A low-cost, highly reflective, liquid organic nanostructure silver conductor with superior conductivity, using back contact reflectors in amorphous silicon (a-Si) single-junction superstrate configuration thin-film solar cells produced using a non-vacuum screen printing process is proposed. The conductive paste is composed of Ag nanowires (Ag NWs) mixed with an Ag nanostructure (Ag NS) sheet. The paste is referred to as ‘Ag NWS’. A comparison of silver conductor samples with vacuum-system-sputtered silver samples indicated that the short-circuit current density (J _sc) and the open-circuit voltage (V _oc) of Ag NWS conductor cells exceeded 0.22 mA/cm² and 66 mV, respectively. The Ag NWS conductor with back contact reflectors in solar cells was analysed using external quantum efficiency measurements to effectively enhance light-trapping ability in a long wavelength region (580–700 nm). The cells constructed using the optimised Ag NWS demonstrated an increase of approximately 6.1% in power conversion efficiency under AM 1.5 illumination. These results indicated that the Ag NWS conductor back contact reflector layer is a suitable candidate for high-performance a-Si thin-film solar cells.

The synthesis reaction of potassium dicyanoaurate-hexacyanoferrate electrolyte and the pertinence of this electrolyte for gold nanowire synthesis are reported. Gold nanowires were synthesised in anodic aluminium oxide (AAO) nanopores using an improved design of the electrochemical cell. AAO templates with thick gold layers were placed on the surface of the electrolyte, thus the ends of the nanopores were opened, allowing the electrolyte to freely diffuse into the nanopores, extruding gases. The presented procedure simplifies the preparation before nanowire synthesis: AAO templates before synthesis do not need to degas and isolate themselves from contact with the electrolyte by a parafilm or a non-conductive adhesive. A considerably faster nanowire growth in the given conditions in the case of a semi-immersed AAO template when compared with the complete immersion method is reported. For comparison with literature data, gold nanowires were synthesised by the classical electrochemical cell using potassium dicyanoaurate-citrate electrolyte. Long, smooth and high purity nanowires were obtained using semi-immersed templates.

Silver (Ag) nanoparticles with a pure face-centred cubic phase were grown on indium tin oxide (ITO) substrate via the electrodeposition method. The products were characterised by scanning electron microscopy, energy-dispersive X-ray analysis and X-ray diffraction. Ag nanoparticles deposited on the ITO substrate were first used as an electrode for the electrochemical analysis of lead ions. A linear response was observed for Pb²⁺ in the range of 0.1–8 µM. The linear regression equation was I = 0.129 + 0.368C (unit of C is μM) and the correlation coefficient was 0.9993. The detection limit was 70 nM Pb²⁺ (S/N = 3). The results open new possibilities for the fabrication of novel electrodes for the construction of simple, low-cost and reliable electrochemical sensors for the quantification of trace levels of Pb²⁺.

A versatile electroless copper plating method for the fabrication of Cu-coated glass microspheres was successfully developed using hydrazine hydrate as the reducing reagent. To obtain the best morphology and electrical conductivity of Cu-coated glass microspheres, some main synthetic factors including the concentration of copper salt, volume of aqueous ammonia and bath temperature were investigated in detail. The crystal structure and shape of the copper layer were characterised by X-ray diffraction and scanning electron microscope techniques. The result showed that the glass microspheres with a uniform copper coating exhibited a face-centred cubic crystal structure and an excellent volume resistivity (ρ_ν ) of 4.28 × 10⁻⁴ Ω·cm. This method could also be extended for the fabrication of Ag- and Co-coated glass microspheres with superior conductivity.

Ultra-lightweight heat resisting poly(methyl methacrylate) (PMMA)/silica fume microspheres were successfully prepared via in-situ suspension polymerisation. Scanning electron microscopy indicated that PMMA/silica fume composite microspheres had good sphericity and the silica fume particles were evenly dispersed in microspheres and formed lots of macroporous material. Furthermore, density analysis illustrated that the density of composites was about 1.06–1.24 g/cm³ with good suitability for water carrying. Thermal stability of the PMMA/silica fume composite particles was significantly better than pure for PMMA. Therefore, PMMA/silica fume composite microspheres possess an entirely feasible application in oil exploitation as ultra-lightweight proppants.

