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The yolk–shell Co3V2O8 microspheres fabricated via the magneto-solvothermal method show a high specific capacity, outstanding rate performance, and long cycling life.

Co-based antiperovskite nitrides (CuNCo3/NF and CoN0.73Co3/NF) for overall water splitting are designed. An alkaline electrolyzer composed of CuNCo3/NF and CoN0.73Co3/NF has low cell voltage of 1.53 V at 10 mA cm−2 and maintains remarkable stability.

Ru/1T-MoS2 with excellent hydrogen evolution activity were designed by a two-step method of phase engineering and noble metal modification. The reasons behind its excellent hydrogen evolution activity were revealed experimentally and theoretically.

A schematic diagram showing the synthesis of the 1T-MoS2/Ti3C2Tx heterostructure and the fast charge–discharge networks in the heterostructure.

A one-pot synthesis of a well-matched and high-stability 1T-M0.71W0.29S2/Ti3C2Tx MXene heterostructure with high supercapacitor performance.

The polycrystalline CaBi2Nb2O9 ceramics with the addition of B2O3 can realize a large d33 of 20.4 pC N−1 and an ultra-high electrical resistivity of 1.4 × 107 Ω cm (at 600 °C), while still retaining a high TC of 958 °C.

MoS2/Ni3S2@C shows excellent sodium/potassium storage performance, which is due to carbon layer-confined heterostructure, creating more sodium/potassium storage sites, shortening ions diffusion path and relieving the volume change of the material.

Abundant vacancies in VS2 can unlock the transport of Zn2+ along the c-axis, and zinc dendrite growth can be effectively suppressed by an external weak magnetic field, achieving an excellent electrochemical performance.

We report the structure, dielectric, ferroelectric and piezoelectric properties of Cr-Mn co-doped (1-y)BiFe1-xCrxO3-yBaTi1-xMnxO3 (0≤x≤0.04, 0.2≤y≤0.27) ceramics. By varying both x and y, a series of samples near morphotropic phase boundaries exhibiting both high ferroelectric Curie temperature TC (∼580−643 °C) and relatively large piezoelectric constant d33 are constructed. Especially, the sample with y = 0.24 and x = 0.02 is found to show coexistence of high depolarization temperature Td (∼551 °C) and relatively large d33∼116 pC/N, superior to most of those of BiFeO3 based high-temperature piezoceramics reported previously. The enhanced ferroelectric TC in the Cr-Mn modified samples can be ascribed to the combined effects of large lattice distortion and high tetragonal phase content. These results demonstrate that constructing morphotropic phase boundaries via considering simultaneously the role of lattice distortion might be effective route to realize high-temperature and high piezoelectricity in BiFeO3-based systems.

For the construction and safe operation of major infrastructure in coastal cities, the impact of regional land subsidence that has occurred or is slowly proceeding deserves attention. Previous studies have mainly focused on the surrounding land subsidence caused during construction or operation, as well as the superposition effect of land subsidence caused by groundwater extraction. However, research on the different impacts of damage due to land subsidence in the construction and operation of urban infrastructure needs to be carried out according to the actual geological environmental conditions, reflected in parameters such as the soil properties and common loads. Numerical simulation cannot fully reflect the details of reality; however, it can avoid the influence of other conditions to focus on different factors influencing land subsidence and thus highlight the contribution of a single factor influencing land subsidence. Therefore, in this paper, we adopt field measurement data and carry out a numerical simulation analysis of different influencing factors. First, taking the Ningbo Jiangdong subsidence center (now located in Yinzhou District) as an example, area growth, cumulative subsidence and the occurrence and development of the subsidence rate of a typical urban subsidence funnel area are analyzed. Then, taking the Ningbo Chunxiao–Meishan area as an example, based on the physical and mechanical characteristics of the main soil layers in the coastal reclamation area, a numerical analysis of the self-weight/backfill and surcharge consolidation settlement of the soil layer (considering the water permeability/impermeability of the bottom surface) and a numerical analysis of the nonuniform settlement caused by pile foundation engineering are carried out. Finally, the Ximenkou–Gulou area is taken as the analysis object. Numerical simulation of metro tunnel pipeline deformation is carried out considering uniform/nonuniform settlement. The results show that the comprehensive prohibition of groundwater exploitation is beneficial to slow the land subsidence rate, while the sedimentation of silty clay in Layer 4 (muddy clay) is the largest among all the soil layers. Compared with uniform settlement, nonuniform settlement is more likely to cause connection failure between tunnel segments. The above research results can provide references for the prevention and control of land subsidence and thus the safe operation of major infrastructure.

As a promising cathode material of sodium-ion batteries, Na

Epitaxial La-doped BaSnO3 (BLSO) thin films were fabricated on a SrTiO3 (100) substrate by a cost-efficient and scalable solution deposition method. Microstructures and optoelectronic properties of...

