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In this work, a novel triad nanocomposites containing trititanate nanotubes, Ag nanoparticles and dopamine were prepared and the SERS properties were measured experimentally. Control over the size and position of the Ag nanoparticles in the TiNT-dop-Ag system, along with the localised surface plasmon resonance (LSPR) of the Ag particles matching the Raman excitation wavelength, gives a SERS enhancement greater than 6 orders of magnitude. Electromagnetic modelling was used to provide a theoretical basis for these results.

A novel Cu2O-Au-BFO heterostructure photocathode was constructed which significantly improved the efficiency of photo-generated carrier transfer for solar hydrogen production. A BiFeO3 (BFO) ferroelectric film was synthesized on top of a Cu2O layer by a sputtering process. The BFO layer acted to protect the Cu2O layer from photochemical corrosion, increasing photoelectrochemical (PEC) stability. The p–n heterojunction between Cu2O and BFO layers enhanced the PEC properties by suppressing charge recombination and improved interfacial charge transfer efficiency. When Cu2O and BFO are interfaced by Au Nanoparticles (NPs) the PEC performance was further enhanced, due to hot-electron transfer at the plasmonic resonance. After positive poling, the depolarization field across the whole volume of BFO film drove electrons into the electrolyte solution, inducing a significant anodic shift, Vop of 1.01 V vs. RHE, together with a significantly enhanced photocurrent density of −91 μA/cm2 at 0 V vs. RHE under 100 mW/cm2 illumination. The mechanism was investigated through experimental and theoretivcal calculations.

We studied differences in localizing the centres of flow in radially expanding and contracting patterns in different regions of the visual field. Our results suggest that the perceived centre of a peripherally viewed expanding pattern is shifted towards the fovea relative to that of a contracting pattern, but only in the lower right and upper right visual quadrants and when a single speed gradient with appropriate overall speeds of the trajectories of the moving dots was used. The biases were not systematically related to differences of sensitivity to optic flow in different quadrants. Further experiments demonstrated that the biases were likely due to a combination of two effects: an advantage of global processing in favor of the lower visual hemifield and a hemispheric asymmetry in attentional allocation in favor of motion-induced spatial displacement in the right visual hemifield. The bias in the lower right visual quadrant was speed gradient-sensitive and could be reduced to a non-significant level with the usage of multiple speed gradients, possibly due to a special role of the lower visual hemifield in extracting global information from the multiple speed gradients. A holistic processing on multiple speed gradients, rather than a predominant processing on a single speed gradient, was likely adopted. In contrast, the perceived bias in the upper right visual quadrant was overall speed-sensitive and could be reduced to a non-significant level with the reduction of the overall speeds of the trajectories. The implications of these results for understanding motion-induced spatial illusions are discussed.

Inorganic particles have been widely used as fillers for stiffness enhancement of polymers. In this paper, the filler particle size is fixed, and relationship between filler fraction and elastic modulus has been studied in Al(OH) 3 /polyethylene composites. By measuring the elastic moduli of composite samples with different filler content, the highest value of elastic modulus is found around 40% filler weight fraction. In distance-dependent elastic modulus analysis the peak elastic modulus of PE is obtained at a distance of 430 nm to filler center, which corresponds with body-centred cubic packing type. Our research may be helpful in improving mechanical property of polymer materials.

Funding: Xi'an Jiaotong Liverpool University. Grant Number: RDF- RDF-16-01-06. The surface enhanced Raman scattering of trititanate nanotubes (TiNT) modified with enediol ligands was investigated and it was found that the functional group dramatically affects the enhancement observed. For TiNT‐4‐nitrocatechol, a SERS enhancement is seen; however, when dopamine is attached, no signal is seen. The relative band gap positions upon 785 nm laser excitation are proposed to explain the observed phenomenon. This attachment is investigated by solid state NMR and UV/Vis spectroscopy and supported by DFT calculations to offers further insights into catechol coatings of nanomaterials and SERS by the chemical method. We expect this non noble metal containing composite material to have applications in bioimaging and bio and chemical detection. Postprint

Herein, a TiO2 NTAs-Au-MoS2 core–shell photoanode was constructed with the intention to fulfill the efficient transfer of photo-generated carriers to the photoelectrode’s surface. Au nanoparticles were decorated by a drop casting method, and the MoS2 layer was deposited above the Au nanoparticles using a photoreduction-annealing process. Au nanoparticles were well dispersed on the inner wall of the TiO2 nanotubes and covered by the MoS2 layer, forming a core–shell nanostructure. The MoS2 layer significantly improved the attachment between Au nanoparticles and TiO2 NTAs, resulting in increased PEC stability and performance. Attributed to the excitation of Au nanoparticles’ localized surface plasmon resonance effect and visible light utilization of MoS2, the TiO2 NTAs-Au-MoS2 core–shell photoanode exhibits greatly enhanced photocurrent density. An increase from 67[Formula: see text][Formula: see text]A/cm2 to 234[Formula: see text][Formula: see text]A/cm2 under Xe lamp illumination and from 2.6[Formula: see text][Formula: see text]A/cm2 to 12.6[Formula: see text][Formula: see text]A/cm2 under visible light illumination ([Formula: see text][Formula: see text]nm) compared with the TiO2 NTAs was observed.