A report is presented on the antibacterial activity of platinum and palladium nanoparticles (NPs) prepared by direct sputtering into glycerol. Prepared platinum faceted NPs (n = 500) with the diameter of (1.7 ± 0.3) nm and palladium faceted NPs (n = 500) with the diameter of (2.4 ± 0.4) nm were investigated. The size and shape of NPs were studied by transmission electron microscopy. Moreover, the size and its distribution were studied by dynamic light scattering. The concentration of metal NPs in prepared solutions was determined by atomic absorption spectroscopy. The optical properties of aqueous NP solutions were studied by UV–vis absorption spectroscopy. Antibacterial properties were tested against two common pollutants (E. coli DBM 3138, a Gram-negative bacteria and S. epidermidis DBM 3179, a Gram-positive bacteria). Owing to the increasing resistance of bacteria strains to common antibiotics, this study may provide an alternative way to fight these pollutants.

γ-Fe₂O₃ nanoparticles coated with a layer of FeCl₃·6H₂O were prepared by chemically induced transition in FeCl₂ solution. NaOH was added to the reaction solution, to investigate the effect of alkalinity on the resulting particles. Vibrating sample magnetometry, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy were used to characterise the products. Additional NaOH stimulated the epitaxial growth of γ-Fe₂O₃ on the γ-Fe₂O₃ crystallites and more FeCl₃·6H₂O adsorbed on γ-Fe₂O₃. Under the experimental conditions, the increase in γ-Fe₂O₃ content was larger than that of FeCl₃·6H₂O, at ≤0.7 M NaOH. At >0.7 M NaOH, the increase in γ-Fe₂O₃ content was less than that of FeCl₃·6H₂O. The non-monotonic variation of the FeCl₃·6H₂O/γ-Fe₂O₃ ratio was consistent with this result, and was consistent with the variation in apparent specific magnetisation with increasing NaOH concentration.

Iron oxide-filled multi-walled carbon nanotubes (Fe₂O₃@MWCNTs) composite particles were produced by a mild and superior physical absorption method using molten Fe(NO₃)₃·9H₂O as the precursor. Characterisation of Fe₂O₃@MWCNTs composite particles was performed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and thermogravimetry-differential scanning calorimetry. The results showed a large number of hematite phase Fe₂O₃ were uniformly filled in the MWCNTs, and the mass fraction of Fe₂O₃ was about 25.8 wt%. Furthermore, in the presence of 10 wt% Fe₂O₃@MWCNTs composite particles, the peak temperature of the high-temperature decomposition of ammonium perchlorate (AP) decreased by 116°C, the peak of the low-temperature decomposition disappeared and the amount of AP heat released was increased about 200 kJ/mol.

During the recent past, carbon nanotubes (CNTs) have rapidly gained importance in an intensely growing researched area of interconnects. For various reasons, bundled CNTs are often preferred over single-walled CNTs (SWCNTs) or multi-walled CNTs (MWCNTs). However, during fabrication, it is difficult to control the growth of a densely packed bundle having SWCNTs with uniform diameters or MWCNTs with an identical number of shells. Therefore, a realistic CNT bundle is in fact a mixed CNT bundle (MCB) that consists of SWCNTs and MWCNTs. In light of these facts, an analytical model of a MCB that follows the random distribution of CNTs in a bundle is introduced. Depending on the probability of distribution of CNTs having different diameters, a compact multi-conductor transmission line (MTL) and a simplified equivalent single conductor (ESC) model are presented. Encouragingly, the simplified ESC model exhibits an average error of only 2.44% at different interconnect lengths compared with the delay obtained through the MTL approach. Mean diameter and tube density of the MCB are mapped to the ESC model to analyse the propagation delay, power dissipation and crosstalk. Irrespective of interconnect lengths, it is observed that the performances are significantly improved for higher tube density in a MCB.

Uniform octahedral zinc tetraphenylporphyrin (ZnTPP) microcrystals were obtained in a large scale by a facile, fast and surfactant-free process at room temperature. The effects of synthetic parameters such as solvent and concentration on the formation and morphology of ZnTPP were investigated. Furthermore, by varying the reaction time, both the morphology and the size of the ZnTPP microcrystals can be controlled.

Protuberant mounds and micro-nanoholes are prepared on the GaAs surface under Langmuir evaporation. It is demonstrated that mounds are oxidised Ga-rich droplets with minute As. Through analysis of the experimental conditions of samples forming holes and mounds, the correlation between the two phenomena is presented. It is concluded that annealing time is the key factor in controlling the size of mounds and holes and that the annealing temperature is one predominant factor in deciding the evolution direction of the structure on GaAs—forming holes or protuberant mounds. The tuning over the GaAs surface morphology will be potentially applied in the preparation of quantum dots used for optical and electronic devices.

