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Materials with a low coefficient of thermal expansion (CTE) are extremely demanded in many fields, varying from microelectronics to space technology. Here we report a novel method to achieve low CTE, which differs essentially from the conventional way that uses additives with negative thermal expansion (NTE) to compensate for the positive CTE of the matrix. The stoichiometric Hf

Bismuth ferrite (BiFeO

An excitonic insulating (EI) state is a fantastic correlated electron phase in condensed matter physics, driven by screened electron-hole interaction. Ta

The phase-controlled synthesis of metallic and ambient-stable 2D MX2 (M is Mo or W; X is S) with 1T octahedral coordination will endow these materials with superior performance compared with their semiconducting 2H coordination counterparts. We report a clean and facile route to prepare 1T-MoS2 and 1T-WS2 through hydrothermal processing under high magnetic fields. We reveal that the as-synthesized 1T-MoS2 and 1T-WS2 are ambient-stable for more than 1 year. Electrochemical measurements show that 1T-MoS2 performs much better than 2H-MoS2 as the anode for sodium ion batteries. These results can provide a clean and facile method to prepare ambient-stable 1T-phase MX2.

The phase-controlled synthesis of metallic and ambient-stable 2D MX

For applications in portable electronics and miniaturized energy storage devices, MXene films derived from MXene inks can be provided as promising electrodes for thin film supercapacitors. Hence, to improve the areal capacitance of MXene films is necessary for pursuing high energy density. Introduction of transitional metal oxides (TMOs) layers into MXene electrodes obviously enhances the areal capacitance since of the extra pseudocapacitance induced by the surface/near surface redox reactions. The severe oxidation of MXene in combination with TMOs, however, hinders the effective improvements in capacitance. Laser crystallization process can effectively alleviate the oxidation of MXene when TMOs is prepared due to the high temperature localization and ultrafast reaction speed. Here, a sandwich-like MXene/Fe3O4/MXene film with a porous Fe3O4 layer is successfully prepared on a flexible Ni tape, showing an excellent electrochemical performance. In 1 M Li2SO4 aqueous electrolyte, the sandwich-like electrode demonstrates 46.4 mF cm−2 at the current density of 0.5 mA cm−2. The as-constructed symmetric all-solid-state device displays an energy density of 0.970 μWh cm−2 at a power density of 0.176 mW cm−2 along with a good cycling stability. This work opens up a new opportunity for modifying MXene films as electrodes for high-performance thin film supercapacitors.

A-site-ordered perovskites LaMn3Rh4O12 and La0.8Ca0.2Mn3Rh4O12 were prepared by using high-pressure and high temperature method. Structural and BVS analyses suggest that the valence states of Mn and Rh ions are both +3 in LaMn3Rh4O12. Partial Ca-doping introduced some Mn4+ ions, which are transferred to B site and leave some deficiencies at A′ site. Localized electrons of Mn and Rh ions induce a semiconducting behavior. Combined with the results of the first principles calculation, it is believed that the interaction between high spin Mn3+ ions induce a G-type antiferromagnetism, while low spin Rh3+ ions have no magnetic contribution. And also, there is no interaction between Mn and Rh ions. The results confirm that non-Jahn-Teller distorted Mn4+ ion cannot occupy A′ site in the A-site-ordered perovskite, even partly.

Molybdenum diselenide (MoSe2) has been considered as a promising electrocatalyst for the hydrogen evolution reaction (HER), having great significance in the exploration of catalysts for green energy production. To obtain excellent electrocatalytic properties of MoSe2, the structural design of materials has become a commonly-used strategy. Hence, the combination of hexadecyl trimethyl ammonium bromide (CTAB) and polyethylene-polypropylene glycol (F68) was employed during hydrothermal process to modify the structure of MoSe2. Compared with using only one surfactant (CTAB or F68), MoSe2 catalyst represents better surface activity, more active sites and enhanced catalytic activity in the presence of dual surfactants. The as-prepared MoSe2-CTAB@F68 catalyst achieves an excellent HER activity with an overpotential of 189 mV versus the reversible hydrogen electrode (RHE) at a current density of 10 mA cm−2 and a low Tafel slope of 62 mV dec−1. Therefore, this work paves a way to prepare electrocatalysts with dual surfactants existence, which is greatly attractive for an optimizing electrocatalyst performance in a more efficient way.

The high-quality (111)-oriented pyrochlore oxide thin films Y2(Hf1-xIrx)2O7 (YHIO) were prepared by pulsed laser deposition. The bandgap values of Ir-substituted YHIO thin films for x = 0–0.5 range from 4.6 to 1.9 eV. Taking account of spin orbital coupling and correlation effect (U), the first-principles calculations based on density functional theory were used to intercept this variation. The theoretical results illustrate that the variation is attributed to the lower Ir 5d orbital in energy and stronger orbital hybridization between the oxygen 2p orbital and the Ir 5d orbital near the Fermi surface. These results suggest that we can widely modulate the bandgap through B-site chemical substitution based on the Y2Hf2O7 thin film.

