This study used dithizon (DZ) and mesoporous as a sorbent for simultaneous removal of heavy metal (mercury, cadmium and copper) ions from aqueous solution and real samples. Santa Barbara Amorphous synthesised and characterised by X-ray diffraction, Fourier-transform infrared spectroscopy and Brunauer–Emmett–Teller. Heavy metal ions measured by atomic absorption spectrometry and inductively coupled plasma optical emission spectrometry. Optimised conditions such as pH, removal time, sorbent dosage and concentration analyte with central composite design and obtained 5, 20 min, 20 mg and 25 ppm, respectively. The equilibrium data were fitted to isotherm models such as Langmuir, Freundlich and Tempkin and the results revealed the suitability of the Langmuir model. The maximum adsorption capacities for Hg²⁺, Cd²⁺ and Cu²⁺ ions achieved 25.04, 30.3 and 31.79 mg/g, respectively. Kinetics data fitting to pseudo-first order, pseudo-second-order and Elovich models confirmed the applicability of pseudo-second-order kinetic model for the description of the mechanism and adsorption rate. This sorbent could regenerate easily with ethylenediamminetetraacetate solution.

In this study, a flame retardant [Pollen-type SnO₂ (P-SnO₂)] with a micro/nanoporous structure was synthesised by the simple immersion–calcination method using pollen as a biological template. When applied into flexible polyvinyl chloride (PVC), PVC composite adding P-SnO₂ (PVC/P-SnO₂) exhibited much better mechanical property than that adding commercial SnO₂ (PVC/[C-type SnO₂ (C-SnO₂)] for the results that the tensile strength and impact toughness are increased by 11.3 and 37.9%, respectively. Moreover, PVC/P-SnO₂ has always the same flame retardancy and smoke suppression abilities compared with PVC/C-SnO₂. It provides a method using biotemplate for preparing metal oxide flame retardants with both great flame retardant and toughening properties.

The construction of transition metal oxides/carbon composites has been one of the most useful methods to improve the electrochemical performances of transition metal oxides as anodes of lithium-ion batteries (LIBs). It has been found that various carbon amounts will make a great effect on the structures and properties of composites. In this work, the MnO/cotton based carbon composites are immediately obtained at an inert atmosphere from Mn(NO₃)₂–cotton mixture, which is readily produced based on the adsorption characteristic of cotton. The influences of carbon contents derived from various cotton amounts on the structures and electrochemical properties of MnO are studied. The results show that decreased crystallinity and improved porous properties can be achieved with increased carbon contents. As LIBs anodes, their electrochemical behaviours are distinct and deeply influenced by carbon contents. The MnO/cotton based carbon composite obtained at a cotton amount of 0.3 g delivers an initial reversible discharge capacity of 812.4 mAh g⁻¹, and a capacity of 775.9 mAh g⁻¹ can be retained after 50 cycles. Meanwhile, the structure–function relation is also discussed in the text.

This work report a facile, rapid and efficient approach to prepare high-concentration graphene and MoS₂ nanosheets through the liquid phase exfoliation of bulk materials with the method of high-pressure homogenisation assisted by carboxyl methyl cellulose. The few-layer graphene and MoS₂ nanosheets dispersions are prepared under 100 MPa for 10 min at high concentrations up to 1.45 and 0.28 mg/ml. The two nanodispersions could be applied to prepare the polyvinyl alcohol composite with well dispersibility and thermal stability.

The mesoporous CoTiO₃ nanoparticles, which have been successfully prepared by a fast, simple and low-cost hydrothermal method, show good decolourisation and degradation of methylene blue (MB). The synthesised samples can be recovered easily from solution by a magnetic mass. Surface morphology, structure, composition, and optical characteristics of the prepared CoTiO₃ were determined using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and ultraviolet–visible absorption measurements. The degradation percentage of MB was nearly 95% at an initial concentration of 10 ppm in 90 min. Such enhanced photocatalytic activities of synthesised CoTiO₃ were attributed to a large specific surface area (54.22 m² g⁻¹) and defects density, which was useful for restraining surface recombination of photo-generated charge carriers. The recovery of CoTiO₃ nanoparticles was about 85% and the degradation rate of MB remained 80% after five cycles. As a whole, the CoTiO₃ nanocomposites give a synergistic effect in photocatalytic and magnetic behaviour and indicate that the synthesised samples have a promising potential particularly for water purification and environmental remediation.

