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The Cu-CeO2metal-support interaction was enhanced via mix-MOF pyrolysis to promote water-gas shift reaction performance.

The formate path is favored on Pt0sites in Pt/CeO2:Tb with abundant oxygen vacancies while the carboxyl path with a higher rate is favored on Ptδ+sites in PtFe/CeO2.

Developing efficient electrocatalysts toward oxygen evolution reaction (OER) is of great significance for improving the efficiency of hydrogen production by electrolysis of water. The transition metal-based heterostructure shows superior catalytic performance toward OER due to abundant defects and a modified electronic structure of the active sites. Herein, we synthesized a NiO and CuO heterostructured nanosheet rich in defects on the Ni foam via an in situelectrochemical oxidation. The electrocatalyst showed high OER activity with an overpotential of 234 mV at 10 mA cm–2and a small Tafel slope of 22 mV dec–1. To our knowledge, this is the first time that the NiO and CuO heterostructure, which was obtained by a very simple preparation method, has been used in OER. The excellent catalytic performance can be attributed to electron interactions between NiO and CuO, thus modifying the adsorption energy of nickel oxide to intermediate species. Moreover, we found that the heterostructured nanosheet was composed of many very small NiO and CuO nanocrystals with abundant defects and more exposed active sites, thus improving the catalytic activity and accelerating the kinetic processes of OER.

Topological design of materials enables topological symmetries and facilitates unique backscattering-immune wave transport. In airborne acoustics, however, the intrinsic longitudinal nature of sound polarization makes the use of the conventional spin–orbital interaction mechanism impossible for achieving band inversion. The topological gauge flux is then typically introduced with a moving background in theoretical models. Its practical implementation is a serious challenge, though, due to inherent dynamic instabilities and noise. Here we realize the inversion of acoustic energy bands at a double Dirac cone and provide an experimental demonstration of an acoustic topological insulator. By manipulating the hopping interaction of neighbouring ’atoms’ in this new topological material, we successfully demonstrate the acoustic quantum spin Hall effect, characterized by robust pseudospin-dependent one-way edge sound transport. Our results are promising for the exploration of new routes for experimentally studying topological phenomena and related applications, for example, sound-noise reduction.

The exploration of support effect and interface effect on a homogeneous–heterogeneous hybrid CO2reduction photocatalytic system is deficient. Herein, we constructed oxides (WO3, Al2O3, SiO2, TiO2, and CuO) supported Co-based photocatalysts viaan incipient wetness impregnation method for visible-light driven CO2reduction with the assistance of a photosensitizer ([Ru(bpy)3]Cl2) and a sacrificial electron donor (triethanolamine) under mild conditions. Among them, the WO3supported Co-based photocatalyst (named 1Co/W) exhibited the highest CO generation rate (29.34 μmol h–1) with 81% selectivity and 0.73% apparent quantum yield. Moreover, the unit mass activity of surface Co components was up to 296.35 mmol gCo–1h–1. Experimental studies and characterization analyses indicated that the superior photocatalytic performance of 1Co/W benefited from the following aspects: (1) the well-matched band structure between 1Co/W and the photosensitizer for charge transfer and the suitable conduction band position for CO2conversion; (2) the tight interface structure between surface Co active species and WO3support accelerating the carrier migration kinetics and providing efficient cobalt active sites for CO2adsorption and activation; and (3) the dispersion and stabilization effect of WO3on surface Co active species.

On the smallest structural scale in the multi-scale structure composites, namely fiber scale, a numerical model was proposed for the analysis on the mechanical properties of unidirectional composites through the representative unit cell (RUC). The progressive method was used to simulate the failure behavior of fiber and matrix, and the debonding between fiber and matrix was characterized by the cohesive zone model (CZM). The failure strength of the unidirectional composite was predicted, and the influence of the interfacial strength on the mechanical behavior of unidirectional composite was discussed. It is shown that fiber dominates the failure strength of the material under the longitudinal load, whereas under the transverse load interfacial properties play an important role in the mechanical behavior of the material. The increase of the interfacial strength can significantly improve the capability of transverse compression and shear resistance.

Waveguides and resonators are core components in the large-scale integration of electronics, photonics and phononics, both in existing and future scenarios. In certain situations, there is critical coupling of the two components; i.e. no energy passes through the waveguide after the incoming wave couples into the resonator. The transmission spectral characteristics resulting from this phenomenon are highly advantageous for signal filtering, switching, multiplexing and sensing. In the present study, adopting an elastic-wave platform, we introduce topological insulator (TI), a remarkable achievement in condensed matter physics over the past decade, into a classical waveguide-ring-resonator configuration. Along with basic similarities with classical systems, a TI system has important differences and advantages, mostly owing to the spin-momentum locked transmission states at the TI boundaries. As an example, a two-port TI waveguide resonator can fundamentally eliminate upstream reflections while completely retaining useful transmission spectral characteristics, and maximize the energy in the resonator, with possible applications being novel signal processing, gyro/sensing, lasering, energy harvesting and intense wave–matter interactions, using phonons, photons or even electrons. The present work further enhances confidence in using topological protection for practical device performance and functionalities, especially considering the crucial advantage of introducing (pseudo)spins to existing conventional configurations. More in-depth research on advancing phononics/photonics, especially on-chip, is foreseen.A new, topologically empowered, planar waveguide-resonator system was demonstrated, exhibiting unique advantages over traditional designs.

This paper introduces a new method for the early detection of gastric cancer using a combination of feature extraction based on discrete wavelet transformation (DWT) for horizontal attenuated total reflectance–Fourier transform infrared spectroscopy (HATR–FT-IR) and classification using probability neural network (PNN). 344 FT-IR spectra were collected from 172 pairs of fresh normal and abnormal stomach tissue᾽s samples. After preprocessing, 5 features were extracted with DWT analysis. Based on the PNN classification, all FT-IR spectra were classified into three categories. The accuracy of identifying normal gastric tissue, early gastric cancer tissue and gastric cancer tissue samples were 100.00, 97.56 and 100.00%, respectively. This result indicated that FT-IR with DWT and PNN could effectively and easily diagnose gastric cancer in its early stages.