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This poster was presented at the 2024 UCSB EEMB Research symposium.This project investigates how water quality metrics correlate with seasonal changes in algal and aquatic vegetation abundance via close-range and satellite imagery analysis at the Devereux Slough. The Devereux Slough, part of UCSB’s North Campus Open Space (NCOS), is a temporary open/closed estuary undergoing restoration efforts following its previous use as a golf course. The Devereux Slough provides buffer area for storm surges and sea level rise, and it functions as a wildlife corridor linking protected lands. The Aquatic Invertebrate Lab at the NCOS evaluates wetland function in terms of nutrient filtering and support for wildlife. We analyze the effects of restoration on the ecosystem, abiotic factors on aquatic food webs, and the relationship between nutrient pulses and algal blooms. We deployed camera stands at bridges across NCOS to research algal growth through photography where Coastsnap is used to catalog images taken by citizen scientists. We then use ENVI and Adobe Photoshop to divide photographs into quadrats and analyze the algal cover based on pixel cover. We have Solinst leveloggers deployed near each site which collect water level, temperature, and in some cases, conductivity. We also investigate how aquatic vegetation density shifts spatially and temporally at the Devereux Slough from 2022-2024. We isolate spectral bands from monthly PlanetLabs satellite imagery and apply the normalized difference aquatic vegetation index function in R. We are interested in how plant health varies between longer- and shorter-term restoration sites and with water quality metrics taken by Solinst leveloggers.

New materials based on LaScO 3 , namely, were synthesized by the solid-phase method. The structure of the resulting complex oxides was refined. The electrical properties of the undoped, mono- and co-doped samples were determined by varying the temperature T and pH 2 O. All substituted samples were found to have the conductivity of several orders of magnitude higher relative to the parent phase. The maximum conductivity was observed for the Ba2+/Mg2+-co-doped sample due to high concentration of oxygen vacancies The possibility of phase formation and its electrical properties are greatly influenced by geometric parameters such as the ratio of the radii of the host- and the dopant-ion, the free cell volume, the critical radius. It has been demonstrated that the nature of the dopant affects the porosity of the samples. The investigated phases demonstrate good chemical stability in a CO 2 -saturated atmosphere. [Display omitted] [ABSTRACT FROM AUTHOR]

Searching for suitable materials for symmetrical solid oxide fuel cells is an essential direction in modern high-temperature electrochemistry. One promising option for symmetrical electrode materials is a family of Fe-based complex oxides, which have high mixed ionic and electronic conductivity. This study focuses on the synthesis and thorough evaluation of the Pr 1–x Ba x FeO 3–δ (x = 0.4, 0.5, 0.6) materials as symmetrical electrodes for proton ceramic electrochemical cells. The functional properties of these phases, both in powder and ceramic forms, are investigated for the first time under oxidizing and reducing conditions. The obtained results indicate that a low Ba-content is preferable for achieving high redox stability, low thermal expansion, and high conductivity of ferrite-based perovskites. However, Ba-enriched samples exhibit the lowest polarization resistance, particularly in reducing atmospheres. This may be due to the easier exsolution of Fe-metallic particles with high electrocatalytic activity. Therefore, a certain compromise needs to be achieved considering the obtained experimental data in a complex form. This work provides a basis for designing symmetrical electrodes by offering comprehensive information on the functional properties of ferrites in both oxidizing and reducing conditions. [Display omitted] • Pr 1–x Ba x FeO 3–δ (PBxF, x = 0.4, 0.5, 0.6) materials were synthesized and characterized. • Functional properties of PBxF were analyzed under oxidizing and reducing conditions. • PB0.4F exhibits the highest redox stability and lowest TEC values. • However, the PB0.6F electrodes show the highest electrochemical activity. • A trade-off between the functional properties is needed for real PBxF applications. [ABSTRACT FROM AUTHOR]

