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Cobalt ferrite (CFO), barium titanate (BTO) core-shell nanoparticles (CFO:BTO NPs) exhibit multiferroic properties through the magnetoelectric effect. Inkjet printing is a direct-write, additive manufacturing technique for fabrication of electronic components and devices. Hansen Solubility Parameters (HSP) are a practical tool to understand solution and dispersion behavior of materials in a mixture. This work applies HSP analysis to improve CFO:BTO NPs synthesis and guide the ink formulation process. The estimated HSP values for CFO:BTO core-shell NPs (dD = 15.5, dP = 11.9, dH = 23, r = 4.6), CFO (dD = 15.9, dP = 10.6, dH = 22.5, r = 4.9), and BTO (dD = 16.6, dP = 9.7, dH = 15.4, r = 5.8) are analyzed. Limits and considerations of the HSP are discussed and results are combined with solvent thermal and fluid properties to develop ink formulations for multi-functional, multi-material inkjet printing applications. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF) hafnium-based UiO-66 is a promising material for piezoelectric pressure sensors. The synthetic material is advantageous due to its tunability, porosity, and capability for wearable technology. Additionally, MOF UiO-66 possesses superior stability and exhibits both piezoelectric and ferroelectric responses. The material is synthesized via a solvothermal approach and examined through XRD, FT-IR, and UV-Vis spectroscopy. This study aims to evaluate the piezoelectric and ferroelectric properties and investigate the preliminary steps of incorporating a UiO-66 formulated functional ink with interdigitated electrodes by drop casting a thin film onto printed silver interdigitated electrodes and observing compatible solvents for ink formulation. [ABSTRACT FROM AUTHOR]

In this study, nanocomposite poly(lactic acid) and poly(butylene adipate‐co‐terephthalate) (PLA/PBAT) blends were prepared through polymer blending in the presence of multi‐functional epoxy as a compatibilizer that could react with epoxy group and terminated end group of two phases to increase interfacial adhesion between PLA and PBAT and improve the toughness of PLA. The effects of porous clay heterostructure from mixed CTAB:CTAC surfactant in the mole ratio of 1:2 (B1C2‐PCH) were also investigated. The elongation at break of the blends reached 38%, which was eight times that of neat PLA. The cryo‐fractured surface demonstrated the interfacial adhesion caused by the interaction of the epoxy group of the reactive compatibilizer with the terminal carboxyl and hydroxyl groups of PLA and PBAT. Moreover, PBAT reduced the crystallization rate and percent crystallinity of the PLA matrix and further decreased when compatibilizer was used. Alternatively, B1C2‐PCH accelerated the heterogeneous nucleation and crystallization of the nanocomposite films. After adding small amount of B1C2‐PCH, the nanocomposite films demonstrated excellent dielectric properties. Therefore, the improvement of PLA/PBAT nanocomposite blends are capable to be further developed as polymeric capacitor films. [ABSTRACT FROM AUTHOR]

The present paper reports the multifunctional properties of lead‐free BiFeO3–La (BFO–La) thin films. The structural, microstructural, and optical properties have been investigated as a function of the lanthanum doping concentration. The structural properties at room temperature showed the formation of the perovskite structure, thus suggesting the high quality of the obtained thin film compositions. Raman spectroscopy analysis revealed a slight variation in both the peak position and absolute intensity for the Raman active modes, as lanthanum content increases in BiFeO3–La. Crystallized thin films with well‐defined grains as well as crack‐free surfaces have been obtained, for all the studied compositions, as inferred from atomic force microscopy images. The optical properties have been measured, and the values for the direct bandgap was significantly lower than those reported for other BFO‐based systems, being the lowest ∼1.87 eV for the Bi0.90La0.10FeO3 composition. Results revealed a noteworthy effect of the defect concentrations induced by the lanthanum doping on the long‐range crystallinity and directly affecting the polarizability of the A–O bond as well as the Fe–O and Fe–O–Fe bond lengths in the perovskite structure. The enhanced optical absorption properties registered for the Bi1–xLaxFeO3 (x = 0–20) compositions make these perovskite multiferroic thin films as a potential candidate material for the high‐performance photovoltaic device applications. [ABSTRACT FROM AUTHOR]

The effects of processing techniques significantly alter on the electroactive β‐phase, thermal, and dielectric behavior of polymer composites. The metal–organic framework filler (C3N2H5)(Mg(HCOO)3), HImMg is prepared and introduced into poly(vinylidenefluoride‐co‐hexafluoropropylene) (PVDF‐HFP) matrix using two distinguished methods: melt‐mixing and solution‐casting methods. The processing conditions are important in determining the dominant phase in PVDF‐HFP. As a result of solvent‐induced crystallization, the β‐phase content of solution‐cast composites containing 10% HImMg is 22% higher than that of melt‐mixed composites. In both methods, the nucleating effect of HImMg particles increases the overall crystallinity of the polymer matrix and enhances the dielectric constant in composite films by improving the interfacial and dipolar polarization. Furthermore, the melt‐mixed composites with 7 wt% HImMg demonstrate the highest dielectric constant of 17.8 at 1 kHz, showing an enhancement of 59% compared with that of pristine PVDF‐HFP. Meanwhile, the dielectric loss is suppressed at 0.083. These findings suggest the possibility of enhancing composites' electroactive phase and dielectric properties without mechanical stretching or a large electrical field. [ABSTRACT FROM AUTHOR]

The dielectric response near the permittivity maximum achieved at the paraelectric-ferroelectric phase transition in (Sr(sub 0.8)Pb(sub 0.2))TiO(sub 3) ceramic ferroelectric solid solutions is investigated. The results show that the highest permittivity peak samples are less homogenous, indicating that micropolarity might be associated with inhomogeneity in the lead cation distribution.