Walnut-like CoS₂ hierarchical structures were synthesised by a simple hydrothermal method. The crystalline phase and morphology of the products were characterised with X-ray diffraction and scanning electron microscope, respectively. The results showed that CoS₂ prepared by hydrothermal method were hierarchical walnut-like materials consist of nanoparticles. As an anode material of Li ion batteries (LIBs), reversible capacity of these CoS₂ materials reached 132.8 mAh/g after 100 cycles. Due to outstanding electrochemical performance, CoS₂ materials can be exploited as a practical anode material for LIBs.

Square-like nano-CeO₂ mingled with Ce(OH)₃ was successfully synthesised via a hydrothermal route using CeCl₃·7H₂O as cerium source, N₂H₄·H₂O as mineraliser, and ethylenediamine as complexant. The as-synthesised nanoparticles were characterised by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, high-resolution transmission electron microscopy, Raman scattering, photoluminescence spectra (PL), and magnetisation measurements. It was found that nano-CeO₂ has a fluorite cubic structure, and there are defects and vacancies in the sample. PL spectrum showed excellent near-UV emission. M–H curve exhibited excellent room-temperature ferromagnetism with saturation magnetisation of 0.0300 emu/g, coercivity of 73.706 Oe, and residual magnetisation of 2.37 × 10⁻³ emu/g, which can be mainly associated with the surface Ce⁴⁺/Ce³⁺ pairs and oxygen vacancies in the nano-CeO₂.

Hierarchical porous ZnMn₂O₄ has been prepared by an initial cotton template and subsequent calcination route. The as-prepared hierarchical porous ZnMn₂O₄ composed of numerous nanoparticles well inherit the fibre-like structure of cotton, and these nanoparticles have a size of ∼20–50 nm. The N₂ adsorption–desorption test indicates this ZnMn₂O₄ has a Brunauer–Emmett–Teller surface area of ∼16.7084 m² g⁻¹ and average pore size of ∼27.0 nm. As lithium ion battery anodes, the ZnMn₂O₄ can deliver a discharge capacity of 674.9 mAh g⁻¹ after 200 cycles at current density of 200 mA g⁻¹. Even at 1000 mA g⁻¹, this ZnMn₂O₄ still shows a stable discharge capacity of 541.5 mAh g⁻¹. These promising electrochemical performances may be attributed to its unique hierarchical porous structure which helps to accelerate the ions transportation and elevate the structure stability.

It has been reported that the sophisticated structure of the Salvinia molesta surface offered a novel mechanism for long-term air-retention. It was difficult to mimic the structure, for it was composed of complex elastic eggbeater-shaped hairs with a coating of nanoscopic hydrophobic wax crystals, except for the top of the hairs. In this work, a structure of fibres cross on a patterned paper to mimic the ability of S. Molesta is manufactured. The complex elastic eggbeater-shaped hairs with a coating of SU-8 photoresist can support a droplet water of 1 ml. This work offered a new simple method to mimic the properties of S. molesta surface.

Nanoporous materials have attracted considerable technological interest due to their wide range of applications. In this study, highly ordered nanoporous anodic alumina substrates (NAAS) were fabricated by two-steps anodisation. Radio-frequency (RF) magnetron sputtering was used to deposit ultrathin Cu layers of different morphologies on the top surface of NAAS. From the field emission-scanning electron microscope images, the Cu/NAAS morphologies were tuned from nanoporous ultra-thin Cu layer, to nanoporous-grains of Cu aggregates, then to a continues layer of Cu nanostones as the deposition time increased from 1 to 4 min. The reflection spectra of the Cu/NAAS samples were dominated with localised surface plasmon modes; longitudinal, transverse and higher-order modes. The surface plasmon resonances of the fundamental and higher-order longitudinal modes were shifted to longer wavelengths as the deposition time increased. In addition, the transverse surface plasmon resonances were shifted to longer wavelengths for deposition time ≤3 min (nanoporous Cu film) and suddenly shifted to shorter wavelengths for deposition time ≥4 min (continuous film). The correlations between the structural parameters and the shift of surface plasmon resonance modes were discussed. The strong red-shifted of the surface plasmon modes to the NIR region suggests a unique opportunity for the design of biomedical sensor based on the proposed structures.

