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Information processing with optoelectronic devices provides an alternative way to efficiently process hybrid optical and electronic signals. Ferroelectric field‐effect transistors (FeFETs) can effectively respond to external optical and electrical stimuli by modulating their polarization states. Here, a 2D FeFET is demonstrated by the epitaxial growth of high‐quality 2D bismuth layered oxyselenide (Bi2O2Se) films on PMN‐PT(001) ferroelectric single‐crystal substrates. Upon switching the polarization direction of PMN‐PT, the authors realize in situ, reversible, and nonvolatile manipulation of the resistance of Bi2O2Se thin film (≈877%). The device simultaneously exhibits a polarization‐dependent photoresponse through visible light (λ = 405 nm) and infrared light (IR, λ = 980 nm) illumination. Combining optical stimuli with ferroelectric gating, it is demonstrated that the devices not only show nonvolatile memory and optoelectronic responses, but also show coincidence detection of visible and IR light. This work holds great potential in constructing new multiresponse and multifunction 2D‐FeFETs. [ABSTRACT FROM AUTHOR]

NiO–Ni composite films were heteroepitaxially grown on (111)-oriented ferroelectric 0.31Pb(In1/2Nb1/2)O3-0.35Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PIN-PMN-PT) single-crystal substrates by pulsed laser deposition. The NiO films prepared in high vacuum are n-type conducting and possess room-temperature ferromagnetism, which originates from oxygen vacancies and the presence of the second Ni phase, respectively. Taking advantage of the electric-field-induced ferroelectric polarization charges, we realized in situ reversible and nonvolatile modulation of both the electrical resistance and magnetism of the film. A relative resistance change of ∼470% is obtained at room temperature, while an appreciable magnetization change of ∼15% was achieved at 50 K by switching the polarization states of PIN-PMN-PT. The coexistence of charge-density-tunable electronic and magnetic properties of NiO–Ni/PIN-PMN-PT heterostructures may provide a strategy to design charge-mediated multiferroic devices for nonvolatile memory and spintronic applications. [ABSTRACT FROM AUTHOR]

We report the structural, dielectric, ferroelectric and magnetic properties of (1- x)BiFe 0.95 Ga 0.03 Mn 0.02 O 3 − x BaTiO 3 (BFGMO− x BTO) lead-free ceramics. Structural characterizations demonstrate that the BFGMO forms single-phase solid solutions with the BTO within the doping level of x = 0.3–0.65. With increasing the content of BTO the dielectric constant and ferroelectric Curie temperature shift towards lower temperatures, exhibiting relaxor-like ferroelectric behaviors. Moreover, the remnant polarization reaches the maximum value of 2 P r ~27.67 μC/cm2 at x = 0.35 near the morphotropic phase boundary. At room temperature, remnant magnetization increases - to the maximal value of 2 M r ~0.584 emu/g at x = 0.45, which is attributed to local lattice distortion and destruction of the spiral antiferromagnetic spin structure upon the doping of BTO. The coexistence of ferroelectric and ferromagnetic performance at room temperature makes the environment-friendly BFGMO− x BTO ceramics potential candidate for multiferroic device applications. [ABSTRACT FROM AUTHOR]

Electric-field switchable multilevel nonvolatile resistance states are achieved at room temperature in Bi0.93Sb0.07/0.71Pb(Mg1/3Nb2/3)O3-0.29PbTiO3(111) (PMN-0.29PT) heterostructures. During the initial poling of the PMN-0.29PT, the variation of the resistance of the Bi0.93Sb0.07 film with the electric field tracks the variation of the electric-field-induced in-plane strain of the PMN-0.29PT effectively, revealing that the resistance switching is dominated by the ferroelectric-domain-switching-induced lattice strain but not the domain-switching-induced polarization charges. A relative resistance change ΔR/R ∼ 7% at 300 K and up to ∼10% at 180 K were achieved near the coercive field EC of the PMN-0.29PT(111) substrate. At least five stable resistance states with good endurance properties could be obtained at room temperature by precisely controlling the electric-field pulse sequence as a result of the nonvolatile remnant strain transferring from the PMN-0.29PT to the film, providing a simple and energy efficient way to construct multistate resistive memory. [ABSTRACT FROM AUTHOR]

Superconducting thin films of FeSe 0.5 Te 0.5 are epitaxially grown on piezoelectric 0.71Pb(Mg 1/3 Nb 1/2 )O 3 -0.29PbTiO 3 (PMN-PT) single-crystal substrates. Upon the application of an electric field to the PMN-PT along the thickness direction the superconducting properties of the FeSe 0.5 Te 0.5 films, such as the normal-state resistance, superconducting phase transition temperature, upper critical field, critical current, and coherence length are in situ modified via the ferroelectric polarization rotation, converse piezoelectric effect, and structural phase transition of the PMN-PT. Our findings demonstrate that the combination of superconducting thin films with piezoelectrically active PMN-PT offers a promising approach for exploring the intrinsic lattice strain effects of iron-based superconducting systems. [ABSTRACT FROM AUTHOR]

