with an inductively coupled plasma optical emission spectrometer technique, the size effect of CdMoO₄ nanooctahedra on standard molar reaction enthalpy (Δ_r H _m ^Θ) was studied. The results indicate that the value of Δ_r H _m ^Θ decreased with decreased particle size.

A report is presented on the local anodic oxidation of graphene film prepared by chemical vapour deposition using contact mode atomic force microscopy. Raman spectroscopy was used to check the uniformity and thickness of large area graphene film. Various kinds of patterns such as lines, ribbons and further, more complex structures, such as hexagons, two-terminal bar-like devices, were written by varying the tip voltage from −6 to −12 V and the tip speed from 60 to 200 nm/s. It was found that one can easily write any kind of patterns by just manipulating the tip voltage and tip speed instead of concentrating on other factors such as controlled humidity conditions, applied force on the tip and tip current. Also, it is confirmed that with an increase in tip voltage and by slowing the tip movement during lithography, one can write very narrow and sharp patterns which are important factors for the fabrication of graphene-based electronic devices.

For the first time, CoCr₂O₄/TiO₂ nanocomposite as a novel photocatalyst with different TiO₂ contents have been prepared by the sol–gel method. The techniques of X-ray diffraction (XRD), scanning electron microscopy and transmission electron microscopy (TEM) have been employed to characterise the synthesised nanocatalysts. The XRD and TEM results indicated that CoCr₂O₄ has a cubic normal spinel structure and the particle size of CoCr₂O₄ is about 30 nm. As the first report, degradation of methylene blue and methyl orange is performed by CoCr₂O₄ and CoCr₂O₄/TiO₂ nanocomposite under ultraviolet irradiation. The results showed that the rate of degradation of dyes with CoCr₂O₄/TiO₂ is much higher compared with that of CoCr₂O₄ and TiO₂. The photocatalytic activities were carried out under varying parameters such as irradiation time, the pH of the solution, the catalyst amount and substrate concentration.

Hierarchical porous copper bulk can be fabricated through chemical dealloying of porous CuAl intermetallics under free corrosion conditions. The obtained precursor porous CuAl intermetallics and as-dealloyed hierarchical porous copper were characterised using X-ray diffraction, a field-emission scanning electron microscope and energy dispersive X-ray spectroscopy. It was found that the hierarchical porous copper can be easily prepared by this method. The dealloying solution will dramatically influence the morphology of the resultant hierarchical porous materials. As a result, trimodal porous copper composite material and bimodal porous copper can be achieved after being dealloyed in NaOH and HCl solutions, respectively. Therefore, the mechanisms of the evolution of hierarchical pores structure are also discussed.

Ternary semiconductor ZnSe_0.7Te_0.3 nanowires (NWs) are synthesised by using a thermal evaporation method, and the as-synthesised NWs have a wurtzite structure with a growth direction of [001]. The electrical measurements are carried out based on nano-field-effect transistors fabricated by individual NWs, and the electron transport characteristics reveal that the ZnSe_0.7Te_0.3 NWs have p-type conductivity with a high-mobility (μ_h ) of 0.9 cm² V⁻¹S⁻¹ and carrier concentration (n_h ) 5 × 10¹⁸ cm⁻³. Photoluminescence measurements for ZnSe_0.7Te_0.3 NWs show a dominant emission peaked at 478 nm which is the emission of free exciton.

During skeletal muscle development, correct cellular orientation is vital to generate desired longitudinal contraction for functional muscle fibres. In this reported study, submicron-imprint lithography was used to generate submicron-grooved surfaces on polystyrene plates to induce striated myotubes in vitro. Mouse muscle myoblast cells cultured on a submicron-grooved surface migrated faster in a directionally uniform fashion; in comparison, cells cultured on a flat surface grew and migrated slower in indiscriminate directions. Subsequent maturation of the myoblast cells formed along the submicron-groove surface resulted in a tandem of parallel myotubes that were both longer and greater in circumference than in the case of the flat surface. In a functional test, the co-culture submicron-groove-grown myotubes with neurotransmitter secreting cells further demonstrated contraction abilities, suggesting submicron-groove-guided growth served to enhance myotube formation while retaining striated motifs and physiological functionality for muscle tissue engineering.

Two kinds of planar-type potentiometric CO₂ gas sensors using thermal evaporated Li₃PO₄ thin film as solid electrolyte were fabricated. Alumina plates with rough and smooth surfaces were used as the substrates of the sensors. X-ray diffraction analysis, atomic force microscopy and scanning electron microscopy were used to characterise the Li₃PO₄ films. The sensing properties were investigated in the range of 500–5000 ppm CO₂ concentrations at 480°C. Both the rough substrate-based sensor (r-sensor) and the smooth substrate-based sensor (s-sensor) were sensitive to CO₂ gas and showed a good Nernst behaviour. The output electromotive force (EMF) of the s-sensor showed a more stable signal than the r-senor. The ΔEMF/decade values obtained from the r-sensor and the s-sensor were 45 and 55 mV/decade, respectively. The response and recovery time were not primarily influenced by the electrolyte film. It was found that the sensitivity of the s-sensor was closer to the theoretical value. The results revealed that the substrate surface roughness may influence the characteristics of Li₃PO₄ film and the response properties of the sensors to CO₂.