Shared aperture based 2 × 2 matrix shaped patch antenna is described here. The 2 × 2 matrix based patch antenna with optimised dimensions is designed from a rotated hollow square shape based patch. Out of four elements, two diagonally placed elements are acting as resonating elements (for L-band and S-band separately); rest two acting as parasitic elements. The proposed prototype has a measured impedance bandwidth of 1.54–1.7 GHz in L-band (S ₁₁<−10 dB) and 3.7–4.2 GHz in S-band (S ₂₂<−10 dB). Isolation is better than 20 dB in both cases, with reduced cross-polarisation, due to the presence of the parasitic elements. Details of the proposed prototype and design procedure are given; the experimental results are also discussed along with potential advantages and applications. The proposed antenna is designed and fabricated using FR-4 substrate (90 mm × 90 mm).

Titanate nanotube thin (TNT) films were synthesised by alkaline hydrothermal method using titanium (Ti) plates as precursors. Copper–cobalt (Cu–Co)-codoped titanate/Ti dioxide (TiO₂) nanocomposite thin films were prepared by doping Cu and Co to TNT films through ion exchange method and annealed at 500°C for 120 min. The as-prepared nanocomposite films were characterised by scanning electron microscopy, transmission electron microscopy, X-ray diffractometer, and ultraviolet–visible absorption spectra. The results show that anatase TiO₂ particles were grown on the surface of titanate nanomaterial films. The composite materials mainly consisted of anatase TiO₂ particles and titanate nanotubes/nanosheets. Cu–Co-codoped titanate/TiO₂ nanocomposite thin films exhibited superior visible height adsorption property due to the reduced energy bandgap of composites introduced by additional Cu and Co 3d orbitals.

In this work, porous polycaprolactone (PCL) scaffolds were designed and fabricated using selective laser sintering (SLS). The critical processing parameters of the SLS for PCL were optimised. This work post-processed these PCL scaffolds to produce PCL/alginate/polyacrylamide (PAAm) scaffolds to improve their performance. The experiment mechanical property assessment showed that the sample's average elastic modulus increases from 6.99 MPa (PCL) to 12.67 MPa (PCL/alginate/PAAm), and the elongation at break of samples increases from 59% (PCL) to 112.9% (PCL/alginate/PAAm). Cell seeding and in vitro culture showed that cell viability remained above 94% over 5 days. Thus, the current study suggests that a promising strategy for the improvement of the characteristics of PCL/alginate/PAAm scaffolds and advances the potential application of SLS technique towards skeletal tissue repair.

In this work, nickel oxide nanoparticles (NiO NPs) have been synthesised via cost-effective and highly convenient co-precipitation method, using cetyl trimethyl ammonium bromide (CTAB) as capping agent and NaOH as a reducing agent. The as-synthesised NPs have been analysed by a number of spectroscopic and microscopic techniques such as UV–visible spectroscopy, transmission electron microscope, X-ray diffraction, Fourier transformed infrared and energy dispersive X-ray. The prepared NiO NPs hold the prodigious potential towards the photocatalytic degradation of reactive blue 81 and Coomassie brilliant blue R-250 dyes with degradation efficiency of 90.8 and 95.7% and have high dye degradation rate constants of 1.3 × 10 ^{− 2} min ^{− 1} and 2.2 × 10 ^{− 2} min ^{− 1}, respectively. Thus, this work signifies an efficient way to employ the NiO NPs as effective photocatalyst towards the alleviation of noxious industrial dyes.

Photolithography, typically used to create microchannel networks on silicon to fabricate the template for microfluid devices, has the drawback of requiring sophisticated instruments, available only in few premier fabrication units. Template fabrication thus was a privilege of few researchers. Through the years, researchers economised the process of device development using a three-dimensional (3D) printer which directly projected non-planar structures on to a photo-curable resin. Devices thus built lacked the versatility of polydimethylsiloxane (PDMS). The novelty of this work is to use the 3D printing resin for template fabrication and subsequent device development with PDMS. In this way, cost reduction and ease of template generation are substantially enhanced while retaining the advantages of a PDMS device. Unlike directly printed devices that are formed from ultraviolet curable photopolymer, this method fabricates the master with cured photopolymer used in 3D printing. The master pattern is transferred to PDMS for subsequent processing to construct the device. Compared to devices built on silicon templates, PDMS on polymer templates necessitate careful curing at a lower temperature. Low-temperature PDMS–substrate bonding has also been studied in this work. Fabricated device has channel dimensions in the order of 200–300 μm and has been used to study various oil–water emulsions.

