Ferroelectric nematic liquid crystals (FNLCs) constitute a newly established and rapidly evolving class of soft materials in which long range orientational order coexists with the spontaneous macroscopic polarization (P). Unlike conventional apolar nematics (N), ferroelectric nematic (FN) phase breaks inversion symmetry, leading to exceptionally strong electro-optic (EO), dielectric, mechanical and nonlinear optical (NLO) responses at ultra-low driving fields. The present work surveys and contextualizes major experimental, theoretical and materials advances in FN, covering molecular design, phase behavior, interfacial alignment, elasticity, dielectric dynamics, NLO and emerging device concepts. Studies on highly polar rod like and bent core mesogens reveal spontaneous polarization values of 2–7 µC cm-2, dielectric permittivity approaching 104–105, NLO coefficients up to 25 pm V-1 and voltage controlled switching behavior. The studies also report that such behavior of FN arises from the interplay of strong dipole–dipole correlations, flexoelectric effects, coupling between polarization and director fields, elastic constant softening and electrostatic interactions at surfaces and interfaces. These properties enable transformative applications of FN in low power EO devices, photonics, actuators, adaptive optics, microfluidics and soft ferroelectric technologies. Despite the rapid progress, significant challenges remain including ionic effects, viscosity, surface anchoring control, defect management and stabilization of room temperature FN phases. Overall, FNLCs open a fundamentally new paradigm bridging soft condensed matter physics, molecular engineering and next generation functional devices.
We report the fabrication and systematic performance evaluation of ZnO thin film and ZnO/poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene](MDMO-PPV) heterojunction based piezoelectric nanogenerators (PENG) for vibration energy harvesting applications. The ZnO/MDMO-PPV heterojunction-based PENG with optimized MDMO-PPV thickness of 260 nm exhibited a maximum open circuit voltage and short circuit current of 2.35 V and 0.48 µA respectively with a power density of 0.1µW/cm2, representing an approximately 12-fold enhancement compared with ZnO thin film-based PENG. To understand the origin of this performance improvement, photoemission spectroscopy was employed to investigate the interfacial electronic structure of the ZnO/MDMO-PPV heterojunction and estimated the conduction band offset of 1.2 eV. This substantial band offset effectively suppresses leakage current by blocking interfacial carrier backflow, thereby reducing piezoelectric charge screening, enhancing charge separation, and consequently improving the output characteristics of the heterojunction-based PENG. The practical applicability of the ZnO/MDMO-PPV heterojunction-based PENG was demonstrated through biomechanical energy harvesting under continuous bending movements of finger, wrist and leg. The rectified output was successfully used to charge various commercial capacitors and the powering capability was further validated by flashing of a stop watch display and commercial LEDs, highlighting the potential of ZnO/MDMO-PPV heterojunction-based PENG for self-powered wearable and portable electronic applications.
A novel series of Sm3+ ions doped Boro-telluro-silicate glasses modified with various alkali and alkaline earth ions were synthesized following the technique of conventional melt-quenching. They were systematically examined to assess their potential for warm reddish-orange luminescence applications. The network structure of the glasses were analysed employing the Raman spectroscopy. The UV–Vis-NIR absorption spectra were carried out and it exhibits seven distinct absorption peaks with the hypersensitive 6H5/2 → 6F7/2 transition being the prominent. These spectra were used to uncover the nature of the glass material through the nephelauxetic ratios and bonding parameters. These results conclude that the Sm3+-ligand interactions were highly ionic. Especially, the BTSCa:Sm glass is highly ionic in nature. These were further confirmed through JO analysis and the obtained parameters follows the order as Ω4 > Ω6 > Ω2. Emission spectral studies reveal dominant reddish-orange luminescence arising from the hypersensitive 4G5/2 → 6H7/2 transition. The quantum efficiency falls in the range of 36
This study synthesized the lithium boro-vanadate glasses containing electric arc furnace slag (EAFS) using the melt-quenching technique. The effects of V2O5 and Slag on structural, thermal, and optical properties were systematically investigated. Thermal analysis identified the x = 7.5 wt
Developing scaffolds that simultaneously support tissue regeneration and prevent infection remains a major challenge in fabricating tissue engineering candidates. In this study, we successfully functionalized as-spun electrospun polyurethane (PU) nanofibrous scaffolds with calcium titanate (CaTiO3) and silver (Ag) nanoparticles (NPs) using a facile bath-sonication approach. Initially, CaTiO3 NPs were synthesized via a hydrothermal route, while Ag NPs were prepared through sodium borohydrate reduction. Morphological and structural analyses confirmed the formation of crystalline perovskite CaTiO3 and face-centered cubic Ag NPs. The SEM and XRD results indicated that the NPs were uniformly immobilized on as-spun nanofibers without compromising their fibrous integrity. The pristine PU scaffold exhibited a Young’s modulus of 0.7 ± 0.46 MPa and tensile strength of 1.9 ± 1.52 MPa, while the hybrid scaffolds with 3 wt
