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PbZrO3 (PZO)‐based antiferroelectric thin films are of great interest due to their high‐power density and fast charging and discharging capability. However, the problems of low breakdown strength and inferior energy storage density of PZO films have not been well solved. In this work, the insulating MgO as the blocking interlayer is inserted into PbZrO3 films (abbreviated as P/M/P), which can inhibit the electric charge transfer and enhance the breakdown strength, as well as regulation of the polarization behavior. The results show that the maximal endurable electric field is significantly improved, and the double‐hysteresis characteristic disappeared after introducing MgO blocking interlayer. The energy storage density of P/M/P films reaches 21.97 J/cm3 under 1700 kV/cm, accompanying an ultralow efficiency of 44.01% due to the severe polarization loss. Furthermore, low‐temperature annealing is performed to suppress the polarization loss, and an energy storage density of 17.27 J/cm3 accompanying a high efficiency of 75.53% is obtained at 3100 kV/cm, still exhibiting good stability after 1 × 107 fatigue cycles. This study demonstrates that combining the insulating interlayer and the low‐temperature annealing endow the PZO‐based films significantly improved energy storage properties, having great potential to be used in the dielectric capacitors. [ABSTRACT FROM AUTHOR]

In this paper, Bi2212 films were prepared on LaAlO 3 (100) and SrTiO 3 (100) substrates by the sol-gel method using Bi(NO 3) 3 ·5H 2 O, Sr(NO 3) 2 , Ca(NO 3) 2 ·4H 2 O and Cu(NO 3) 2 ·3H 2 O as raw materials. TritonX-100 (TX-100), fatty alcohol poly oxyethylene ether (AEO-9), poly (vinylpyrrolidone) (PVP) and poly (vinyl alcohol) (PVA) were used as surfactants, respectively, to improve the wettability between the sol and the substrate. When glycine and glycolic acid were used as complexing agents, these surfactants were stably miscible with the sols. The effects of different surfactant sol-gel systems on the wettability of substrates as well as the crystallinity, morphology, surface roughness and electrical transport properties of Bi2212 superconducting films were investigated. The results showed that flat and continuous c -axis epitaxial Bi2212 films were obtained using all these sol-gel systems. In particular, TX-100 and AEO-9 as surfactants showed stronger wettability of the sol-gel for both substrates. In addition, the films prepared using polymer surfactants PVP and PVA sol-gel systems showed less surface roughness. The same patterns were found in all the film samples prepared using precursor sols of different complexing agents, and all the films exhibited good electrical transport properties. This work lays a certain research foundation for the preparation of thin films by aqueous solvent sol-gel method. The method also shows great potential in terms of the stability of different sol-gel systems and the improvement of the wettability of different substrates. [ABSTRACT FROM AUTHOR]

The complexed sol-gel method has unique advantages in the preparation of multi-component functional thin films. In this paper, Bi2212 superconducting thin films were prepared by sol-gel method on SrTiO 3 (100) single crystal substrates. Glycine and glycolic acid were used as complexing agents. The thermal decomposition processes of the two sols were analyzed by contrasting thermal-thermogravimetric curves. The heat treatment processes of the different complexing agent systems were optimized to obtain films with flatter surface morphology. The phase composition of the intermediate products during the precursor heat treatment was changed by adjusting the conditions of the complexing agent and the acidity of the sol, which expanded the pure phase temperature interval of the final product. The pure phase temperature interval, morphology, surface roughness, and electrical transport properties of Bi2212 superconducting films prepared with different complexing agent sol-gel systems were investigated. When glycolic acid was used as the complexing agent, the Bi-2212 superconducting films showed the widest phase formation temperature zones of 25 K. They also had a smaller surface roughness of 10–15 nm. Other than that, all samples had good epitaxial properties, and electrical transport properties. This work provides a new idea for expanding the phase-forming temperature region of multicomponent functional ceramics. It also shows the promising potential of sol-gel method for preparing multicomponent functional films with high quality surfaces. [ABSTRACT FROM AUTHOR]