A facile chemical solution deposition method was used to prepare La1−xAgxMnO3 thin films with 0.1 ≤ x ≤ 0.3 on LaAlO3 (001) single-crystal substrates. It was observed that the prepared thin films were grown epitaxially on the substrates with the epitaxial relationships of La1−xAgxMnO3(001) ||LaAlO3 (001) and La1−xAgxMnO3[110]||LaAlO3[110]. The lattice constant was decreased firstly and then saturated with doping. Both the ferromagnetic and semiconductor-metallic transition temperatures were firstly enhanced and then tended to saturate with Ag doping. The La0.85Ag0.15MnO3 showed the highest ferromagnetic transition temperature of 281 K and semiconductor-metallic transition temperature of 300 K. The results will provide a facile method to deposit epitaxial Ag-doped LaMnO3 thin films with potential room temperature applications.

As a prominent platform possessing the properties of superconductivity (SC) and charge density wave (CDW), transition-metal dichalcogenides (TMDCs) have attracted considerable attention for a long time. Moreover, extensive efforts have been devoted for exploring the SC and/or the interplay between SC and CDW in TMDCs in the past few decades. Here, we systematically investigate the electronic properties and structural evolution of 1T-TaSe2 under pressure. With increasing pressure, pressure-induced superconductivity is observed at ∼2.6 GPa. The superconductive transition temperature (Tc) increases with the suppression of the CDW state to the maximum value of ∼5.1 K at 21.8 GPa and then decreases monotonously up to the highest pressure of 57.8 GPa. 1T-TaSe2 transforms into a monoclinic C2/m structure above 19 GPa. The monoclinic phase coexists with the original phase as the pressure is released under ambient conditions and the retainable superconductivity with Tc = 2.9 K is observed in the released sample. We suggest that the retained superconductivity can be ascribed to the retention of the superconductive high-pressure monoclinic phase in the released sample. Our findings demonstrate that both the structure and CDW order are related to the superconductivity of TaSe2.

The nodal-line semimetals have recently gained attention as a promising material due to their exotic electronic structure and properties. Here, we investigated the structural evolution and physical properties of nodal-line semimetal ZrSiSe under pressure via experiments and theoretical calculations. An isostructural electronic transition is observed at ∼6 GPa. Upon further compression, the original tetragonal phase starts to transform into an orthorhombic phase at ∼13 GPa and the two phases coexist until the maximal experimental pressure. By analysis of the electronic band structure, we suggest that the significant changes in the Fermi surface contribute to the occurrence of the isostructural electronic transition. The results provide a new insight into the structure and properties of ZrSiSe.

The demand for terahertz (THz) communication and detection fuels continuous research for high-performance of THz absorption materials. In addition to varying the materials and their structure passi...

Flexible ferroelectric memories, endowing with high data storage density, provide a chance for the next-generation wearable electronics. Here, flexible inorganic Mn-doped BiFeO3 thin films were directly integrated on fluorophlogopite mica (F-Mica) substrates by an easy and low-cost all solution chemical solution deposition (AS-CSD) route. The integration of LaNiO3 buffer layer can improve the film surface density and uniformity. The flexible characteristic can be achieved by reducing the thickness of F-Mica substrates for the ferroelectric thin films. In contrast to BiFe0·93Mn0·07O3/LaNiO3/Si thin film deposited on rigid substrates (Si), the BiFe0·93Mn0·07O3/LaNiO3/F-mica fabricated on F-Mica show better ferroelectric performances due to the improved crystal growth and less defects. More importantly, the obtained BiFe0·93Mn0·07O3/LaNiO3/F-mica ferroelectric thin films still show large remnant polarization of Pr ∼64 μC/cm2 (deterioration of ∼7.2%), good antifatigue properties up to 1.2 × 108 cycles and outstanding retention behaviors for 1.6 × 104 s after continuous bending. This work will provide a feasible route to fabricate flexible inorganic ferroelectric thin films through low-cost solution method and show attractive comprehensive performances in next-generation wearable smart devices.

BiFeO3 as a type of single-phase room temperature multiferroic materials has aroused intensive investigations in recent years. Construction of porous BiFeO3 thin films is helpful for integration of other materials with desirable functionalities. Here, epitaxial BiFe0.93Mn0.07O3 (001) thin films were prepared on SrRuO3-buffered LaAlO3 (001) single crystal substrates by an all-solution chemical solution deposition, which is beneficial for large area thin film fabrication with low cost. Through addition of F-127 copolymer into the precursor solution, pores can be effectively introduced in BiFe0.93Mn0.07O3 (001) thin films while the epitaxy can be maintained. The amount of pores is gradually increased with increasing of the F-127 addition. The leakage current density is not obviously changed and the conduction mechanism can be well fitted through Ohmic behavior. Electric field dependent polarization hysteresis loops can be effectively maintained and the room temperature magnetic moment is obviously improved with the introduction of pores in epitaxial BiFe0.93Mn0.07O3 (001) thin films. The results will provide a facile route to fabricate large area epitaxial porous BiFeO3 thin films as an effective template for integration of other materials to realize desirable functionalities.