Hydrogenation of silicon tetrachloride(STC) in the presence ofsilicon was investigated both thermodynamically and experimentally.The thermodynamic results revealed that the reaction is thermodynamicallyconstrained and the STC equilibrium conversion is nearly temperature-independentbut increases with increasing pressure and H2/STC feedratio. Trichlorosilane (TCS) was calculated to be the dominant product,with trace amounts of dichlorosilane (DCS) and HCl as feasible byproducts.Experimental tests were conducted in a fixed-bed reactor loaded withsilicon. The results indicated that the reaction is kinetically restrictedin the absence of a catalyst. Adding CuCl to the silicon mass bedwas found to result in a dramatic increase in the STC conversion,and Cu3Si was determined to be the active species. In allof the tests runs, TCS was determined to be the dominant product,and the STC reaction rate was found to increase markedly as the temperatureand STC partial pressure increased but not to depend on the siliconparticle size. [ABSTRACT FROM AUTHOR]

SrIrO3 (SIO) thin films were epitaxially grown on (001)-oriented 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) single-crystal substrates. Upon applying electric fields to the piezoelectric PMN-PT along the thickness direction, the electronic transport properties of SIO films can be in situ tuned and modulated by non-180° ferroelectric domain rotation-induced strain, piezoelectric strain, and rhombohedral-to-tetragonal structural phase transition-induced strain in the PMN-PT layer, respectively. Moreover, the weak negative magnetoresistance (MR) of the 60-nm SIO films could be modified by applying an electric field to the PMN-PT layer. At T = 2 K, upon the application of E = 4 kV/cm to the PMN-PT, MR at H = 9 T is reduced by 14.2% as compared to that under zero electric field, indicating in-plane compressive strain-induced suppression of the influence of quantum corrections to the conductivity in the SIO film. These results demonstrate that the electric-field controllable lattice strain is a simple approach to get insight into the strain-property relationships of 5d iridate thin films. [ABSTRACT FROM AUTHOR]

The authors inadvertently used the unit "Oersted (Oe)" of the magnetic field instead of the correct unit "Tesla (T)." The sentence "On one hand, the greater difference of I M i SB S sb can be ascribed to the larger absolute difference in carrier density (7.6 × 10 SP 18 sp cm SP -3 sp ) between the two polarization states (Fig. S3, supplementary material), as compared with the corresponding value at 300 K (1.19 × 10 SP 18 sp cm SP -3 sp )." should be corrected as "On one hand, the greater difference of I M i SB S sb can be ascribed to the larger absolute difference in carrier density (7.6 × 10 SP 22 sp cm SP -3 sp ) between the two polarization states (Fig. [Extracted from the article]

• The BFGMO–BTO film is successfully prepared by pulsed laser deposition method. • The structure and magnetic properties highly depend on the oxygen pressure. • The electric field used to switch ferroelectric domains increases with the film thickness. • The work contributes to finding a route to achieve more excellent room-temperature multiferroic films. 0.55BiFe 0.95 Ga 0.03 Mn 0.02 O 3 –0.45BaTiO 3 (BFGMO–BTO) thin films have been epitaxially grown on (0 0 1)-oriented Nb-doped SrTiO 3 (NSTO) single-crystal substrates by the pulsed laser deposition. X-ray diffraction, selected area electron diffraction, magnetic hysteresis loop, and piezoresponse force microscopy results show that the structural and magnetic properties of the BFGMO–BTO epitaxial films can be progressively tuned by the oxygen pressure (P O 2 ) during film deposition. The films prepared at P O 2 = 5 Pa phase separated into BFGMO and BTO phases, however, with increasing P O 2 to 20 Pa the films evolve from two phases to single phase with the best crystalline quality, largest saturation magnetization, lowest coercive field and relatively easy-switchable ferroelectric domains. [ABSTRACT FROM AUTHOR]

Currently, the mechanical vapor recompression (MVR) system is extensively used for single salt separation, but the relevant research on mixed salt system treatment is still in initial stage. As a very common salt solution system, sodium chloride–potassium chloride–water system can be readily found in many processes. It is no doubt of great significance to separate their crystals from the mixed solution in an efficient and environmentally friendly way. Therefore, with the aid of Aspen Plus software, this study aims to design an MVR evaporation system capable of treating sodium chloride–potassium chloride–water system. Subsequently, the analysis about the start‐up schemes and some influencing factors in the steady‐state operation are carried out, so as to provide some guidance and reference for the future technical route to separate mixed salt system with low energy consumption. [ABSTRACT FROM AUTHOR]

We synthesized In 3+ -doped Ba 0.85 Ca 0.15 TiO 3 :Er 3+ /Yb 3+ / x In 3+ lead-free ferroelectric ceramics that possess strong ferroelectricity and excellent upconversion luminescence under the excitation of 980 nm. With increasing x from 0, the green and red emission intensity increases and reaches the maximum at x =1.5% mol, then decreases slightly with further increase in x . For the x =1.5% sample the green emission intensity at 550 nm is ∼10 times larger than that of In 3+ undoped samples. Such a large In 3+ doping-induced enhancement of the luminescence is unprecedented for perovskite ferroelectrics. Based on the ultraviolet-visible-near infrared absorption spectra, the variation of the luminescence intensity with the In 3+ content was discussed. [ABSTRACT FROM AUTHOR]