We report the effects of chemical doping on thermoelectric properties of metal-based thermoelectric materials Sn 1− x M x CCo 3 ( M = Ag, In, Ge, Pb, Sb, Te, and Bi) with antiperovskite structure. Compared to parent compound SnCCo 3 , both Seebeck coefficient ( S ) and figure of merit ( ZT ) can be effectively enhanced by hole doping, while a decreased S and ZT appear in equivalent- and electron-doped SnCCo 3 . Among all the doped samples, the maximum ZT value of 0.045(1) is obtained in Sn 0.95 Ag 0.05 CCo 3 , which is about 50% larger than that of parent compound SnCCo 3 (ZT ∼ 0.03). This enhanced ZT is mainly attributed to the increased S induced by locally modified density of states near Fermi level. In addition, our optimized ZT value (∼0.045, at 235 K) is relatively large compared with other typical low-temperature thermoelectric materials.

Epitaxial SrRuO 3 (SRO) thin films have been prepared on (100), (110), and (111) LaAlO 3 substrates by chemical solution deposition method, and the microstructures as well as the properties are investigated. The SRO (110) thin films display much more denser, homogeneous and well-connected grains. All the derived SRO thin films show a metallic behavior with low room-temperature resistivity (mΩ·cm). All derived SRO films are ferromagnetic at low temperatures showing different Curie temperature due to the different residual stain, and the SRO (110) film has the largest magnetization and coercivity due to the enhanced morphology. These results will provide a low-cost route to fabricate epitaxial SRO thin films with different orientation.

Herein we systematically investigated the alloying effects on structural, magnetic, and electrical/thermal transport properties in MAX-phase Cr2−xMxGeC (M = Ti, V, Mn, Fe, and Mo). The alloying of M with the larger covalent radius than that of Cr increases lattice constants (a and c) as well as unit cell volume (V) of Cr2−xMxGeC, and vice versa. However, the c/a ratio monotonously decreases with increasing alloying level x, which is due to a larger change of a than that of c. The Pauli paramagnetic ground state of Cr2GeC is confirmed by magnetic measurements and low-temperature specific heat analysis. Interestingly, ferromagnetism can be introduced in Cr2−xMxGeC by doping magnetic elements (Mn and Fe) and non-magnetic elements (Ti and Mo), which may be due to a reconstruction of the Fermi surface caused by chemical doping. All our samples show a metal-like electrical transport behavior, and the residual resistivity ratio decreases with increasing alloying concentration, which are mainly attributed to the disorders induced by alloying. The change of electron specific heat coefficient is consistent with the change of density state of Fermi surface in Cr2−xMxGeC. In addition, solid-solution scattering is the dominant factor for the behavior of thermal conductivity k(T) in Cr2−xVxGeC, while enhanced phonon scattering induced by alloying is the decisive factor for the change of k(T) in Cr2−xMoxGeC. The positive Seebeck coefficient of Cr2−xVxGeC and Cr2−xMoxGeC may be close related to the decrease of structural anisotropy.

Liver injury is a major hindrance to the treatment of tuberculosis (TB) patients due to the primary side effects associated with anti-TB drugs. Several investigations have identified sensitive biomarkers for the early diagnosis of anti-TB drug-induced liver injury (ADLI), including the use of microRNAs (miRNAs/miRs). However, the association between miR-122/155 and ADLI remains unknown. Thus, the present study used reverse transcription-quantitative polymerase chain reaction to observe changes in tissue miR-122/155 expression levels during the course of liver injury in mice. Liver injury was induced by the administration of isoniazid (INH), a first-line anti-TB drug. miR-122/155 expression levels were quantified at seven time points throughout 1 day (0.25, 0.75, 1.5, 6, 12, 18 and 24 h) based on the pharmacokinetics of INH in mice. Notably, over the timecourse of INH-induced liver injury, the tissue miR-122 expression level significantly decreased at 0.25 h, which is the peak concentration time of INH, compared with the control group (P

Multiferroic BiFeO3 (BFO) thin films with a thickness larger than 400 nm are grown on solution-derived LaNiO3 coated Si substrates via chemical solution deposition. The prepared BFO/LaNiO3/Si thin films are strongly (00l)-oriented with a distorted rhombohedral structure of R3c symmetry. The effects of the annealing temperature within the temperature range of 500–650 °C on the microstructures and properties are investigated. With an annealing temperature increasing to 600 °C, the (00l) orientation is enhanced and the grain size is increased, whereas a higher annealing temperature will lead to the deterioration of the orientation and microstructures. The annealing temperature dependent dielectric, leakage and ferroelectric properties are investigated, showing excellent properties for the low temperature annealed BFO thin films. The mechanisms about annealing temperature effects are discussed. The results will provide an effective route to realize the integration of large-area BFO thin films on Si wafers by an all-solution approach with low cost.