An environmentally friendly and facile method for the synthesis of small-sized Au–Ag alloy nanoparticles is proposed. The method involves the coreduction of HAuCl₄ and AgNO₃ using Lysimachia christinae polysaccharide as reductant and stabiliser at 85°C. The synthesised alloy nanoparticles with a mean diameter of 3.81 nm are stable in solution due to the stabilising effect of the polysaccharide. Furthermore, Au–Ag nanoparticles have first been introduced into cigarette filter to serve as a synergistic catalyst for reducing CO in mainstream smoke.

A novel ZnO nanorod array/reduced graphene oxide (ZnO array/rGO) composite coating was synthesised via the combination of seed layers-growth and aqueous solution reaction for the formation of ZnO nanorod arrays, which was further combined with rGO using a simple water bath method. The results revealed that perpendicular arrays with hexagonal planes were successfully fabricated. The size and density of the arrays could be optimised by adjusting the reactant concentrations. The influence of the rGO fraction in the ZnO array/rGO composites on the photocatalytic degradation of the methylene blue under UV radiation was investigated. It was found that the photocatalytic performance could be significantly improved by adding rGO. The enhanced photocatalytic activities were attributed to the interactions between ZnO nanorod arrays and rGO nanosheets and subsequently effective separation of photo-generated electron-hole pairs via rGO as electron sinks. The ZnO array/rGO composites presented advantages including facile and green preparation, long photo-electron lifetime, easy particle agglomeration and recovery, and therefore is expected to be an ideal photocatalysts for the future utilisation.

CuGaO₂ has been receiving much attention due to its potential as photocathode instead of NiO for p-type dye sensitised solar cells (p-DSSCs). The improvement in the photovoltaic performance of such devices also depends on the increase of the efficient dye loading by significant enhanced specific surface areas. This work reports for the first time the fabrication of the three-dimensional (3D) hierarchical flower-like CuGaO₂ nanostructures in a high uniformity by a facile one-step hydrothermal synthesis. The growth mechanism and the effects of the reaction parameters (time and reducing agent) on the formation of the 3D hierarchical flower-like CuGaO₂ nanostructures were investigated in detailed. It is significantly to note that the prepared 3D hierarchical flower-like CuGaO₂ nanostructures exhibit the highest specific surface areas reported (60 m²/g with ethylene glycol). Due to the efficient dye loading by high specific surface areas, the performance of p-DSSCs based on delafossite CuGaO₂ is enhanced. Thereby, based on the optical investigation, electrochemical impedance measurement and Mott–Schottky plots, the improved performance can be attributed to high loading of the dye molecules, the enhanced light-scattering and the reduced interface recombination.

Monodisperse zirconia microspheres were prepared by homogeneous urea precipitation method. The effect of reaction time, reaction temperature and other synthetic parameters on the dispersion of the product was investigated in this experiment. The as-prepared zirconium oxide (ZrO₂) powders were characterised by X-ray diffraction, Brunauer–Emmett–Teller analysis, field emission-scanning electron microscopy and Fourier-transform infrared spectroscopy. The experimental results show that the size and dispersion of ZrO₂ microspheres can be controlled by changing the concentration of polyvinylpyrrolidone (PVP). The size of ZrO₂ microspheres is changed from 120 nm to 1 μm with the increase of PVP concentration. When the reaction temperature is raised to 90°C and the reaction time is reached to 2 h, the monodisperse ZrO₂ microspheres with a diameter of 120 nm are finally prepared. ZrO₂ ceramics possessed an ultrafine, uniform microstructure and a narrow pore size distribution, and the grain size increased from 72 to 190 nm with the increase of sintering temperature. Moreover, when ZrO₂ ceramics were sintered at 950°C for 2 h, the theoretical density was up to about 98% (a density of 5.65 g/cm³), which is higher than that of conventional ZrO₂ ceramics.

Microrobots could become a key enabler in life science and medicine research as well as industrial applications. Although they provide high-performance tools for a wide range of applications, their environment and particularly surface forces induce significant challenge for their control. This work introduces an originally integrated microrobot in a permanently sealed glass microfluidic chip. Compared to conventional polymer chips, the glass substrate offers a smooth, stable, and inert surface. It also avoids the typical contamination and fast degradation of organosilicon polymers. In this environment, they demonstrate high-frequency hydrodynamics analysis and control. This strategy offers a high precision platform to study microrobot design and hydrodynamics as well as a transducer module for mapping surfaces and sensing interaction with physical environments.

