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The acoustic catalytic degradation of methylene blue (MB) was studied using silicon carbide (SiC) nanowires and commercial TiO2 (P-25). SEM images show that the average diameter of SiC nanowires is less than 500 nm and the length is up to tens of microns. XRD patterns and FTIR spectra confirmed the high purity of SiC in the catalyst. The catalytic performance of the two catalysts is better under alkaline conditions. The Kapp values (pseudo-first-order kinetics) of the synergistic effects of ultrasonic treatment and adsorption processes using SiC and TiO2 are 1.36 and 1.31 times the sum of the Kapp values of the two separate processes, respectively. This finding indicates that acoustic catalysis can improve the photocatalytic performance of SiC and TiO2 on MB. Compared with TiO2, SiC nanowires exhibit better acoustic catalytic performance, and hydroxyl radicals are more significant in the acoustic catalytic degradation of SiC to MB. Meanwhile, hydroxyl radicals play a leading role in the degradation process of MB. [ABSTRACT FROM AUTHOR]

Diatomaceous earth has been used as a nonorganic carrier to prepare a sodium humate modified diatomaceous space using the sol‐gel method. X‐ray diffraction, field emission scanning electron microscopy, transmission electron microscope, the Brunauer–Emmett–Teller (BET) method, and other methods were used to characterize its physio‐chemical properties. The effects of sodium humate/diatomite on the pH of tetracycline in water, the dosage of adsorbent, and pollutant temperature on the adsorption effect were studied. The results show that after alkali modification, the porous structure of diatomite remains undamaged, and the specific surface area of the modified sample is increased to 12.712 m2/g, and the average pore diameter is reduced to 146.19 nm. Adding 20‐mg sodium humate/diatomite into 100‐mL tetracycline wastewater with an initial concentration of 20 mg/L, and pH of 5 at a temperature of 55°C, the adsorption capacity reaches 75.1 mg/L, and the removal rate reaches 78.3%. The quasi‐second‐order kinetic model was fitted by regression and found to have R2 > 0.99, indicating that the adsorption process was one of surface adsorption. It is a process that involves initially rapid adsorption and then slowly reaching equilibrium. As an adsorption thermodynamics model, the Temkin, Redlich‐Peterson and Koble‐Corrigan models can explain humic acid sodium/diatomite behavior in the adsorption of tetracycline in water (each with R2 ≥ 0.99), and the effects of surface behavior in multilayer adsorption and electrostatic attraction on uneven heterogeneous adsorption. [ABSTRACT FROM AUTHOR]

Resistive random access memory (RRAM) crossbar arrays require the highly nonlinear selector with high current density to address a specific memory cell and suppress leakage current through the unselected cell. 3D monolithic integration of RRAM array requires selector devices with a small footprint and low‐temperature processing for ultrahigh‐density data storage. Here, an ultrathin two‐terminal n‐p‐n selector with 2D transition metal dichalcogenides (TMDs) is designed by a low‐temperature transfer method. The van der Waals contact between transferred Au electrodes and TMDs reduces the Fermi level pinning and retains the intrinsic transport behavior of TMDs. The selector with a single type of TMD exhibits a trade‐off between current density and nonlinearity depending on the barrier height. By tuning the Schottky barrier height and controlling the thickness of p‐type WSe2 in MoS2/WSe2/MoS2 n‐p‐n selector for a punch‐through transport, the selector shows high nonlinearity (≈ 230) and high current density (2 × 103 A cm−2) simultaneously. The n‐p‐n selectors are further integrated with a bipolar hexagonal boron nitride memory and calculate the maximum crossbar size of the 2D material‐based one‐selector one‐resistor according to a 10% read margin, which offers the possible realization of future 3D monolithic integration. [ABSTRACT FROM AUTHOR]