Ilmenite-type compound ZnMnO3 was synthesized by high temperature and high pressure method. The phase is different from that synthesized at atmospheric pressure, it shows a hexagonal structure with a space group of R-3H (No. 148). Its lattice parameters are a = b = 4.9608 (2) A, c = 13.7876 (3) A at room temperature. The octahedrons of ZnO6 and MnO6 are stacked layer by layer. The electronic configuration is Zn2+Mn4+O3, where the antiferromagnetic (AFM) interaction between Mn4+ ions induces an AFM transition at 16.2 K. The results of the first principles calculation also indicates ZnMnO3 is a Mn4+ ions dominated AFM insulator with an energy gap of 1.34 eV.

Solution derived high-quality epitaxial BiFeO3 (BFO) thin films, with robust spontaneous polarization, are still desired because of their advantages. Herein, epitaxial BFO thin films and SrRuO3 bottom electrodes are prepared on LaAlO3 substrates via chemical solution deposition (CSD) technique. The influences of precursor solution on the microstructure and electrical properties are investigated by using nitrate salt and acetate salt system. The XRD and P-E hysteresis loops results demonstrate that the BFO thin film prepared by acetate salt system as a relatively green CSD route shows good epitaxial characteristic and ferroelectric performances. In addition, the effect of the annealing atmosphere on the microstructure and electrical properties are studied for the acetate salt derived BFO thin films. The microstructure and defects chemistry are analyzed by SEM and XPS, the BFO thin film annealed in air shows better comprehensive ferroelectric performances with the lowest leakage current and enhanced ferroelectric polarization due to the improved microstructure and decreased defect concentrations. The results here thus provide an instructive approach to optimize the growth of solution-derived epitaxial BFO-based thin films.

The structural, magnetic, dielectric and magneto-dielectric properties of tungsten bronze Ba4-xCaxNd2Fe1.5Co0.5Nb8O30 (0 ≤ x ≤ 0.9) were investigated. All the samples can be indexed with the tetragonal structure and the space group of P4bm. The incorporation of Ca ions improves the structural distortion and promotes the grain’s growth. The magnetic curves at 300 K indicate the superposition of ferromagnetic (FM) and antiferomagnetic (AFM) state in all the samples, the observed FM phase can be attributed to the spin canting of AFM coupling of Fe- and Co-based sublattices. The Ca-doped samples exhibit an improved FM state due to large lattice distortion. The dielectric constant in anomaly region obeys well with Curie-Weiss law with γ = ∼1.6, implying that all the samples are relaxor ferroelectrics. The dielectric loss relaxations obey with Vogel-Fulcher relation and can be ascribed to the local polarization fluctuation induced by chemical heterogeneities. In addition, the relative change in magnetic field dependent dielectric constant follows with the change in the square of magnetization M2, suggesting that the observed magneto-dielectric is caused by the intrinsic magnetoelectric (ME) coupling effect. These results manifest that tungsten bronze compounds may be the potential candidates for the application in ME devices.

Integrating multiple functions in a single compound is still attractive and necessary to meet the demand of device miniaturization. In this work, we systemically modulate multifunctional properties in the 0.74BiFeO 3–0.26(Ba 0.85Ca 0.15)TiO 3– x wt. % MnO 2 solid solution with the addition of MnO 2. A highly rectangular and saturated polarization–hysteresis (P–E) loop is obtained with a large remanent polarization P r of 49.5 μC/cm 2 as x = 0.8. Furthermore, the piezoelectric coefficient d 33 also obviously improved with an optimized d 33 = 137 pC/N by the introduction of MnO 2 due to the grain size effect, the improvement of insulation, and relaxation regulation. With the addition of MnO 2, the remanent magnetization M r increases monotonically because of the enhanced exchange interactions between Fe 2 +and Fe 3 +. The results may provide an effective way to explore promising multifunctional materials in BiFeO 3-based ceramics.