Dendritic silver hierarchical structures were prepared via a simple electrochemical deposition method in the presence of citric acid. The influence of the molar ratio of citric acid and AgNO₃, the deposition time and the deposition current on the crystalline and morphology of the products were studied by X-ray diffraction and scanning electron microscopy. Dendritic silver hierarchical structures consist of a long trunk with secondary branches, which grew in a parallel direction with a definite angle to the trunk. The average diameter of the trunk is 230–320 nm, that of the secondary branches is about 250 nm and the length of the branches is about 850 nm. The charge specific capacity of dendritic silver hierarchical structures was stable at around 250 mAh g⁻¹ after 500 cycles at 0.1C. They also exhibited excellent rate capability at the various current rates from 0.1 to 5C.

This work has assembled ZnSe:Mn/ZnS quantum dots (QDs)-monoclonal anti-microcystin-Leucine Arginine (anti-MC-LR) antibody bioconjugates as a room temperature phosphorescence (RTP) probe using 1-ethyl-3-(3-dimethyllaminopropyl) carbodiimide/N-Hydroxysuccinimide chemistry for detecting MC-LR. Once the specific interactions occurred between these MCs and their antibodies on the surface of ZnSe:Mn/ZnS QDs, the RTP of ZnSe:Mn/ZnS QDs was quenched with the increased concentration of MC-LR. Under the optimised conditions, the linear range of MC-LR was determined to be 0.9–8.8 nM. The linear relationship between (P ₀–P)/P ₀ and concentration of MC-LR were observed with the regression equation (P ₀–P)/P ₀ = 0.03908C + 0.0456 with the detection limit of 0.038 nM. The developed RTP immunoassay favoured environmental applications since the interference from autofluorescence and scattering light was greatly eliminated.

This is the first report on the investigation of a hybrid plasmonic tapered coupler injecting light efficiently from conventional dielectric waveguide to a hybrid insulator–metal–insulator (HIMI) plasmonic waveguide. The proposed structure gives high transmission efficiency and suppresses the reflection losses significantly. With this tapered coupling mechanism, maximum transmittance and return loss of 98% and 26 dB have been observed, respectively. The coupler also offers very good propagation length (274 μm) along with minimal mode propagation losses (0.016 dB/µm). Apart from that, it offers decent confinement of light in low dielectric regions up to 32%. The proposed structure is designed in an ultra-short tapered length of 1.0 µm, and the entire structure occupies a footprint area of 1.4 × 2.4 μm². Proposed hybrid waveguide coupler could be useful for several chip scale applications.

A planer structure of a tunnel field effect transistor (TFET) faces many consequences of fabrication complexity and less controllability of the gate electrode over the channel. Therefore, in this Letter nanowire TFET (NW TFET) is presented for the biosensing application. For this purpose, a new design approach of NW TFET has been presented to overcome the issues of planer structure TFET and for improving sensitivity and sensing speed of the biosensor. In this concern, an addition electrode is placed around the source region and the cavity, which is generally created in the oxide region under the gate electrode, is extended towards the source oxide region. Thus, due to the presence of source electrode, additional holes are accumulated in the source surface region and forming a plasma layer of holes. Hence, abruptness at source/channel junction is created. So as the biomolecules enter into the cavity, the large variation is observed in electrostatic properties of the device due to different properties (dielectric/charge) of the biomolecules. These variations reflect as improved sensitivity of the biomolecule detector. Further to this, because of the supplementary source electrode, abrupt source/channel junction provides lower subthreshold swing, which reduces the response time of the device and increases the sensing speed of biomolecules detection.

The high-strength of Ti-1Al-8V-5Fe (Ti-185) alloy is due to TiH₂ powders produced at different compaction pressures and compared with hydride–dehydride-Ti powders. The objective of this work was to investigate the microstructural evolution and mechanical properties of Ti-185 alloy under different compaction pressures. The dehydrogenation characteristics of TiH₂-185 and the oxygen contents of sintered samples were evaluated by thermogravimetric analysis and mass spectrometer (TG-MS) and oxygen/nitrogen (O/N) analysers. The corresponding microstructural evolution and change in mechanical properties were analysed by means of scanning electron microscopy, X-ray diffraction, electro-universal tester, and hardness tester, respectively. Results show that with the increase in compaction pressure, the green and sintered density and densification rates increase, but the volume fraction of α-phase decreases. The TiH₂-185 samples have higher densification and sintered density, lower oxygen content than Ti-185 samples, which is attributed to its better compressibility and superior self-cleaning ability as well as more water produced. In addition, the sintered TiH₂-185 samples exhibit higher yield strength and hardness in comparison with the sintered Ti-185 samples. The enhanced mechanical properties are attributed to its higher density and less soft α-phase in the microstructure.