Quaternary compounds Cu₂FeSnS₄ (CFTS), a promising alternative material for solar cell absorber layer, were successfully synthesised by a liquid reflux method in a mixture solvent of triethylenetetramine-ethylene glycol (TETA-EG, 1:1, v/v) at 230°C for 3 h under the atmospheric pressure condition. The phase, micro-structure, morphology, chemical composition and optical properties of the as-synthesised CFTS micro/nano particles were characterised using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectrometry and ultraviolet-visible absorption spectrophotometer. The results showed that the stannite structured CFTS micro/nano particles with close to theoretical stoichiometric ratio were pure and well-crystallised, the particle size ranged from 70 to 240 nm and the particles were well-distributed, the band gap was about 1.25 eV which indicated its suitable application as the absorption layer of thin film solar cells.

A higher-order non-local strain gradient plate model developed for the vibration of piezoelectric nanofilms (PNFs) as nanoelectromechanical mass sensors is presented. The PNF carrying multiple nanoparticles at any locations is subjected to thermo-electro-mechanical loads. Size effects are taken into consideration by introducing three different scale parameters. Using higher-order non-local elasticity, strain gradient theory and Hamilton's principle, the differential equations of motion are derived. Closed-form solutions are obtained for the natural frequencies and frequency shifts of the PNF-based sensor. It is found that the frequency shifts of PNFs can increase or decrease depending on the values of small-scale parameters. The present results would be helpful for designing micro/nano sensors using PNFs.

Two-step direct current electroplating was used to fabricate copper microcylinders with a 50 μm diameter and 150 μm depth. The microstructure was characterised by electron back scattering detection. Twin boundaries appeared and the twin quantity depended on the current density. Near the edge (2 mA/cm²), the grain size was large (∼2 μm) and many twins existed, while the size was small (∼0.5 μm) and few twins occurred in the middle (4 mA/cm²). The hardness was measured by nano-indentation technique. The results showed that the hardness (2.7 GPa) at the edge of the sample was higher than that in the middle (2.2 GPa), which was probably enhanced by twins. The hardness of annealed sample was about 1.7 Gpa, which was independent of the position.

Silver nanoparticles (AgNPs) were biosynthesised by reducing silver nitrate (AgNO₃) using Ambrosia maritima aqueous leaves extract. The biosynthesised AgNPs were characterised by transmission electron microscope, Fourier transform infrared spectroscopy and zeta potential analyser. The nanoparticles were generally found to be spherical in shape with average size of 30 nm and were stable at zeta potential of −26.29 mV. The data collected by cyclic voltammetry, ultraviolet–visible (UV–Vis) spectrophotometer and spectrofluorophotometer proved the characteristic electrochemical and optical properties of the biosynthesised AgNPs. The metallic nanoparticles showed an anodic peak at 0.4 mV, a surface plasmon resonance peak at 437 nm and a fluorescence emission peak at the wavelength of 467 nm. In conclusion, AgNPs biosynthesised using A. maritima proved to be compatible and feasible to be studied further in in vitro and in vivo systems. Overall, the biosynthesised AgNPs can be used as a tool applied in a broad range of industrial and medical applications.

Pd–B amorphous alloy was successfully supported on the surface of natural nanoclay palygorskite (PAL) via a simple chemical reduction method. Compared with the conventional supported Pd catalyst, the Pd–B/PAL amorphous catalyst possessed the ultra-high selectivity (100%) to o-chloroaniline (o-CAN) in the hydrogenation of o-chloronitrobenzene (o-CNB) to o-CAN and avoided the dechlorination of o-CNB. XPS analysis results indicated that PAL support could reduce the electron density of Pd atoms and suppressed the hydrogenolysis of C–Cl bond. Meanwhile, the Pd–B/PAL amorphous catalyst exhibited a good stability and is a prospective catalyst for the selective hydrogenation of CNB to CAN.