Transparent conducting oxides (TCOs), combining the mutually exclusive functionalities of high electrical conductivity and high optical transparency, lie at the center of a wide range of technological applications. The current design strategy for n-type TCOs, making wide bandgap oxides conducting through degenerately doping, obtains successful achievements. However, the performances of p-type TCOs lag far behind the n-type counterparts, primarily owing to the localized nature of the O 2 p-derived valence band (VB). Modulation of the VB to reduce the localization is a key issue to explore p-type TCOs. This Perspective provides a brief overview of recent progress in the field of design strategy for p-type TCOs. First, the introduction to principle physics of TCOs is presented. Second, the design strategy for n-type TCOs is introduced. Then, the design strategy based on the concept of chemical modulation of the valence band for p-type TCOs is described. Finally, through the introduction of electron correlation in strongly correlated oxides for exploring p-type TCOs, the performance of p-type TCOs can be remarkably improved. The design strategy of electron correlation for p-type TCOs could be regarded as a promising material design approach toward the comparable performance of n-type TCOs.

Cr2Ge2Te6 is a rare layered ferromagnetic semiconductor that represents a promising material for novel thermoelectric and spintronic devices. High pressure is an effective way to change the electronic structure, and profoundly affects the physical and chemical properties of two-dimensional (2D) layered materials. Here we combined experimental results and theoretical calculations to investigate the structural evolution and properties of Cr2Ge2Te6under high pressure. It is found that Cr2Ge2Te6 undergoes an isostructural phase transition from layered to non-layered structure at ~14 GPa, accompanied with a semiconductor to metal transition, which is distinct from the previous reports. The pressure-induced metallization is verified by the overlap of the valence and conduction bands, and the layered-to-non-layered isostructural transition is attributed to the enhanced interlayer Te–Te interaction by First-principles calculations. Our results provide a potential pathway to control the structure and property of layered materials and possibility for conceptually new devices via pressure engineering.

Transition metal hydro/oxides (TMH/Os) are treated as the most promising alternative supercapacitor electrodes thanks to their high theoretical capacitance due to the various oxidation states and abundant cheap resources of TMH/Os. However, the poor conductivity and logy reaction kinetics of TMH/Os severely restrict their practical application. Herein, hierarchical core-shell P-Ni(OH)2 @Co(OH)2 micro/nanostructures are in situ grown on conductive Ni foam (P-Ni(OH)2 @Co(OH)2 /NF) through a facile stepwise hydrothermal process. The unique heterostructure composed of P-Ni(OH)2 rods and Co(OH)2 nanoflakes boost the charge transportation and provide abundant active sites when used as the intergrated cathode for supercapacitors. It delivers an ultrahigh areal specific capacitance of 4.4 C cm-2 at 1 mA cm-2 and the capacitance can maintain 91% after 10 000 cycles, showing an ultralong cycle life. Additionally, a hybrid supercapacitor composed with P-Ni(OH)2 @Co(OH)2 /NF cathode and Fe2 O3 /CC anode shows a wider voltage window of 1.6 V, a remarkable energy density of 0.21 mWh cm-2 at the power density of 0.8 mW cm-2 , and outstanding cycling stability with about 81% capacitance retention after 5000 cycles. This innovative study not only supplies a newfashioned electronic apparatus with high-energy density and cycling stability but offers a fresh reference and enlightenment for synthesizing advanced integrated electrodes for high-performance hybrid supercapacitors.

MoS2 has been regarded as one of the most promising anode materials for high-performance lithium-ion (LIBs) or sodium-ion batteries (SIBs) due to its unique two-dimensional (2D) layered structure. However, the unsatisfied structure stability and poor electrical conductivity limit the practical application of MoS2. Herein, a hierarchical yarn ball-like MoS2 nanosphere structure coated by N-doped carbon layer (MoS2-PVP@NC) is successfully developed to improve the structural stability and electrical conductivity of the MoS2 material. When evaluated as anode material for SIBs, the MoS2-PVP@NC electrode shows an excellent cycling performance of 410.2 mAh g−1 at 1 A g−1 after 200 cycles and an ultrahigh rate capability of 352.1 mAh g−1 at 10 A g−1. The composite electrode also presents a high cycling capacity of 607.1 mAh g−1 at 1 A g−1 after 300 cycles and high rate performance of 356.0 mAh g−1 at 10 A g−1 when used as anode for LIBs. The excellent electrochemical performance is attributed to the synergetic effect of the yarn ball-like nanosphere structure and the N-doped carbon layer. This work sheds light on the promising application of the hierarchical MoS2 composite in high-performance lithium-ion or sodium-ion storage system.

Epitaxial superconducting δ-MoN and δ-NbN thin films, exhibiting a superconducting transition temperature ( T c onset ) of 13 K and 10.3 K, respectively, were prepared by a simple chemical solution deposition on c-cut Al2O3 substrates. A sharp transition and the large residual resistivity ratio (RRR) ρ300K/ρonset of δ-MoN and δ-NbN thin films suggest high quality of the prepared epitaxial thin films. The critical current density (Jc) under 100 Oe at 5 K is of 1.37 and 0.74 MA/cm2 for the δ-MoN and δ-NbN thin films, respectively. The results will provide a facile route to prepare epitaxial superconducting metal nitride thin films.