In order to achieve flexible applications of superconducting thin film materials in devices, the surface quality of the film is critical. The thickness of the film is one of the important factors affecting its surface quality. In this paper, Bi2212 superconducting thin films of different thicknesses were prepared on LaAlO 3 (100) and SrTiO 3 (100) single crystal substrates by sol-gel method and the effects of film thickness and different heterogeneous structures on their crystallographic, morphological and superconducting properties were investigated. The results showed that the roughness gradually increased with increasing Bi2212 thickness at the initial stage of film growth and stabilized after reaching a certain thickness, while the superconducting properties were destroyed at very small sample thickness, which was consistent in both single-crystal substrate films. In the Bi2212/LaAlO 3 structure, the surface quality of the sample was excellent with a roughness of 5.4 nm at a thickness of about 18 nm for Bi2212, and the growth of the precipitated phase was inhibited to a greater extent. The film also had good superconductivity. This work provided a further research basis for the preparation of high quality Bi2212 films and offers further possibilities for their practical application. [Display omitted] • Preparation of epitaxially grown multi-component functional thin films-Bi2212 superconducting films. • Effective regulation of film thickness. • Effective improvement of the surface quality of the film by regulating the thickness of the film. • Modelling the variation process of the effect of film thickness on its surface quality. [ABSTRACT FROM AUTHOR]

Antiferroelectric film capacitors have attracted increasing attention due to their excellent energy storage properties. In this work, PbZrO 3 (PZO) antiferroelectric films have been prepared on the flexible fluorphlogopite (Mica) and rigid Pt/Ti/SiO 2 /Si substrates with a seed layer of LaNiO 3 (LNO) layer by sol-gel process. The microstructure and energy storage properties of the films have been systematically studied. The results show that the Mica-Pt-LNO-PZO (M -LNO-PZO) thin film has an improved energy storage density (W rec) of 16.6 J/cm3 with a charge and discharge efficiency (η) of 50.4%. Furthermore, the flexible thin films exhibit good stability under a wide working temperature range of 25–140 °C and an electric fatigue endurance of 107 cycles. Besides, the capacitive films can endure a bending radius of 4 mm and 104 bending cycles (@ r = 4 mm) with almost unchanged in the energy storage properties. The excellent energy storage properties endow inorganic thin films with great potential in flexible electronic devices. [ABSTRACT FROM AUTHOR]

• The Li+ doping can improve the ferroelectricity of lead zirconate films. • Adjusting the annealing temperature can increase the breakdown field strength. • A superior efficiency of 82.38 % is obtained in the Pb(Zr 0.92 Li 0.08)O 3. • A remarkable energy storage density of 29.53 J/cm3 is obtained in the Pb(Zr 0.92 Li 0.08)O 3. The lead zirconate (PZO) anti-ferroelectric thin film capacitors, known for their high power density and rapid discharge speed, have garnered significant attention for applications in energy storage. Efficient strategies to enhance energy storage performance include doping and low-temperature annealing. PZO-based films, grown on Pt/Ti/SiO 2 /Si using the sol-gel method, undergo modification through Li+ doping to enhance polarization and lowering the annealing temperature to improve the breakdown electric field. The results indicate that Pb(Zr 0.92 Li 0.08)O 3 films, annealed at 550°C, exhibit a high energy storage density of 29.53 J/cm3, an efficiency of 82.38 % in an electric field of 4000 kV/cm, and maintain excellent electrical properties through 107 charge-discharge cycles. This study demonstrates that doping and low-temperature annealing enhance the energy storage properties of Pb(Zr 0.92 Li 0.08)O 3 -based films, rendering them highly promising for application in dielectric capacitors. [ABSTRACT FROM AUTHOR]

The oriented growth and morphology of polycrystalline bismuth (Bi) films deposited on insulating substrates is investigated based on the molecular beam epitaxy method. The film thickness effect on the resistance-temperature characteristics and magnetoresistance properties is analyzed. The Bi film resistivity with thickness range [25, 65] nm is investigated using the four-probe method at 2–300 K. The magnetic field contributes to opening the energy gap of Bi thin films and a more obvious opening of the energy gap is observed in the thinner films. The Bi film has the weak antilocalization (WAL) effect and the thickness increase affects the WAL effect. The large magnetic field is beneficial to the observation of the WAL effect. The temperature-dependent resistivity of Bi thin films is described based on the Ziman-Faber theory. The competition between the metal surface state and the bulk state explains the semimetal-semiconductor transition and the magnetoresistance effect in the thickness range [25, 65] nm. In addition, the thickness effect on the magnetoresistance property is researched, which provides a new approach to specify the Bi thin film magnetoresistance. • Polycrystalline films with preferred orientation were prepared by MBE method. • Oriented growth improves the magnetoresistance properties of polycrystalline films. • Magnetic field contributes to the opening of semimetal energy gap. • Oriented growth is an effective strategy to improve the alloy polycrystalline film property. [ABSTRACT FROM AUTHOR]