A novel dual metal gate doping-less vertical tunnel field effect transistor (D-VTFET) on silicon body, using work function engineering is proposed. The proposed structure does not required impurity doping for formation of the drain and the source regions. In this concern, source and drain regions are formed by selecting appropriate work-function of metal electrode. The source and drain regions are not formed by conventional ways of ion implantation or diffusion. Hence, proposed structure is immune greatly to the process variation, issues of doping control and random dopant fluctuations which are serious problems in ultrathin silicon devices. For further improvement in ON state current and analogue/RF figures of merit dual work function of single gate material is considered. The electrical characteristics of the proposed device with the D-VTFET are simulated and compared.

In this work, TiO₂ nanofibers (TiO₂-NF) with multilevel structure and nanoparticles (TiO₂-NP) were respectively prepared via template-assisted and single solvothermal methods. The degradation of methylene blue (MB) was used as the model reaction to evaluate the photocatalytic properties of these prepared materials. It was important that TiO₂-NF, prepared via template-assisted solvothermal method, possessed multilevel structure. The photocatalytic results indicated that their activity order was TiO₂-NF > TiO₂-NP. It demonstrated that the multilevel structure of TiO₂-NF played an important role for enhancing its photocatalytic activity and the enhanced property could be mainly ascribed to fast adsorption/desorption of MB molecules on its surface and high efficiency of absorbing irradiating light and the efficient electrons transfer by interparticles and interparticles to the wall of the fiber.

A resonant pressure sensor with piezoelectric excitation and sensing is presented, which is realised by combining a micromachined diaphragm and a quartz resonator. The sensor performance is improved by introducing double enhancement beams into the diaphragm. Finite element method is utilised to reveal the validity and optimise the structural dimensions. A self-excitation circuit is designed to drive the resonator into steady oscillation. The sensor chip is fabricated by bulk micromachining technologies and packaged in a metal shell in the inert gas environment for characterisation. The performance characteristics including the short-term drift, temperature characteristic and quality factor are investigated. The experimental results demonstrate that the sensor features a high sensitivity of 100.45 Hz/kPa and a short-term drift <14 ppm in the operating range of −10∼10 kPa at room temperature. Owing to the excellent performance in sensitivity and accuracy, the sensor can be applied for micropressure measurement.

A new Al–4.2 wt.% Ti(C_0.7, N_0.3) master alloy with a uniform microstructure was successfully prepared by casting method. Grain refining test indicates that Al–4.2 wt.% Ti(C_0.7, N_0.3) master alloy exhibits an excellent grain refining performance on commercial pure aluminium and the average grain size of pure Al can be effectively refined to 130 µm from about 3000 µm after adding 0.1 wt.% Ti(C_0.7, N_0.3) particles by Al–4.2 wt.% Ti(C_0.7, N_0.3) master alloy. The tensile strength and elongation are increased by about 20.5% from 55 to 66.3 and 14.9% from 39 to 44.8 due to the grain refinement by adding Al–4.2 wt.% Ti(C_0.7, N_0.3) master alloy. Compared with Al–5Ti–1B master alloy, Al–4.2 wt.% Ti(C_0.7, N_0.3) master alloy has a slightly better ability in improving the mechanical properties of pure aluminium due to the better grain refining performance.

Truncated octahedral cuprous oxide (Cu₂O) crystallites with highly uniform morphologies and sizes ranging from 2.4–2.5 µm were prepared by using a green and convenient approach and their antibacterial activities were studied. They were obtained through the chemical reduction of copper chloride by glucose in the presence of sodium hydroxide and polyethylene glycol at room temperature for 2 h. X-ray powder diffraction, energy dispersive spectrometer, scanning electron microscopy, and transmission electron microscopy as well as high-resolution transmission electron microscopy (HRTEM) were used to characterise the obtained products. Structural analysis revealed that these truncated octahedral crystallites were composed of eight {111} faces and six {200} faces. The effects of time, temperature and polyethylene glycol on the formation of truncated octahedral cuprous oxide were investigated. The possible growth process and mechanism of truncated octahedral cuprous oxide were proposed. The antibacterial activities of truncated octahedral Cu₂O were also explored. They exhibited significant antimicrobial activity against both gram-negative and gram-positive bacteria. The result of antibacterial study revealed that the prepared Cu₂O can be a promising candidate for wide range of bio-medical applications.