Hard/soft interface plays a role in the properties of the composite metal-based magnets, while it is less talked in the composite permanent oxide magnets on the magnetic interaction and properties due to easy interdiffusion. Here, multilayer thin films composed with hard CoFe2O4 phase and soft La0.7Sr0.3MnO3 layers were choose and synthesized without interdiffusion by a chemical solution method. Furthermore, the effects of the annealing temperature and the number of soft layer on the magnetic interaction and properties are investigated. All composite films behavior as one rigidly coupled composite magnet at room temperature, and the magnetic properties increase with increasing annealing temperature. The coercivity and maximum magnetic energy product can respectively reach 8.27 kOe and 2.4 MG Oe at the temperature of 300 K. Exchange coupling was effectively enhanced and even dominate the magnetic interaction with less soft layers for the in-plane direction. Conversely, dipolar interaction predominates, but becomes weak in the composite films with more soft layers and attenuates with increasing annealing temperature for the out-of-plane direction. All of the results suggest that a suitable grain size of the hard phase and an improved interface may be more important for a rigidly coupled composite oxide magnet with good performance.

Stable material properties against large and frequent temperature variations are strongly desired in modern industry. Here we report the combination of low thermal expansion, high thermal conductivity and good mechanical properties in Hf0.87Ta0.13Fe2Cux, all of which are well retained from ambient down to cryogenic temperatures. Cu partially substitutes for Hf/Ta atoms, causing a continuous suppression of negative thermal expansion. For x ≥ 1.25 the precipitation of Cu phase remarkably improves the overall thermal conductivity and compressive strength of the compounds. The excellent comprehensive performance covering such a broad temperature window suggests the wide applications of current composites, for example in cryogenic engineering.

2D/2D heterostructures can combine the collective advantages of each 2D material and even show improved properties from synergistic effects. 2D Transition metal carbide Ti3C2 MXene and 2D 1T-MoS2 have emerged as attractive prototypes in electrochemistry due to their rich properties. Construction of these two 2D materials, as well as investigation about synergistic effects, is absent due to the instability of 1T-MoS2. Here, 3D interconnected networks of 1T-MoS2/Ti3C2 MXene heterostructure are constructed by magneto-hydrothermal synthesis, and the electrochemical storage mechanisms are investigated. Improved extra capacitance is observed due to enlarged ion storage space from a synergistically interplayed effect in 3D interconnected networks. Outstanding rate performance is realized because of ultrafast electron transport originating from Ti3C2 MXene. This work provides an archetype to realize excellent electrochemical properties in 2D/2D heterostructures.

Vertically aligned nanostructured (VAN) epitaxial La0.5Ca0.5MnO3 (LCMO) single-phase thin films have been achieved on (LaAlO3)0.3(Sr2AlTaO6)0.7 (001) [LSAT (001)] substrates under high magnetic fields applied in pulsed laser deposition processing. Low-field magnetoresistance (LFMR) in the LCMO VAN films can be effectively manipulated through varying the high magnetic field strength. The tunability of VAN on the electrical transport properties is dependent on control of the high magnetic field on the microstructures, including the geometrical arrangement, vertical interfaces, and vertical grain boundaries (GBs). An LFMR value as high as 45% at 150 K and 1 T has been achieved in an LCMO VAN film grown at 10 T, and its LFMR values are larger than 25% at 127–200 K and 1 T. The tunable and enhanced LFMR in the LCMO VAN films over a wide temperature range can be attributed to the increase in vertical interfaces and GB density with the increasing high magnetic field, which are highly related to the spin-polarized tunneling effect. Applying a high magnetic field in film deposition to control the microstructures of VAN single-phase films is a feasible route to achieve tunable and desirable physical properties.

Cu3NPdx thin films have been successfully prepared on glass substrates by a facile chemical solution deposition. Phase composition and surface morphology are evaluated by X-ray diffraction and field-emission scanning electronic microscope. The X-ray diffraction and X-ray photoelectron spectroscopy results reveal that palladium will occupy the body centre position. Pd dependent electrical and optical properties of the Cu3NPdx thin films are investigated. Electrical conductivity can be greatly improved and the indirect bandgap is decreased with increasing the palladium doping, and the optical band gap can be adjusted within the range of 1.40–1.04 eV. The results will provide a facile solution route to synthesize high-quality copper nitride thin films with low-cost and controllable optoelectronic performance.