A new heterojunction BiOXs/TiO₂ photocatalyst was firstly prepared by a mixed solvothermal method. Several tools were used to characterise the structure and morphologies of as-obtained samples. The results of photocatalytic experiments indicated that flower-like BiOXs/TiO₂ fabricated by the thinner nanosheets exhibited excellent degradation properties towards methyl orange, bisphenol A and tetracycline under visible-light irradiation. The reasons could be the good absorption of organic pollutants and light, and the high separation efficiency of photogenic electrons and holes attributed to the construction of BiOXs/TiO₂ heterojunction with large special surface areas. The photocatalytic mechanism was proposed. This Letter could provide new ideas to design the visible-light catalysts.

A novel type of active Pb was electro-deposited on a porous graphite/Pb conductive substrate to form Pb-graphite-Pb (PGP) composite material, which was used as a positive electrode to study its electrochemical performance. The scanning electron microscopy images of the electrochemically treated graphite/Pb conductive substrate show that the substrate possesses a three-dimensional porous structure. The active lead is uniformly deposited on the surface of the graphite/Pb substrate, which ensures the stability of the electrode structure and avoids collapse. The cyclic voltammetry (CV) results show that PGP composite has high conductivity and contains multiple redox peaks in different potential intervals. By analysing the CV diagram, the charge–discharge voltage is set at 2.2 V, which shows that the initial specific capacity of the battery can reach 218.2 mAh/g. After 200 cycles, the capacity still reaches 191.4 mAh/g, and the capacity retention rate is 87.7%. These values indicate that the battery composed of the novel graphite/Pb composite has a high initial specific capacity and good stability.

Recently nanowires, especially silicon nitride (Si₃N₄), have been the emphasis of recent researches, due to their potential application. In this work, the authors developed a catalyst-free method to prepare Si₃N₄ nanowires by heating the mixture of Si powder and SiO₂ sol, coupled with carbon felt at 1500°C in a N₂ atmosphere. The nanowires were composed of α-Si₃N₄ and β-Si₃N₄, with lengths of 1–2 mm and diameters of 1.5 μm. Meanwhile, the vapour–solid mechanism was employed to interpret the nanowires growth, and this method may be applied to synthesise other long nanowires.

This work studies the wave propagation in embedded single-walled carbon nanotubes (CNTs) conveying fluid and placed in multi-physical fields based on the non-local higher-order strain gradient model with surface effect considered. The nanotubes are modelled as Timoshenko beams. Utilising Hamilton's principle, the governing equations of wave motion in CNTs are derived. The solution for the phase velocity of wave motion is obtained, which can not only consider the stiffness softening effect but also reflect the stiffness enhancement effect of scale parameter observed by experiments. The numerical simulations are conducted to compare the results on the basis of different order non-local strain gradient models. It is shown that the behaviours of wave propagation based on the non-local higher-order strain gradient models are quite different from those based on the classical continuum model. In addition, the scale and surface effects and influences of various external factors including inner flow, surrounding medium, temperature field, and magnetic field on the wave dispersion are investigated.

A series of conjugated donor–acceptor (D–A) block copolymers (BCPs) were synthesised using a one-pot Stille coupling polycondensation reaction. This involved reaction between a series of mono-bromo-functionalised Poly3-hexylthiophene (P3HT) polymers (P3HT-Br, M_n : 17, 21 and 43 kg/mol) and [N, N′-bis(2-decyl-tetradecyl)-1,7-dibromo-3,4,9,10-perylene diimide (PBI) and [2,5-bis(trimethylstannyl)-thiophene] (T) monomers. Purification using preparative gel permeation chromatography (GPC) removed any excess P3HT and resulted in BCPs with low polydispersity index values. The P3HT-b-PBIT BCPs were characterised using ¹H-NMR and Fourier-transform infrared spectroscopy. When compared to a P3HT/PBIT polymer blend, the D–A BCP films exhibited a remarkably fine structure with a nanoscale morphology. These results indicated that these D–A BCPs have the potential for use as nanostructured active layers in polymer solar cells.