BaSn 0.15 Ti 0.85 O 3 (BTS) thin films were deposited on Pt/Ti/SiO 2 /Si(1 0 0) substrate by pulsed laser deposition and the effects of substrate temperature on their structure, dielectric properties and leakage current density were investigated. The results indicate that the substrate temperature has a significant effect on the structural and dielectric properties of the BTS thin films which exhibit a polycrystalline perovskite structure if the substrate temperature ranges within 550–750 °C. The dielectric constant and loss tangent of the BTS thin films deposited at 650 °C are 341 and 0.009 at 1 MHz, respectively, the tunability is 72.1% at a dc bias field of 400 kV/cm, while the largest figure of merit (FOM) is 81.1. The effect of the substrate temperature on the leakage current of the BTS thin films is discussed. [ABSTRACT FROM AUTHOR]

The crystal growth and transport properties of the polycrystalline Bi(0001) films grown on MgO(001) and glass substrates were compared. The morphology and electron transport properties with different thickness have been analyzed. The stress-induced bandgap leads to the shift of transition temperature from semimetal to semiconductor transition. Compared with MgO(001) substrates, Bi(0001) thin films on glass substrates have the higher semimetal-semiconductor transition temperature. Furthermore, the electron transport performance is improved, which is attributed to the strain-free van-der-Waals epitaxial preferred orientation grown on the glass substrate. The strain effect on the transport performance is greater than that on in-plane grain boundaries. • Compare the crystal orientation of polycrystalline Bi film on MgO and glass substrate. • Bi films with preferred orientation have excellent electrical transport property. • Strain has a greater influence on the Bi film transport property than grain boundary. [ABSTRACT FROM AUTHOR]

During the preparation of Bi 2 Sr 2 CaCu 2 O 8+ δ (Bi2212) superconducting thin films by sol-gel method, the complexing agent and sintering conditions can significantly influence the quality and the performance of thin film. In this study, Bi2212 thin films were prepared on single crystal SrTiO 3 (001) substrate, and the phase purity, crystallinity, surface morphology and transport properties were studied particularly with different sintering temperature and time, complexing agent and its ratio to metal ions. Due to relatively low carbon content, tartaric acid (TA) as a complexing agent improved the film quality and transport properties compared with the traditional ethylenediamine tetraacetic acid (EDTA). When the complex ratios of TA to metal ions was 1:1, Bi2212 thin films exhibited good epitaxial properties, a high Bi2212 phase purity and a low surface roughness of 12.74 nm. Simultaneously, under these preparation condition, Bi2212 superconducting thin film showed a higher T c, onset of 93.28 K. [ABSTRACT FROM AUTHOR]

2D conductive metal–organic frameworks (2D c‐MOFs) feature promising applications as chemiresistive sensors, electrode materials, electrocatalysts, and electronic devices. However, exploration of the spin‐polarized transport in this emerging materials and development of the relevant spintronics have not yet been implemented. In this work, layer‐by‐layer assembly was applied to fabricate highly crystalline and oriented thin films of a 2D c‐MOF, Cu3(HHTP)2, (HHTP: 2,3,6,7,10,11‐hexahydroxytriphenylene), with tunable thicknesses on the La0.67Sr0.33MnO3 (LSMO) ferromagnetic electrode. The magnetoresistance (MR) of the LSMO/Cu3(HHTP)2/Co organic spin valves (OSVs) reaches up to 25 % at 10 K. The MR can be retained with good film thickness adaptability varied from 30 to 100 nm and also at high temperatures (up to 200 K). This work demonstrates the first potential applications of 2D c‐MOFs in spintronics. [ABSTRACT FROM AUTHOR]

Nanocomposite foam with a large expansion ratio and thin cell walls is promising for electromagnetic interference (EMI) shielding materials, due to the low electromagnetic (EM) reflection and high EM absorption. To overcome the dimensional limitation from two-dimension (2D) thin walls on the construction of conductive network, a strategy combining hybrid conductive nanofillers in semi-crystalline matrix together with supercritical CO2 (scCO2) foaming was applied: (1) one-dimension (1D) CNTs with moderate aspect ratio was used to minimize the dimensional confinement from 2D thin walls while constructing the main EM absorbing network; (2) zero-dimension (0D) carbon black (CB) with no dimensional confinement was used to connect the separated CNTs in thin walls and to expand the EM absorbing network; (3) scCO2 foaming was applied to obtain a cellular structure with multi-layer thin walls and a large amount of air cells to reduce the reflected EM; (4) semi-crystalline polymer was selected so that the rheological behavior could be adjusted by optimizing crystallization and filler content to regulate the cellular structure. Consequently, an advanced material featured as lightweight, high EM absorption and low EM reflection was obtained at 0.48 vol.% hybrid nanofillers and a density of 0.067 g/cm3, whose specific EMI shielding performance was 183 dB cm3/g. [ABSTRACT FROM AUTHOR]