1T phase MoS

Ferroelectric Bi6Fe2Ti3O18 (BFTO) thin films were deposited on flexible metallic Ni (200) tapes by chemical solution deposition method. The effects of annealing temperature and La0.5Sr0.5TiO3 (LSTO) buffer layer on the microstructure, dielectric, leakage and ferroelectric properties have been studied. With increasing annealing temperature, the crystallite size increases while the dielectric constant, the leakage current density, the coercive field and the remnant polarization increase initially and then decrease. At low annealing temperature BFTO thin films on Ni tapes display flat surface without cracks, no NiO phase and good ferroelectric hysteresis loops. At high annealing temperature improved ferroelectric properties can be only observed in BFTO thin films on Ni tapes with a LSTO buffer layers. It will provide an instructive route to prepare and optimize the properties of BFTO thin films on metallic tapes by chemical solution deposition method.

The magnetic and magnetocaloric effect (MCE) of Mg or Cu-doped Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 hexaferrites synthesized by the sol-gel method are investigated. The Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 shows a sharp paramagnetic to ferrimagnetic phase transition and a large conventional MCE at around room temperature. By the partial substitution of Zn with Mg or Cu, the magnetic transition temperature as well as the maximum MCE temperature can be tuned in the range of 300 and 375 K while keeping the maximum MCE nearly unchanged, which are beneficial characteristics for their application as near room-temperature magnetic refrigerants. For Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 , it is found that the maximum values of magnetic entropy change –Δ S M and relative cooling power (RCP) are 1.27 J/kg K and 124 J/kg for Δ H =4.4 T, respectively. Given its advantages, such as large RCP, suitable working temperature, low-cost raw materials, easy to synthesize, and environment-friendly, the Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 related hexaferrites may be potential candidates for room-temperature magnetic refrigeration.

As the most-studied multiferroic material, (111)-oriented BiFeO3 (BFO) thin films are desirable due to the highest polarization in the (111) plane. The difficulty of achieving large-area (111)-oriented BFO films on silicon wafers towards implementation with silicon technology has hindered the development of BFO films. Herein, we report the annealing temperature effects on chemical solution deposition (CSD) derived BFO films on Pt(111)/Ti/SiO2/Si substrates without any buffer layer. The derived BFO films shows a strong (111) orientation with a distorted rhombohedral structure and R3c space group. The annealing temperature effects on the microstructures as well as the properties were investigated. A dense and crack-free surface was obtained in the low-temperature annealed films. Relatively high room-temperature remnant polarization 2Pr (120–140 μC cm−2) could be obtained with low leakage (∼10−5 A cm−2 at 200 kV cm−1). Scanning electron microscopy and transmission electron microscopy showed that this is an available route for fabricating large-area (111)-oriented BFO films on silicon-based wafers with high 2Pr using low-cost solution processing.

Many studies have shown that the pathogenesis of liver injury includes oxidative stress. MicroRNA-122 may be a marker for the early diagnosis of drug-induced liver injury. However, the relationship between microRNA-122 and oxidative stress in anti-tuberculosis drug-induced liver injury remains unknown. We measured changes in tissue microRNA-122 levels and indices of oxidative stress during liver injury in mice after administration of isoniazid, a first-line anti-tuberculosis drug. We quantified microRNA-122 expression and indices of oxidative stress at 7 time points, including 1, 3, and 5 days and 1, 2, 3, and 4 weeks. The tissue microRNA-122 levels and oxidative stress significantly changed at 3 and 5 days, suggesting that isoniazid-induced liver injury reduces oxidative stress and microRNA-122 expression compared to in the control group (P < 0.05). Notably, over the time course of isoniazid-induced liver injury, mitochondrial ribosome protein S11 gene, the target of microRNA-122, began to change at 5 days (P < 0.05). The tissue microRNA-122 profile may affect oxidative stress by regulating mitochondrial ribosome protein S11 gene during isoniazid-induced liver injury, which may contribute to the response mechanisms of microRNA-122 and oxidative stress.

In this paper, Bi2Sr2Co2Oy and Bi2Ba2Co2Oy thin films were prepared on Ca3Co4O9/polycrystalline Al2O3 thin films by chemical solution deposition. The results show that both of the bismuth-based cobaltate thin films are self-assembled c-axis oriented, which confirms that Ca3Co4O9/polycrystalline Al2O3 thin film can be used as an effective template to induce c-axis oriented grain growth in layered cobaltate thin films. The annealing temperature effects on Bi2Sr2Co2Oy thin films were investigated, and the resistivity and Seebeck coefficient decrease with the increasing annealing temperature. The results will provide an effective template to realize self-assembled c-axis oriented layered cobaltate thin films on polycrystalline substrates by chemical solution deposition.