Mixed phase TiO2 powders of different composition and particle size were subjected to the hydrothermal reaction with 10 M NaOH. It was found that the anatase phase component of the starting material is easily converted to trititanate nanotubes at 140 °C. At this temperature the rutile phase remains unreacted, however at 170 °C it reacts to form trititanate plates and belts. When the reaction time is increased to 7 days, all the TiO2 is converted to trititanate and the morphology is exclusively nanoplates and belts, with the tube phase destroyed. Many researchers have observed some heterogeneity in their reaction products, but have mainly focussed on the nanotubes. We observed that the tubes are only prepared from the anatase phase component of a TiO2 precursor, whereas the rutile component produces trititanate plates and sheets, irrespective of the reaction length. The particle size affects the rate of reaction, resulting in the phase transition being more easily visible in the reactions starting with the larger TiO2 particle size.

A comparative study of the microstructure and dielectric properties between Ba 1− x Ca x TiO 3 (BCT) ceramics and films were performed in the whole Ca concentration range of x = 0–1. The ceramics were prepared by conventional solid-state reaction technique and the films by the method of pulsed-laser deposition. X-ray diffraction (XRD) study of the BCT ceramics exhibited a pure tetragonal phase for x = 0–0.25, a tetragonal–orthorhombic diphase for x = 0.25–0.85 and a pure orthorhombic phase for x = 0.90–1.00. And the dielectric phase transition temperature from tetragonal to cubic was marginally affected by the Ca doping into BaTiO 3 . However, BCT films deposited on Pt/Si/SiO 2 /Si substrates showed a different microstructure and dielectric properties. Tetragonal–orthorhombic diphase was not found in the BCT films for x = 0.25–0.85, and a large decrease of the Curie point and diffuse phase transition were observed in the BCT films. Based on the compositional analysis, such phenomena were ascribed to the occupancy of some Ca 2+ to the Ti 4+ sites in the BCT films.

The dielectric and ferroelectric properties of (BaxSr1−x)0.77Ca0.23TiO3 ceramics with x = 1 to 0.7 were studied and compared with those of BaxSr1−xTiO3 and Ba0.77Ca0.23TiO3 ceramics. It has been found that Sr doping of the Ba0.77Ca0.23TiO3 ceramics causes a drastic decrease of the Curie temperature, just like Sr doping of pure BaTiO3 ceramics, demonstrating a cell volume effect. However, the (BaxSr1−x)0.77Ca0.23TiO3 ceramics with x = 0.9 and 0.8 have larger spontaneous polarization than those of the corresponding BaxSr1−xTiO3 and Ba0.77Ca0.23TiO3 ceramics, along with sufficient insulating properties. The enhancement of their polarization was explained by the increase of the lattice parameter c / a ratio due to the lattice distortion and strain developed in the ceramics.

Pb(Zr(0.2)Ti(0.8))O3 wrapped CaFe2O4 particles were constructed on ITO coated quartz as a photocathode for efficient water splitting. A photocurrent of 152 μA cm(-2) was obtained under zero bias vs. Ag/AgCl and 100 mW cm(-2) with the assistance of positive poling and Ag decoration.

For efficient utilization of solar light during photoelectrochemical (PEC) water splitting, tandem photoelectrodes comprising a wider bandgap top semiconductor stacked above a smaller bandgap one have been proposed in the previous studies. However, the photocurrent is usually limited due to the blocked transfer of photogenerated carriers on the interface between the semiconductors. Here, this study constructs an Si-pnn+/ITO/Au/BiFeO3 (BFO) hybrid photocathode catalyzed by MoS2/Pt with an intension to fulfill the efficient transfer of photogenerated electrons from Si to electrode surface. This study reveals how the local surface plasmonic resonance effect of Au nanoparticles and the depolarization electric field of BFO enhance the PEC reactivity of the photocathode, and also the catalytic effect of the combined MoS2/Pt catalyst. Remarkably, the photocathode exhibits an onset potential of 1.3 V versus reversible hydrogen electrode (RHE), and the photocurrent at 0 V versus RHE can be up to –9.1 mA cm−2 under 100 mW cm−2 Xe-lamp illuminations. Such a unique design represents a general strategy to enhance the PEC performance of a tandem photoelectrode where the energy bands are not so matched on the interfaces, and therefore extends the scope of the tandem architectures.