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The magnetization mechanism of Co-doped BaTiO3 ultrathin films is a subject of debate, which results in difficulties with the design of new multiferroics based on BaTiO3 matrixes. With the aid of a first-principles approach, it was observed that when the interstitial site and Ti vacancy were filled with Co, the configuration behaved in a nonmagnetic manner, indicating the significance of the Co content. Moreover, in the case of Co substituting two neighboring Ti atoms, when a direct current field was applied in the [100] direction, the magnetic domains excluding those in the [100], [010], and [001] directions were directed away. Further, the magnetoelectric constant was evaluated at ~449.3 mV/cmOe, showing strong magnetoelectric coupling at room temperature. Clearly, our study indicates that strict control of Ba, Ti, O, and Co stoichiometry can induce an electric and magnetic field conversion in two-dimensional BaTiO3 and may provide a new candidate for single-phase multiferroics for application in next-generation multifunctional devices.

Chloride-ion batteries (CIBs) are one of the promising candidates for energy storage due to their low cost, high theoretical energy density and high safety. However, the limited types of cathode materials in CIBs have hindered their development. In this work, a NiTi-LDH@CNT composite is prepared using a reverse microemulsion method and applied in CIBs for the first time. The specific surface area and the pore volume of the obtained NiTi-LDH@CNT composites can reach 266 m2 g−1 and 0.42 cm3 g−1, respectively. Electrochemical tests indicate that the composite electrode delivers a reversible specific capacity of 69 mAh g−1 after 150 cycles at a current density of 100 mA g−1 in 0.5 M PP14Cl/PC electrolyte. Ni2+/Ni3+ and Ti3+/Ti4+ valence changes during electrochemical cycling are demonstrated by X-ray photoelectron spectroscopy (XPS), while reversible migration of Cl− is revealed by ex-situ EDS and ex-situ XRD. The stable layered structure and abundant valence changes of the NiTi-LDH@CNT composite make it an exceptional candidate as a cathode material for CIBs.

This paper presents the concrete design of nanowires under the precise size and morphology that play a crucial role in the practical operation of the micro/nano devices. A straightforward and operative method termed as nib-assistance coaxial electrohydrodynamic (CEHD) printing technology was proposed. It extracts the essence of a nib-assistance electric field intensity to enhance and lessen the internal fluid reflux of the CEHD jet. The experiments were performed to add microparticles into the inner liquid to indicate the liquid flow consistency within the coaxial jet. The reflux in the coaxial jet was observed for the first time in experiments. The nanowires with a minimum size of 70 nm were printed under optimum experimental conditions. The nanopatterns contained aligned nanowires structures with diameters much smaller than the inner diameter of nozzle, relying on the coaxial nib-assisted technique. The printed results revealed that the nib-assisted CEHD printing technique offers a certain level high quality for application of NEMS system.

Co3O4 nanorods were prepared by a facile hydrothermal method. Eco-friendly deionized water rather than organic solvent was used as the hydrothermal media. The as-prepared Co3O4 nanorods are composed of many nanoparticles of 30–50 nm in diameter, forming a finger-like morphology. The Co3O4 electrode shows a specific capacitance of 265 F g−1 at 2 mV s−1 in a supercapacitor and delivers an initial specific discharge capacity as high as 1171 mAh g−1 at a current density of 50 mA g−1 in a lithium ion battery. Excellent cycling stability and electrochemical reversibility of the Co3O4 electrode were also obtained.