Preparation of antiperovskite thin films is challenging work due to their complex phase diagram and easy decomposition during processing, which hinder the fundamental studies and applications. Herein, we report the preparation of antiperovskite CuNCo3 (CNC) thin films on several different single crystal substrates by chemical solution deposition. The results show that the derived CNC thin films are c-axis oriented regardless of the substrate orientation, suggesting the self-assembled c-axis orientation. The microstructures as well as the physical properties are investigated, showing that the CNC thin films are metallic and can be considered as a new type of soft-magnet with a ferromagnetic Curie temperature higher than 650 K. The results will provide an effective route for fabricating antiperovskite cobalt-based thin films as well as provide a prototype for the investigation of the growth mechanisms of complex metal nitride thin films by solution methods.

M-type hexaferrites BaFe 12−2 x (NiTi) x O 19 ( x =0, 0.05, 0.1, 0.3, 0.5, 0.7, and 0.9) were synthesized by the solvothermal method. X-ray diffraction (XRD) analysis reveals that the samples are of pure-phase with the space group of p 6 3 / mmc . As the Ni–Ti substitution level increases from x =0 to 0.9, the results of field-emission scanning electronic microscopy indicate that the particles are agglomerated and the mean particle size decreases. With the increase in substitution concentration x , the saturation magnetization increases first, and then declines slowly, whereas the coercivity decreases gradually. The variation of magnetic properties can be explained by the effects of Ni–Ti substitution. The results above indicate that our samples have positive effects on high density perpendicular recording.

Monodisperse porous Ni 0.5 Zn 0.5 Fe 2 O 4 nanospheres have been successfully synthesized by the solvothermal method. The diameter of the nanospheres can be tuned by controlling the reactant concentration. Lower reactant concentration is favoured for the synthesis of mesoporous Ni 0.5 Zn 0.5 Fe 2 O 4 nanospheres with higher surface area. The electrochemical results show that mesoporous Ni 0.5 Zn 0.5 Fe 2 O 4 nanospheres exhibit high reversible specific capacity (1110 mAh g −1 ) for Li storage and high capacity retention, with 700 mAh g −1 retained up to 50 cycles. The excellent electrochemical properties could be attributed to the large surface area and mesoporous structure. The results suggest that Ni 0.5 Zn 0.5 Fe 2 O 4 could be a promising high capacity anode material for lithium ion batteries.

A large-scale cyclonic-static microbubble flotation column (FCSMC) was tested at the Xuehu coal preparation plant for processing of fine particles (−0.5 mm). A measure of the axial gas holdup profile provided reasons for the deteriorating performance of the FCSMC. The results showed that an excessive mass flow rate of the solids resulted in the loss of mineralized bubbles to the tailings stream, which was responsible for the drop in the combustible recovery and tailings ash. This phenomenon gives rise to the gas holdup profile inversion where the increase of gas holdup from bottom to top decreases. It was shown that the critical tailings velocity of gas holdup profile inversion is exactly the same with the inflection point of carrying capacity and combustible recovery, which demonstrates that it is feasible to diagnose the column operation through the measurement of the axial gas holdup profile.

Highly c-axis oriented Bi2–xNaxSr2Co2Oy (x = 0, 0.1, 0.2, 0.3) thin films were successfully deposited onto LaAlO3 (0 0 1) single crystal substrates by the chemical solution deposition method. The Na-doping effects on microstructures as well as transport and thermoelectric properties were investigated. The crystallite size normal to the thin film surface was decreased with Na doping, and the carrier concentration and mobility was enhanced and decreased, respectively. As for the transport properties, it is suggested that Na-doping-induced disorders play a more important role at low temperatures, while at the medium temperature the doping play a trivial role, at higher temperatures Na-doping weakens the electron correlation. Combined with the transport properties and Seebeck coefficient results, it is suggested that the thermoelectric properties are mainly controlled by carrier concentration due to the hole doping in blocking layers. Power factor at 300 K was enhanced about 22% for the Bi1.7Na0.3Sr2Co2Oy thin film as compared with that of the undoped thin films, suggesting that Na doping at blocking layer in Bi2Sr2Co2Oy was an effective route to enhance the thermoelectric power factor.

In this work, BiFeO3 (BFO) thin films were prepared on metallic Ni (200) tapes with and without a La0.5Sr0.5TiO3 (LSTO) buffer layer at different temperatures by chemical solution deposition. The effects of the annealing temperature as well as the LSTO buffer layer on the dielectric, leakage and ferroelectric properties have been studied in detail. The crystallite size, dielectric constant and leakage current density increase, while the coercive field decreases with increasing annealing temperature. The BFO thin films deposited directly on the Ni tapes are prone to wrinkling, while the wrinkles are smoothed by introducing a thin LSTO buffer layer. Decreased compressive microstrain as well as improved ferroelectric and leakage properties are observed in the BFO thin films deposited on the LSTO buffered Ni tapes. The results will provide an instructive route to optimize BiFeO3-based thin films on metallic tapes by chemical solution deposition methods.

