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The structure and electronic and spintronic properties of two-dimensional (2D) ternary compounds ABC (A = Sb, Bi; B = Se, Te; C = Br; I) monolayers are investigated using the first-principles method. The ABC monolayers possess typical Janus structures with a considerable potential gradient normal to the surface, inducing intrinsic Rashba spin splitting (RSS) at the conduction band minimum near the

Combined with first-principles calculations and semiclassical Boltzmann transport theory, Janus {\alpha}-STe2 and {\alpha}-SeTe2 monolayers are investigated systematically. Janus {\alpha}-STe2 and {\alpha}-SeTe2 monolayers are indirect semiconductors with band gaps of 1.20 and 0.96 eV. It is found they possess ultrahigh figure of merit (ZT) values of 3.9 and 4.4 at 500 K, much higher than that of the pristine {\alpha}-Te monolayer (2.8). The higher ZT originates from Janus structures reduce lattice thermal conductivities remarkably compared with pristine {\alpha}-Te monolayer. The much higher phonon anharmonicity in Janus monolayers leads to significant lower lattice thermal conductivity. It is also found electronic thermal conductivity can play an important role in thermoelectric efficiency for the materials with quite low lattice thermal conductivity. This work suggests the potential applications of Janus {\alpha}-STe2 and {\alpha}-SeTe2 monolayers as thermoelectric materials and highlights Janus structure as an effective way to enhance thermoelectric performance.

We summarize the strategies for improving the waterproofness of Mn4+-doped fluoride phosphors, including organic coating, inorganic heterogeneous/homogeneous coating, surface deactivation, preparation of single crystal phosphor, and other methods.

A hydrogen processing strategy is developed to enable bulk LaNi5 to attain high activity and long‐term stability toward the electrocatalytic oxygen evolution reaction (OER). By a combination of in situ Raman and quasi in situ X‐ray absorption (XAS) spectra, secondary‐electron‐excited scanning transmission electron microscopy (STEM) patterns as well as the Rietveld method and density functional theory (DFT) calculations, it is discovered that hydrogen‐induced lattice distortion, grain refinement, and particle cracks dictate the effective reconstruction of the LaNi5 surface into a porous hetero‐nanoarchitecture composed of uniformly confined active γ‐NiOOH nanocrystals by La(OH)3 layer in the alkaline OER process. This significantly optimizes the charge transfer, structural integrity, active‐site exposure, and adsorption energy toward the reaction intermediates. Benefiting from these merits, the overpotential (322 mV) at 100 mA cm−2 for the hydrogen‐processed OER catalyst deposited on nickel foam is reduced by 104 mV as compared to the original phase. Notably, it exhibits remarkable stability for 10 days at an industrial‐grade current density of more than 560 mA cm−2 in alkaline media.

The utilization of clean hydrogen energy is becoming more feasible for the sustainable development of this society. Considering the safety issues in the hydrogen production, storage, and utilization, a sensitive hydrogen sensor for reliable detection is essential and highly important. Though various gas sensor devices are developed based on tin oxide, tungsten trioxide, or other oxides, the relatively high working temperature, unsatisfactory response time, and detection limitation still affect the extensive applications. In the current study, an amorphous tungsten trioxide (a-WO

Vacancy engineering is deemed as one of the powerful protocols to tune the catalytic activity of electrocatalysts. Herein, Se vacancy with charge polarization is created in the NiSe2 structure NiSe2 VSe via a sequential phase conversion strategy. By a combined analysis of the Rietveld method, transient photovoltage spectra TPV , in situ Raman and density functional theory DFT calculation, it is unequivocally discovered that the presence of charge polarized Se vacancy is beneficial for stabilizing the structure, decreasing the electron transfer kinetics, as well as optimizing the free adsorption energy of reaction intermediate during two electron oxygen reduction reaction 2e amp; 8722; ORR . Benefiting from these merits, the as prepared NiSe2 VSe delivered the highest selectivity of 96 toward H2O2 in alkaline media, together with a selectivity higher than 90 over the wide potential range from 0.25 to 0.55 V, ranking it in the top level among the previously reported transition metal based electrocatalysts. Most notably, it also displayed admirable stability with only a slight selectivity decay after 5000 cycles of accelerated degradation test ADT

In image super-resolution task, the existing convolutional neural network methods proceed to increase the number of network layers and filters to achieve better performance. Nevertheless, such approaches not only lead to a dramatic increase in network parameters, but also restrict the practical application of super-resolution methods. In order to address this problem, we propose a lightweight model called Channel Rearrangement Multi-Branch Network (CRMBN) for super-resolution of single images. Specifically, we design a channel rearrangement algorithm based on the total variation of the feature maps. It is inspired by the fact that the feature maps with high total variation contain more high-frequency details, which are valuable for super-resolution reconstruction. Therefore, for the super-resolution networks, the more feature maps with high total variation, the better performance of reconstruction. The rearranged channels are divided into two groups, one with high total variation and the other with the opposite. In order to reduce the parameters while mining for more details, we send the features with low total variation to the deep network. Finally, high total variation features and deep features are fused to reconstruct high-resolution image. The experimental results show that compared with other lightweight models, the proposed method can offer a favorable improvement in terms of PSNR and SSIM.

The stabilization of semiconductor against photocorrosion has become one of the most essential targets in photoelectrochemical water splitting. Herein, a research of three mixing enhancement strategies of WO3/BiVO4 heterojunction, W doping, and oxygen vacancy formation can be made to incorporate into such a nanostructure during the preparation of BiVO4 in terms of PEC performance improvement. The WO3 layer not only facilitated the electron transfer, but importantly, was used as a diffusion source for W doping which brought oxygen vacancies on the bulk material. Moreover, the introduction of different W doping profiles,- bottom, middle, and top, all electrodes exhibited a photo-activation character with the improved photocurrent and the negative shift of onset potential. The bottom W doping led to the most notable enhancement in charge separation efficiency on BiVO4 electrode, which yielded the close photocurrent densities of ∼4.4 mA cm−2 at 1.23 VRHE under front and back 1 sun illumination. More importantly, the cocatalyst-free W:BiVO4-Ov photoanode present a favorable stability during 25 h test applied at 1.0 VRHE. By experimental and theoretical arguments, it demonstrated that the multiple collaborative strategies shed light on designing efficient and stable photoelectrodes for solar energy conversion.