Ca and Cs doped barium titanate lead-free ceramic with the formula Ba 0.75 Ca 0.2 Cs 0.05 TiO 3 has been prepared by the solid-state reaction method. X-ray diffraction (XRD) confirms the crystallization of the sample in a tetragonal structure with a P 4 mm space group. The phase purity and grain morphology were evaluated using X-ray diffraction and scanning electron microscopy (SEM). The material exhibits a primary phase of Ba0.75Ca0.2Cs0.05TiO3 with a minor secondary phase of BaO 2 , and the average grain size is determined to be 1.66 μm. Using non-destructive complex impedance spectroscopy (CIS), we extensively studied the electrical behavior, including complex impedance (Z*), complex modulus (M*), electrical conductivity, and relaxation mechanisms, of Ba 0.75 Ca 0.2 Cs 0.05 TiO 3 over a wide temperature (85 K–290 K) and frequency range. The ac conductivity analysis reveals that the dominant conduction mechanism is the non-overlapping small polaron tunneling (NSPT) model. The impedance analysis indicates a single semi-circle in the real and imaginary parts, suggesting a single relaxation mechanism. Additionally, the activation energy was calculated to be approximately 0.0489 eV. These findings contribute to the understanding of the structural and electrical properties of Ba 0.75 Ca 0.2 Cs 0.05 TiO 3 , highlighting its potential applications in electronic devices such as capacitors, thermistors, and ferroelectric random access memories (FRAMs). [ABSTRACT FROM AUTHOR]

This study presents, for the first time, a new method for the synthesis of polymers containing different ratios of oxidized quinoid and reduced benzenoid units in polyaniline (PANi)‐like structure. Copolymers were synthesized by an oxidative copolymerization method of p‐phenylene diamine (p‐PDA) and o‐anisidine (o‐An) in an organic medium using different initial compositions of monomers. The compositions of the copolymer were determined based on 1H NMR spectral data. The thermal stability, electrical conductivity, morphology, and solubility were studied and a comparative analysis with polyaniline and corresponding homopolymers was been carried out. The thermal behavior of copolymers was studied using thermogravimetric analysis and differential scanning calorimetry. It was found that during heating one endothermic process of water evaporation and two exothermic processes occur, which depend on copolymer composition, and only 30% weight loss occurs up to 600 °C. It is shown that room‐temperature conductivity of copolymers doped with hydrochloric and sulfuric acids ranges from 10−5 to 10−3 S cm−1 and increases with increasing concentration of o‐anisidine structural units. The conductivity of iodine‐doped copolymers is of the same order as the conductivity of iodine‐doped PANi in emeraldine and leucoemeraldine forms. The morphology of doped copolymers depends on the co‐monomer ratio and the type of dopants. [ABSTRACT FROM AUTHOR]

Highlights This study evaluated the percolation threshold in polymer nanocomposites and its dependence on the aggregation/agglomeration phenomenon. The main objective of the investigation was to propose a particular method that besides revealing the impact of different involved parameters on the percolation threshold could also provide useful information regarding the system characteristics. In line with that, a specific geometrical structure was employed to represent the clusters and assess the variation of the percolation threshold and characteristics of the polymer/particle interphase region. The findings were applied in an improved form of the percolation theory to perform validation against the related experimental data. Improvement was conducted by involving the impact of the newly estimated percolation threshold, aggregations/agglomerations, interphase region, and so forth. Also, specific theories were employed to define the electrical conductivity of the nanoparticle clusters and interphase region. The results showed that the percolation threshold is directly affected by the content of the nanoparticles and the characteristics of the aggregates/agglomerates. Besides, it was revealed that parameters, such as the size of nanoparticles, physical characteristics of the polymer matrix and interphase region, dispersion quality, etc. may substantially affect the percolation threshold and subsequently other physical properties of the system, such as electrical conductivity. A structural approach toward understanding the percolation phenomenon. Defining the particular dependence of percolation threshold on dispersion quality. Estimating the content of aggregates/agglomerates using percolation theory. Improving the percolation theory to predict the electrical conductivity. Applying the scaling theory to define the electrical conductivity of the interphase. [ABSTRACT FROM AUTHOR]

