The current study focuses on the rational design and comprehensive evaluation of a PVDF-HFP/PEG/MnO2 (PHP-M) composite membrane engineered to deliver multifunctional performance for electrochemical and biomedical applications. The prepared MnO2 filler and the PHP-M membrane were systematically characterized to assess their physicochemical properties. Particular emphasis was placed on understanding the synergistic interplay between PEG and MnO2 within the PVDF-HFP host matrix and its influence on the overall functional performance. FESEM analysis confirmed the uniform dispersion of MnO2 fillers throughout the polymer blend matrix, which contributed to high thermal and mechanical stability (27.7 MPa), along with remarkable oxidative resistance. Electrochemical investigations (EIS, LSV, and CV) revealed that the ionic conductivity of the membrane is on the order of 1.8 +/- 0.4 & times; 10(-4) S cm(-1) with a wide electrochemical window up to 1.8 V. These characteristics substantiate its applicability as a solid polymer electrolyte for proton-based energy storage systems. Oxidative stability studies along with the postreaction structural and electrochemical characterizations further verified the active participation of reactive oxygen species (ROS) in oxidative environments, reflecting the adaptive redox behavior of the membrane. From a biomedical perspective, the PHP-M membrane possessed superior antioxidant properties, with a radical scavenging efficiency of 58.2%. In parallel, antibacterial studies showed a significant inhibition zone of 25 mm against Escherichia coli and 18 mm against Staphylococcus aureus bacteria, confirming its strong antimicrobial performance. In vitro degradation and cytotoxicity analyses established the biocompatibility of PHP-M, reinforcing its potential for biomedical applications. These findings position PHP-M as a promising multifunctional material for integrated electrochemical and biomedical systems.
Development of efficient, cost-effective, and multifunctional electrocatalysts is the key focus in renewable energy research. Cobalt-based electrocatalysts are widely used in the electrochemical HER, OER, and ORR. In this study, we report a novel multifunctional electrocatalyst composed of polyaniline (PANI) decorated with cobalt nanoclusters, synthesized via a simple solvothermal method. The uniform distribution of amorphous cobalt nanoclusters within the PANI matrix provides abundant active sites, high electrical conductivity, and high surface area, resulting in excellent trifunctional electrocatalytic activity. The Co60@PANI catalyst exhibits a high half-wave potential of 0.74 V versus RHE and limiting current density of -4.82 mA cm-2 in 0.1 M KOH for the ORR. The catalysts also achieve low overpotentials of 292 and 320 mV at 10 mA/cm2 for HER and OER, respectively, in 1 M KOH. This finding provides a foundation for the development of highly efficient and multifunctional electrocatalysts toward energy conversion processes.
This study is focused on the deposition of Fluorine-doped ZnO (FZO) thin film on borosilicate glass substrate by spray pyrolysis technique and the influence of post-deposition annealing condition (air and vacuum) on its structural, morphological, optical and electrical characteristics. F concentration is maintained at 15 at.
This investigation focuses on the role of cerium(Ce) incorporation in modifying the structural features as well as the magnetic and ferroelectric responses of BiFeO3 (BFO) nanofibers fabricated using electrospinning. The XRD results confirmed that the Ce-substituted BFO nanofibers retain a distorted rhombohedral perovskite structure (space group R 3 & strns; c). Field emission scanning electron microscope analysis revealed that Ce incorporation reduces the nanofiber diameter, while crystallinity of the nanofibers was verified by high-resolution transmission electron microscopy. X-ray photoelectron spectroscopy measurements showed the oxidation states of the Ce-doped fibers. Magnetic characterization demonstrated a progressive improvement in magnetic properties with increasing Ce content, reaching an optimum at 10% Ce doping, which yielded a magnetic saturation of 2.85 emu g-1. Ferroelectric testing further revealed improved polarization at 10% Ce doping, with a saturation polarization of 0.528 mu C cm-2. Overall, these results highlight Ce-doped BFO nanofibers are viable options for applications involving next-generation multiferroic memory devices.
Statistical dependence and stochastic orders are two common tools used in distribution theory or, broadly speaking, reliability theory. In the context of the present work, we draw attention to the fact that reliability practitioners usually assume that the components constituting a system work independently. However, there are instances where the components are found to be stochastically dependent following a certain multivariate distribution. This gives rise to some error in computation of aging functions. In this paper, we propose a method based on statistical dependence and stochastic orders to compute the error incurred due to the faulty assumption that components are independently working. Our method makes the task of error analysis readily comprehensible. Earlier, the authors working in this direction considered some bivariate distributions and inferred about over/under assessment (OA/UA) of aging functions in silos, viz., survival function (SF), hazard rate, mean residual life function. However, in our work, we propose that OA/UA in the SF is closely related to statistical dependence, and OA/UA in some specific aging functions can be inferred with the help of stochastic orders, assuming that the orders for some other class of aging functions are known.