We investigate the influences of W/Ni co-doping on the structural, magnetic, electrical, and optical properties of four-layered Aurivillius Bi5FeTi3O15 ceramics. All the specimens can be indexed with the orthorhombic structure and the space group of A21am. The incorporation of W/Ni significantly promotes the grain’s growth and compactness. Compared with the antiferromagnetic state in pure sample, a weak room-temperature ferromagnetic state is found in the doped samples. The dielectric relaxations in samples with x ≤ 0.1 follow with Vogel–Fulcher relation and can be ascribed to the fluctuation behavior of local polarization, whereas the dielectric relaxation in sample x = 0.15 obeys well Arrhenius law and is due to the localized hopping process of electrons. The piezoelectric measurements indicate that the composition x = 0.05 represents the largest d33 value of 14pC/N at room temperature, which can be attributed to the optimal conductivity. In addition, all the compositions have two absorption edges with the direct inter-band transition due to the electron excitation from the hybridized Bi 6s + O 2p + Fe t2g valence band to Fe eg and Ti 3d conduction bands.

A backward diode consisting of all nondegenerate and transparent semiconducting oxides (TSOs) offers promising opportunities for designing multifunctional electronic devices. In this letter, we report the backward diode rectifying behavior in the nondegenerate AgCrO2/In2O3 p-n heterojunction. Both AgCrO2 and In2O3 films are transparent. The decrease of grain boundary in the In2O3 film can improve the backward diode rectifying performance. The optimized AgCrO2/In2O3 heterojunction exhibits a very high reverse rectification ratio that exceeds 103 along with a small tunneling current onset voltage. The backward diode rectifying behavior originates from the electron band-to-band tunneling (BTBT) current in the reverse voltage region, which is induced by type-III band alignment. This study will pave the way for achieving transparent backward diodes by using all nondegenerate TSOs p-n heterojunctions.

Introducing ferromagnetism in two-dimensional (2D) carbon-based materials, which contain only s–p electrons, is of essential and practical importance. Here, room-temperature ferromagnetism is reali...

Hexagon-like MAX-phase V4AlC3 single crystals grown by a high-temperature flux method were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDX). We report, for the first time, the first-order Raman spectra (RS) of V4AlC3 single crystals experimentally and theoretically. Via the combination of the results of thermogravimetric analysis, differential scanning calorimetry, XRD, FE-SEM, and EDX, the oxidation performance and mechanism of V4AlC3 single crystals between 300 and 1473 K in air were clarified. Importantly, we carefully investigated the room-temperature corrosion behaviors of V4AlC3 single crystals in concentrated acids [HCl, H2SO4, hydrofluoric acid (HF), and HNO3] and alkalis (NaOH and KOH). V4AlC3 single crystals are stable in concentrated HCl, H2SO4, and NaOH but unstable and even dissolved completely in concentrated KOH and HNO3. In particular, our XRD, RS, FE-SEM, and EDX results have confirmed that HF can dissolve the Al layers of V4AlC3 single crystals but cannot corrode V4C3 layers at room temperature, which eventually led to the formation of macroscopic V4C3Tx MXene. This reported approach of macro-sized V4C3Tx MXene can be adapted for obtaining other macroscopic MXenes and will inspire plenty of theoretical and experimental investigations to explore their intrinsic nature and applications, especially for electronic and photonic applications.

Transparent conducting (TC) donor-doped In2O3 thin films are the critical components in photovoltaic, display and solid-state lighting fields. In2O3-based TC films with high carrier mobility are required for reducing the power consumption of devices. Meanwhile, a high near-infrared (NIR) transparency can significantly improve the power conversion efficiency in solar cells. Here, W-doped In2O3 thin films with high carrier mobility and NIR transparency were obtained through a facile solution process, which is suitable for large-scale thin film fabrication. The effects of W concentration (0.3 at% to 0.7 at%) on the microstructures, electrical and optical properties of In2O3 thin films are investigated in detail. It is found that the 0.5% W-doped In2O3 thin film exhibits high carrier mobility of 23 cm2 V−1 s−1 at a carrier concentration of 5.02 × 1020 cm−3, showing a high NIR transmittance over 82% and low sheet resistance of 32 Ω/sq. The solution processed W-doped In2O3 thin films with low sheet resistance and high NIR transparency can be potentially used as transparent electrodes for solar cells.