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This work focuses on the development of a composite polymer electrolyte (CPE) for all‐solid‐state lithium metal batteries (ASSLMBs), integrating LLTO nanofibers into a PEO (polyethylene oxide)‐PVDF‐HFP (poly(vinylidene fluoride‐cohexafluoropropylene)) matrix with LiClO4 as the lithium salt. The PEO has high ionic conductivity and flexibility, and the PVDF‐HFP has high mechanical strength and electrochemical stability. Therefore, the resulting composite has improved electrochemical performance and mechanical properties. Incorporating LLTO nanofibers enhances ionic conductivity due to the one‐dimensional ion transport pathways provided by the nanofibers while maintaining mechanical integrity and air stability, overcoming the challenges associated with conventional fillers. The prepared CPE demonstrates exceptional electrochemical stability up to 5.1 V versus Li/Li+, making it suitable for high‐voltage applications over traditional polymer electrolytes. The optimized CPE with 15 wt% LLTO provides the ionic conductivity of 1.1 × 10−5 S cm−1 at room temperature and reaches 1.46 × 10−4 S cm−1 at 80°C. The assembled LiNi1/3Mn1/3Co1/3PO4||PEO‐PVDF‐HFP‐LiClO₄‐LLTO||Li based 2032 coin cell worked in between 3 and 4.8 V versus Li/Li+ potential window without any electrolyte decomposition from 0.5 to 5 mV/s scan rates. Similarly, the fabricated LiFePO₄||PEO‐PVDF‐HFP (1:2)‐LiClO4‐LLTO (15 wt%)||Li cell provides an initial capacity of 149 mAh g−1 at 0.1 C and 85 mAh g−1 at 0.5 C, exploring its potential for lithium metal batteries. Overall, this work offers a promising pathway for developing advanced solid polymer electrolytes for next‐generation lithium metal batteries, which combine high ionic conductivity, excellent electrochemical performances, and robust mechanical properties. [ABSTRACT FROM AUTHOR]

Herein, discrete γ‐KCoPO4 nanocrystals were prepared by a facile, green and fast sol‐gel route. The lattice parameters as well as positional and displacement parameters of atoms in the average γ‐KCoPO4 structure with a space group of P21/n were calculated using full profile Rietveld refinement. Monodispersed quadrangular γ‐KCoPO4 nanocrystals with improved phase purity and crystallinity were found through XRD patterns and HRTEM images. Subsequently, the prepared γ‐KCoPO4 nanocrystals were tested as electrode material for supercapatteries in aqueous electrolytes. The γ‐KCoPO4 electrode shows superior specific charge capacity of 309 C g−1 at 1 mV s−1 in 1 M KOH, compared to 1 M NaOH (222 C g−1) and 1 M LiOH (77 C g−1). Further, it exhibits improved electrochemical activity by delivering an impressive specific charge capacity of 100 C g−1 at a current of 0.6 mA cm−2 in an aqueous electrolyte medium with acceptable capacity retention. A lab‐scale supercapattery was assembled resembling the commercial device. The fabricated device delivered an enhanced specific energy of 28 W h kg−1 and a specific power of 1600 W kg−1 and prolonged cycle life of about 5000 cycles. The electrochemical performance of γ‐KCoPO4, one of the polymorphs of KCoPO4 is investigated intending the application in supercapatteries, the most promising contender of the energy storage systems. The electrochemical response of γ‐KCoPO4 polymorph is investigated with a variety of electrolytes, where the electrode unveils a higher specific charge capacity of ∼100 C g−1 in 1 M KOH electrolyte. [ABSTRACT FROM AUTHOR]

Combustion synthesized cobalt manganite (CMO) was systematically studied for its structural and magnetic properties. X-ray diffraction (XRD) pattern with high-intensity peaks at appropriate positions revealed the formation of phase pure and highly crystalline CMO. The distorted tetragonal structure of the CMO unit cell suggested the presence of high spin (d4) Jahn-Teller Mn3+ ions. X-ray photoelectron spectra (XPS) supported a mixed spinel with Co2+, Co3+, Mn2+ and Mn3+ cations. Electron microscopy confirmed the formation of submicron-sized CMO particles with well-defined lattice fringes, while low-temperature magnetic investigations revealed that the prepared CMO as a ferrimagnetic spinel due to the presence of uncompensated electronic states. The observed unsaturated magnetization, even at large applied fields, confirmed the high degree of spin-canting due to the existence of Yafet-Kittel spin arrangement. [ABSTRACT FROM AUTHOR]