The Gd and Zr co-doped ceria electrolyte Gd 0.1 Ce 0.9- x Zr x O 1.95 (x = 0, 0.03, 0.06, 0.09, 0.12, 0.15, labeled as GDC, Zr0.03GDC, Zr0.06GDC, Zr0.09GDC, Zr0.12GDC, Zr0.15GDC) was synthesized by solid-state reaction. The XRD and Rietveld refinements reveal that Zr x GDC is in a cubic fluorite phase with the cell parameters a decrease from 5.4186(1) to 5.3728(1) Å and cell volume V decreases 159.10(2) to 155.09(2) Å3 as the x increases from 0 to 0.15. SEM studies confirm a dense microstructure with well-defined grains in a size of 10–20 μm. The Raman spectra agree with the fact that a solid solution is formed and the blue-shift of Raman modes is observed as expected. XPS analysis shows that Ce4+ is more stable in Zr doped GDC. The conductivity of Zr0.03GDC reaches 1.2 × 10−3 S/cm at 450 °C. The bond valence of Ce4+ is constrained to a higher one as the Ce4+ is substituted by Zr4+ in the solid solution, and a higher stability in the reducing atmosphere was achieved. The electronic conductivity decreases from 14.8% of GDC to 0.1% of Zr0.03GDC at 400 °C. The oxygen ion transference number of Zr0.03GDC is improved significantly to > 0.93 in 3% H 2 /Ar at 700 °C. [ABSTRACT FROM AUTHOR]

To better understand the variations in physical, mechanical, and electrical properties, (Ge 2 S 8) 100-x Te x chalcogenide glasses have been synthesized. These glasses encompass a composition range of 0 ≤ x ≤ 12. The mechanical properties have been studied by determining the longitudinal (ν L) and transverse (ν T) ultrasonic velocities. A network structure evaluation with composition has been performed via parameters like coordination number (< N r >), crosslinking density (D CL), glass transition temperature (T g), etc. Also, the elastic parameters trend values have been associated with the decrease in the cohesive energy value of the system. An overall physical analysis of the Ge-S-Te systems reveals that the system's rigidity and the cross-linking density are decreasing. Within the temperature range of 300–420 K, the temperature dependency of the dark conductivity and photoconductivity has been investigated. The intensity-dependent photoconductivity is governed by a power law, with intensity (I ph = G δ ) with δ lying between 0.5 and 1. The photosensitivity values reveal that the glassy system may be suitable for applications in optoelectronic devices. A correlation among the parameters has been established by calculating elastic parameters and conductivity measurements and evaluating the network structure theoretically. The present efforts clarify the composition-structure dependence and relationship in the Ge-S-Te glass series. [ABSTRACT FROM AUTHOR]

The present research article demonstrates the dispersion of boehmite (BHM) nanoparticles into sericin (SER) from silk industry waste with polyvinyl alcohol (PVA) to enhance the optical, mechanical, thermal and electrical characteristics of PVA/SER blend nanocomposites prepared by a simple green synthesis. Techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV visible spectroscopy, field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were carried out for the characterization of the prepared composites. XRD revealed the increased crystallinity of the polymer blend by the reinforcement of BHM. The existence of intermolecular interactions in the blend composite was confirmed by FTIR and UV spectroscopy. The optical bandgap energy of the biopolymer blend decreases with the inclusion of BHM. The SEM and HR-TEM confirmed the homogeneous dispersion of BHM in the blend at 5 wt% loading. The glass transition temperature and thermal stability of the blend nanocomposites were significantly improved by the inclusion of BHM was deduced from DSC and TGA. The dielectric constant and AC conductivity were remarkably increased with the reinforcement of nanoparticles. The activation energy obtained from AC conductivity decreased with temperature. The mechanical properties of the blend nanocomposites (hardness, tensile strength and Young's modulus) were greatly increased in presence of BHM. The 5 wt% sample has the highest tensile strength, Young's modulus, dielectric constant, AC conductivity and optical properties, allowing it to be used to make optoelectronic devices with better charge-storing capacity and flexible-type electrochemical gadgets. [ABSTRACT FROM AUTHOR]