Graphene oxide was prepared by a modified Hummers method in a Teflon-lined autoclave and then reduced by two different approaches. Alkaline reduction by sodium hydroxide as the control and synergetic reduction which combined sodium hydroxide and microwave irritation were conducted. The products were characterised by transmission electron microscopy, X-ray diffraction, thermo-gravimetric analysis, Fourier transform infrared spectroscopy and by atomic force microscopy. Results showed that the synergetic method possessed higher efficiency. Moreover, the as-prepared samples were monolayers (about 0.8 nm) and could decrease the solubility of ethyl cellulose in ethanol.

In this reported work, the free axial vibration response of carbon nanotubes (CNTs) with arbitrary boundary conditions is studied based on the non-local elasticity theory. Using Fourier sine series together with Stokes’transformation, the general frequency determinant of CNTs is obtained. The main advantage of this method is its capability of dealing with rigid or restrained boundary conditions. Comparisons between the results of the presented method and previous works in the literature have been performed. Good agreement is obtained when enough terms are included in the Fourier series expansion. The effects of spring parameters on the vibration frequencies are discussed in detail. The proposed analytical method can be utilised for dynamic analyses of nanorods (CNTs) with arbitrary boundary conditions.

Zinc silicate (Zn₂SiO₄) nanorods with diameters of 90–100 nm and lengths of up to 600–700 nm have been successfully prepared by a simple hydrothermal route without the assistance of any templates or surfactants. The characterisations of the products were carried out by X-ray diffraction (XRD), field-emission scanning electron microscopy and transmission electron microscopy technology. On the basis of XRD and scanning electron microscopy analyses of the products at different reaction time periods, an Ostwald ripening mechanism is proposed to elucidate the formation mechanism of the nanorod structure. The electrochemical performance of the as-prepared Zn₂SiO₄ nanorods was investigated by a galvanostatic charge–discharge method. The results have shown that the Zn₂SiO₄ nanorods exhibited a higher discharge capacity and better cyclability than the Zn₂SiO₄ bulk materials.

An enhancement of specific heat in a ternary molten nitrate salt eutectic doped with nanoparticles at a minute concentration is reported. SiO₂ nanoparticles, whose nominal size is 60 nm, were doped into a ternary nitrate molten salt eutectic (LiNO₃-NaNO₃-KNO₃) at 1% concentration by weight. A modulated differential scanning calorimeter was employed to characterise the specific heat of the eutectic mixture. According to a density weighted specific heat model, the effective specific heat of the mixture should not significantly change since the concentration of the nanoparticles is very small. However, the specific heat of the mixture of eutectic and nanoparticles was enhanced by 13%. From a subsequent material characterisation, a large amount of fractal-like nanostructure formation by the eutectic near embedded SiO₂ nanoparticles was observed. The nanostructure has a very large specific surface area as have the embedded SiO₂ nanoparticles. This can significantly amplify the effect of surface energy on the effective specific heat and is thus responsible for the enhanced specific heat of the mixture. Using the ternary molten salt eutectic with enhanced specific heat for thermal energy storage can significantly increase the energy storage efficiency and thus reduce the cost of electricity in a concentrated solar power system.

A depressurisation method to build SU-8 chambers as pneumatic energy reservoirs is described. The method consists in a combination of injection/extraction of uncrosslinked SU-8 and its exposure in different steps, intended to set the pressure of a chamber below atmospheric. These chambers are intended to be integrated with an actuation system to perform the extraction of fluids from the outside to the inside of a microfluidic SU-8 lab-on-a-chip. This method improves the portability of the platform because external pumps used to impulse the fluids can be avoided.

A novel kind of multi-walled carbon nanotube (MWNT) spongiform adsorbent, with nickel Prussian-blue analogue (NiPB) inside its porous surface was prepared. The carbon nanotube sponge (C/MWNTs) was equipped with large holes and a porous structure, and MWNTs were uniformly distributed in the porous surfaces. The optimal carbonisation temperature of the C/MWNTs as a best substrate for growing NiPB was studied. NiPB particles were fastened on cell walls of the C/MWNTs for ion exchange of cesium in the ternary adsorbent material NiPB/C/MWNTs. The adsorption studies revealed that this novel adsorbent has a good ability to adsorb cesium ions in aqueous solution.