TheCuCl-catalyzed hydrogenation of silicon tetrachloride (STC)in the presence of silicon was conducted in a fixed-bed reactor. Thesolid mass from different reaction stages was collected and characterizedusing X-ray diffraction (XRD) and scanning electron microscopy coupledwith energy-dispersive X-ray spectroscopy (SEM-EDX). The characterizationresults were used to develop a novel reaction mechanism. This mechanismis remarkable in that the Cu–Si surface species acted as botha catalyst and a solid reactant and could be regenerated via Cu diffusioninto the bulk silicon phase. Different kinetic models were formulatedby employing the Langmuir–Hinshelwood (L–H) and Eley–Rideal(E–R) approaches. Model discrimination was used to select akinetic model based on the E–R mechanism, in which the surfacereaction between the adsorbed STC and gas-phase H2overthe Cu3Si active sites was assumed to be the rate-determiningstep (RDS). The kinetic parameters were estimated using nonlinearregression, and the model predictions were in good agreement withthe experimental data. [ABSTRACT FROM AUTHOR]

Thispaper presents a reactive distillation column for the catalyticdisproportionation of trichlorosilane to silane which includes threeconsecutive reversible reactions with a thermodynamic conversion tosilane as low as 0.2% and is of no practical significance using theconventional reactors. This reaction system is however characterizedby a large distinction in the boiling points of the components, whichmakes the reactive distillation extremely favored. Nevertheless, thenormal reactive distillation column possesses the shortage of highrefrigeration requirement as the standard boiling point of the overheadproduct silane is −112 °C. A novel reactive distillationcolumn with intercondensers placed within has been simulated usingAspen Plus package for a feasible alternative to alleviate this drawback.The calculated results show that a reduction in the refrigerationload of more than 97% can be obtained when one intermediate condenseris inserted between the rectifying and reaction zones, and that anothernormal intermediate condenser equipped within the reaction sectioncan further decrease the condensation requirement of the first intermediatecondenser by 50%. Effects of the configuration parameters and operationalconditions have also been investigated for optimal design and operationof the proposed reactor. [ABSTRACT FROM AUTHOR]

We epitaxially grew 7 mol. % Nd-doped BaSnO3 (NBSO) thin films on double-side polished SrTiO3 (001) single-crystal substrates and optimized the oxygen pressure (PO2), substrate temperature (TS), and film thickness (t) to achieve excellent structural, optical, and electrical performance. By keeping TS (=800 °C) constant, NBSO films prepared at PO2 = 10 Pa show the best crystallization, yielding a full-width at half-maximum (FWHM) of the x-ray diffraction rocking curve of 0.079° and exhibiting a room-temperature resistivity (ρ) of ∼1.85 mΩ cm and a volume carrier density (n) of ∼8.5 × 1020/cm3. By keeping PO2 (=10 Pa) constant, the room-temperature ρ of NBSO films could be reduced to as low as 0.5 mΩ cm by increasing TS from 700 to 825°; meanwhile, the volume carrier density and mobility show the maximum of 5.04 × 1020/cm3 and 24.9 cm2/Vs, respectively, for TS = 825 °C. For all as-grown NBSO thin films, the optical transmittance in the visible wavelength region is larger than 80%. The optimized comprehensive properties of the NBSO films with FWHM = 0.11°, ρ = 0.5 mΩ cm, μ = 24.9 cm2/Vs, and T > 80% are superior to those of other rare-earth and 4d- and 5d-transition metal-doped BaSnO3 thin films. [ABSTRACT FROM AUTHOR]

• In situ reversible tuning of resistance is achieved in LaMnO 3 /PMN-PT(0 1 1) structure. • Non-180° domain switching-induced strain causes nonvolatile resistance tuning. • In-plane tensile stain contributes to the weakened magnetization. The electric-field control of resistance change (Δ R / R) and magnetic properties has been investigated in the LaMnO 3 (LMO)/0.71Pb(Mg 1/3 Nb 2/3)O 3 -0.29PbTiO 3 (PMN-PT)(0 1 1) heterostructure. When the unipolar electric field (E) increases beyond the coercive field of PMN-PT, the Δ R / R vs E curve transforms from a loop-like behavior to a butterfly-like one. The electric-field-induced non-linear strain effect in the PMN-PT substrate realizes the modulation between low and high resistance states at room temperature. Moreover, different freezing temperatures of the LMO film are observed as the PMN-PT substrate is in the fully negative (P r -) and partially positive (P r / / ) polarization states. The observation of less magnetization for P r / / state than that for P r - state indicates that the in-plane tensile strain is beneficial to the Jahn-Teller distortion. [ABSTRACT FROM AUTHOR]