Poly(oxyethylene) (POE) is frequently used as suitable component to prepare solid polymer electrolytes (SPEs), due to its: (i) ability to coordinate and dissociate doping salts; (ii) good mechanical properties; and (iii) high chemical and electrochemical stability. With the aim to obtain calcium secondary batteries, here we describe the preparation and studies of crosslinked Ca‐polycondensate (NPCY) electrolytes with formula NPCY/(CaTf2)x based on fragments of POE chains and CaTf2. The molecular weight of POE precursors is Y=400 and 1000 g ⋅ mol−1. The effect of POE molecular weight on the thermal, structural, and electrical properties of NPCY/(CaTf2)x is investigated revealing that in mesoscale this materials show: (i) two different nanodomains with polyether chains both "free" (not coordinating the cation) and involved in 4–4 coordination cages of Ca2+ metal ions; (ii) fα‐fast, fα‐cross and fα‐slow relaxation modes of polyether chains, detected by broadband electrical spectroscopy, which are coupled with the long‐range charge migration pathways of SPEs; (iii) that triflate (Tf−) anions, which act as plasticizers, modulate the inter‐chain migration processes of Ca2+ between polyether coordination sites. Finally, the conductivity values of NPCY/(CaTf2)x, which is up to 10−4 S ⋅ cm−1 at 80 °C, classify NPCY/(CaTf2)x as promising SPEs for the development of calcium secondary batteries. [ABSTRACT FROM AUTHOR]

Researchers are now avoiding perovskite materials containing lead due to their toxicity and instability in open air and heat. In this study, our research group worked on potassium-based K2MgSiCl6 & K2MgSiBr6 perovskite compounds and thoroughly investigated these materials' basic behaviours. Goldschmidt and formation energy results certify the structure and thermodynamic stabilities of the studied compounds. The band gaps noted for the K2MgSiCl6 & K2MgSiBr6 perovskites were 2.42 eV & 1.88 eV, respectively. After the mechanical observations of the investigated compounds, it became apparent that both the studied compounds own brittle and anisotropic nature. Based on the tendency to absorb electromagnetic radiations both in the ultra-violet and visible range, it enables the K2MgSiCl6 & K2MgSiBr6 perovskites suitable for detectors, solar cells, and many other optoelectronic devices. The K2MgSiBr6 material showed the first response to the electromagnetic radiations in the visible range and acquired the optical conductivity value of 1219 (Ω.cm)-1; however, K2MgSiCl6 material showed its response to a bit higher energetic photons in the visible range than K2MgSiBr6 material, but its optical conductivity was higher (i.e., 1270 (Ω.cm)-1) than the K2MgSiBr6 material in the visible range. [ABSTRACT FROM AUTHOR]

The electronic transport properties of the bilayer graphene double layer (BLGDL) system at T = 0 K using the Boltzmann transport equation are reported here. The conductivity of the BLGDL system has been calculated with varying parameters as relative carrier concentration (n (c) / n (C I)) , short-range (point defect) and long-range (Coulomb charge) impurity concentration, relative dielectric constant (ε r) and interlayer distance (d). The maximum conductivity has been achieved in the absence of short-range impurity. The short-range impurity plays a non-trivial meaningful role in high dielectric and high carrier concentration regimes and limits the conductivity. For higher ε r and higher n (c) / n (C I) values, the nature of the conductivity curve turns out to be of a sublinear nature, while in all other cases, it shows a superlinear trend. Suitable selection of relative dielectric constants, relative carrier concentration and interlayer distance helps to improve the conductivity of the BLGDL system. If the dielectric constant of the spacer is higher than the substrate material, the thickness of the spacer material helps remarkably in enhancing conductivity. Moreover, a comparison of BLGDL with our previously reported MLG–MLG double layer graphene system (DLGS) confirms that higher conductivity is achieved in the case of BLG–BLG system compared to DLGS. [ABSTRACT FROM AUTHOR]