Biosynthesis of silver nanoparticles has received considerable attention due to their cost-effective, eco-friendly and medicinal values. In this study, silver nanoparticles (Ag NPs) were synthesised using the aqueous leaf extracts of Piper nigrum. TEM images revealed that the particle is spherical with 20–50 nm in size. Furthermore, to evaluate the toxicity of synthesized Ag NPs, fish Labeo rohita were exposed to two different concentrations (2.5 µg/L as the treatment I and 5 µg/L as treatment II) for 35 days, and antioxidant parameters and histology of gill, liver and kidney were examined. A biphasic response in the activity of glutathione S-transferases (GST) was observed in gill and liver of fish. GST activity in the kidney of fish was significantly increased when compared to control group. Glutathione reductase (GR) activity in organs/tissue of fish were found to be increased while peroxidase (POD) activity was significantly decreased. Histopathological changes such as hyperplasia, proliferation of epithelial cells and fusion of lamellae were observed in both the concentrations. In liver, necrosis, nuclear degeneration and dilation of sinusoids were observed. Subsequently, the representative effects of POD activity were assessed based on the Box–Behnken Equation, 3-D contour plot and ANOVA analysis through response surface methodology analysis. [ABSTRACT FROM AUTHOR]

Evolution of 3D nanostructures is luring a great deal of importance owing to their eccentric structures that create plenty of rooms to grasp massive volume of charges. Here, a distinct multifunctional binder-free flexible electrode is developed by arrays of flower-like β-NiS nanostructures over flexible carbon cloth ( β-NiS@CC) by the in situ hydrothermal method. It unveils an ultimate areal capacity of 1.654 C cm-2 (827 C g-1) at 1 mA cm-2, which seems to be the highest among the reported NiS so far. The fabricated flexible supercapattery gadget delivers a remarkable energy density of 38 µWh cm-2 at a power density of 800 µW cm-2. Due to immense mechanical strength and resilience of 3D flower-like morphology, it is further exposed as an economical bifunctional electrocatalyst. Both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) exhibit a significant burst of the enormous quantity of gas bubbles at the low overpotentials of 320 and 278 mV, respectively, to achieve a current density of 20 mA cm-2. Further, the developed laboratory scale water electrolyzer offers a low cell voltage of 1.65 V to accomplish a water-splitting current density of 10 mA cm-2. Henceforth, the multifunctional 3D flower-like β-NiS electrode is demonstrated by defining its potential use in real-world appliances. [ABSTRACT FROM AUTHOR]

Abstract: To realize the ideal electrode material for supercapacitors, the scientific community has been prompted to investigate a variety of materials. This study deals with the hydrothermal synthesis of NiSb2O4 for the first time for application to hybrid supercapacitors. First‐principles density functional theory (DFT) calculations are employed to study the electronic structure of synthesized NiSb2O4. The single phase tetragonal structure NiSb2O4 is revealed from X‐ray diffraction (XRD) analysis. Rod‐like micron‐sized structures are revealed through field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Structural parameters and unit cell dimensions are deduced from Rietveld refinement analysis. The comparative effects of various K+ electrolytes (1 M KOH, 1 M KCl, 1 M KNO3 and 0.5 K2SO4) on the NiSb2O4 negative electrode material are studied. Cyclic voltammogram (CV) showed greatest specific capacitance of 758 F g−1 at 2 mV s−1 in 1 M KOH. Galvanostatic charge‐discharge analysis (GCD) exhibited capacitance of 382 F g−1 at 1 A g−1. The asymmetric supercapacitor is assembled with synthesized Ni3(Fe(CN)6)2(H2O) as positive electrode and the device exhibits a specific capacitance of 344 F g−1 at 1 mV s−1 in 1 M KOH in the wider potential window of 1.6 V, suggesting its potential application as an energy storage device. [ABSTRACT FROM AUTHOR]