Bismuth oxybromide (BiOBr) flower-like microspheres have been successfully synthesised via a polyethylene glycol 600-assisted solvothermal process in the presence of reactable ionic liquid (IL) 1-hexadecyl-3-methylimidazolium bromide. The morphology and compositional characteristics of BiOBr were investigated by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy and diffuse reflectance spectroscopy. During the reactive process, IL not only acted as a Br source but also as a template for fabrication of BiOBr flower-like microspheres. Photocatalytic activities of flower-like microspheres were evaluated by degradation of rhodamine B under visible-light irradiation. Compared with the BiOBr nanoplates, BiOBr hollow microspheres and TiO₂ (Degussa, P25), BiOBr flower-like microspheres exhibited excellent performance in visible-light-driven photocatalysis.

Polyvinyl alcohol (PVA)/sodium dodecyl sulphate (SDS)/multi-walled carbon nanotubes (MWCNTs) composite nanofibres with various MWCNT contents (up to 10 wt%) were fabricated by electrospinning process and their microwave absorption properties were evaluated by a vector network analyser in the frequency range of 8–12 GHz (X-band) at room temperature. Scanning electron microscopy analysis of the nanofibre samples revealed that the deformation of the nanofibres increases with increasing MWCNT concentration. Very smooth surfaces of the composite electrospun nanofibres even for nanofibres with concentration of 10 wt% MWCNT have been successfully prepared because of the high stability dispersion of MWCNTs. It was observed that the absorption microwave properties improved by increasing the loading levels of MWCNTs. Finally, the PVA/SDS/MWCNT composite nanofibres sample with 10 wt% content of MWCNT has shown a reflection loss of 15 dB at a frequency of 8 GHz.

Presented is a surface nanostructuring technology for enhancing the broadband light transmittance of polymethyl methacrylate sheets. Single-side and dual-side nanostructured sheets were fabricated by a hot embossing process using nanoporous alumina moulds. The fabricated nanostructured surfaces showed appreciable broadband light transmission characteristics because of the size distribution of their nanostructures. Single-side and dual-side nanostructured sheets showed a maximum light transmittance of 96.11 and 98.74%, respectively, whereas a pristine sheet showed a light transmittance of 93.54%.

A novel thermochemical technique of depositing platinum nanoparticles (PtNPs) on a porous silicon (PS) substrate is demonstrated. Self-arranged macroporous structures, appearing as microtest tubes, are first formed on p-type, boron doped, 100 orientation silicon wafers, by the electrochemical etching method in hydrofluoric acid and N, N-dimethyl formamide solution. The macroPS substrate is then coated with PtNPs by a novel thermochemical procedure. It was observed that PtNPs deposited on the pore walls are able to arrive even at the bottom of the pores without blocking their openings. Such PtNPs-coated macroPS chips have potential biomedical applications as silicon and platinum are biocompatible.

In this reported study, hydroxyapatite (HA) nanoparticle-contained bioactive glass (BG) nanofibres with an average diameter of 500 nm have been prepared by combining a sol–gel method and an electrospinning technique. The mechanical property of the as-prepared fibres demonstrated that the HA-BG nanofibres had far higher mechanical strength than pure BG nanofibres, and the in vitro simulated body fluid immersion experiment verified that the growth rate of the hydroxycarbonate apatite nanocrystals on HA-BG nanofibre surfaces was the same with pure BG nanofibres.

SnO₂ nanocrystals with small diameters including nanorods, nanowires connected by nanorods and nanoparticles have been obtained in mixed solvents of oleic acid (OA) and ethanol. By simply adjusting the volume ratio of these solvents, the morphologies and structures of the SnO₂ crystals can be easily varied. All the products show pure tetragonal SnO₂ with a rutile structure and the obtained nanorods can be connected with each other in various ways to form nanowires. The nanocrystals with a volume ratio of OA and ethanol of 1:1 present the best photocatalytic properties which shows 100% degradation of Rhodamine B within 60 min.

The successful production, via two different oxidation processes, of metal-oxide-metal (MOM) diodes is presented. An innovative reactive ion etching and plasma assisted regrowth process has been used to provide oxides, which are in the thickness range 4.0–5.1 nm. These are thinner and physically more uniform than oxides grown in a furnace, resulting in diodes which should conduct via electron tunnelling across the MOM junction. Transmission electron microscopy analysis has been used in conjunction with time of flight secondary ion mass spectrometry analysis to verify oxide thickness and uniformity.