CrN thin films are first prepared by a facile chemical solution deposition method. The results show that the derived CrN thin films are nanocrystalline with the grain size of 30–60 nm. X-ray photoelectron spectroscopy measurement shows the stoichiometry of the derived thin film. The temperature dependent resistivity within the range of 2–300 K shows a semiconductor-like behavior with dρ/dT < 0 and a discontinuity in resistivity at 253 K is observed due to the antiferromagnetic transition. At 10 K the magnetoresistance is as low as −0.06% under 45 kOe. The first growth of CrN thin films by the facile chemical solution deposition will provide an alternative route to prepare CrN thin films, especially for large-area CrN thin films with low-cost.

Flexible Ba2Bi4Ti5O18 and BiFe0.93Mn0.07O3/Ba2Bi4Ti5O18 heterostructure thin-film capacitors were deposited onto LaNiO3 buffered fluorophlogopite mica substrates using a cost-effective all-solution chemical solution deposition method. The Ba2Bi4Ti5O18 film showed a high recoverable energy storage density (Ure) of 41.2 J/cm3 and efficiency (η) of 79.1%. The BiFe0.93Mn0.07O3/Ba2Bi4Ti5O18 film showed improved energy storage properties with an ultrahigh Ure of 52.6 J/cm3 and η of 75.9% due to its enhanced breakdown field strength and polarization. Meanwhile, both films showed good mechanical flexibility, excellent fatigue endurance up to 5 × 108 cycles, and excellent thermal stability over a wide temperature range from room temperature to 160 °C. These results indicate that the lead-free, flexible Ba2Bi4Ti5O18 and BiFe0.93Mn0.07O3/Ba2Bi4Ti5O18 heterostructure thin film capacitors show promise in the field of flexible electronics.

Bismuth ferrite (BiFeO3 ) has recently become interesting as a room-temperature multiferroic material, and a variety of prototype devices have been designed based on its thin films. A low-cost and simple processing technique for large-area and high-quality BiFeO3 thin films that is compatible with current semiconductor technologies is therefore urgently needed. Development of BiFeO3 thin films is summarized with a specific focus on the chemical solution route. By a systematic analysis of the recent progress in chemical-route-derived BiFeO3 thin films, the challenges of these films are highlighted. An all-solution chemical-solution deposition (AS-CSD) for BiFeO3 thin films with different orientation epitaxial on various oxide bottom electrodes is introduced and a comprehensive study of the growth, structure, and ferroelectric properties of these films is provided. A facile low-cost route to prepare large-area high-quality epitaxial BFO thin films with a comprehensive understanding of the film thickness, stoichiometry, crystal orientation, ferroelectric properties, and bottom electrode effects on evolutions of microstructures is provided. This work paves the way for the fabrication of devices based on BiFeO3 thin films.

Epitaxial BaSnO3 (BSO) thin films doped with different rare-earth elements (La, Pr, and Nd) were prepared by a simple solution deposition method. Grain size engineering through processing was achieved to tune both lateral and vertical grain sizes, resulting in obvious increments in carrier mobility. Improved performance with the room-temperature mobility exceeding 35 cm2 V−1 s−1 and resistivity as low as 0.55 mΩ cm was realized. The results will open a low-cost route for preparation of large-area BSO thin films with improved optoelectronic properties through the solution method.

1T phase MoS2 possesses higher conductivity than the 2H phase, which is a key parameter of electrochemical performance for lithium ion batteries (LIBs). Herein, a 1T-MoS2 /C hybrid is successfully synthesized through facile hydrothermal method with a proper glucose additive. The synthesized hybrid material is composed of smaller and fewer-layer 1T-MoS2 nanosheets covered by thin carbon layers with an enlarged interlayer spacing of 0.94 nm. When it is used as an anode material for LIBs, the enlarged interlayer spacing facilitates rapid intercalating and deintercalating of lithium ions and accommodates volume change during cycling. The high intrinsic conductivity of 1T-MoS2 also contributes to a faster transfer of lithium ions and electrons. Moreover, much smaller and fewer-layer nanosheets can shorten the diffusion path of lithium ions and accelerate reaction kinetics, leading to an improved electrochemical performance. It delivers a high initial capacity of 920.6 mAh g-1 at 1 A g-1 and the capacity can maintain 870 mAh g-1 even after 300 cycles, showing a superior cycling stability. The electrode presents a high rate performance as well with a reversible capacity of 600 mAh g-1 at 10 A g-1 . These results show that the 1T-MoS2 /C hybrid shows potential for use in high-performance lithium-ion batteries.