Graphene/Ag composite aerogels (GA/Ag) with three-dimensional hierarchical porous microstructure were prepared by in-situ formation of silver nanoparticles obtained from AgNO3 into the porous structure of graphene aerogel. When the used AgNO3 concentration was 12wt.%, the specific surface area of the obtained GA/Ag was 128.6m2g−1, which was higher than that of GA. GA/Ag exhibited electrical resistivity of 0.63Ω⋅cm and excellent microwave absorption property with the minimum reflection loss of −40dB at 10.9GHz with the corresponding effective absorption bandwidth of 4GHz (8.8–12.8GHz). The GA/Ag composite aerogels enabled multiple reflection loss and absorption of incident electromagnetic waves, realizing excellent microwave absorption effects based on impedance matching and efficient synergy. It could be predicted that GA/Ag with a hierarchical porous structure may show potential application prospects in the field of microwave absorption. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effects of the fiber orientation and the presence of resin-rich layers on electromagnetic induction testing (EIT) of carbon fiber reinforced thermoplastics (CFRTPs). First, a finite-element analysis was performed to evaluate the distribution and path of the eddy and displacement currents induced in interlaminar conductive and interlaminar non-conductive CFRTP specimens. Second, interlaminar electrically conductive and interlaminar non-electrically conductive specimens of unidirectional CFRTP and cross-ply laminated CFRTP were fabricated using a 3D printer, with control of the number of PA-6 layers and fiber orientation. EIT of the specimens revealed that the presence of resin-rich layers and fiber orientation affected the measured EIT output. The results also indicated that the EIT of CFRTP with resin-rich layers requires penetration of displacement currents between the layers. [ABSTRACT FROM AUTHOR]

UV sensors in wearables help outdoor users protect their skin by monitoring exposure. Detecting UV light is crucial for safety, given its potential hazards. Our research has developed an efficient methodology for creating UV sensors. This method is characterized by a streamlined, one-step solution-processed approach, prioritizing simplicity in fabrication, heightened responsiveness, and cost-effectiveness as key attributes. We designed a platform utilizing the synergistic effects of a hybrid network, incorporating the conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) and Zinc oxide (ZnO) low dimensional rods (LDR) at varying concentrations of ZnO relative to PEDOT: PSS. Using a straightforward drop-cast technique, the hybrid film was applied to a p-type silicon wafer. Incorporating ZnO LDR into PEDOT: PSS causes the LDR to become integrated into the polymer matrix, ultimately resulting in a consistently distributed film. A thickness profilometer was utilized to measure the thickness of the hybrid film, which was around 1.4 μm. FE-SEM was employed to elucidate the intricate morphological features of ZnO LDR and to investigate the synergistic hybrid composition formed by the combination of PEDOT: PSS and ZnO. The micrographs provided valuable insights into the size, shape, and distribution of ZnO LDR, facilitating a comprehensive understanding of their morphological characteristics. The length of the LDR, on average, was roughly 9.5 μm, and their diameter was approximately 0.575 μm. Furthermore, the formation of the hybrid film was verified using UV-Vis spectroscopy, revealing distinct bands originating from both PSS in PEDOT: PSS and ZnO. Upon UV radiation exposure to the hybrid film, conductivity changes were measured in both UV on and off conditions. The most successful device with 10 wt% of ZnO in PEDOT: PSS exhibited a response of around 7.5%. [ABSTRACT FROM AUTHOR]

With the escalating global energy demand, the exploration of alternative, easily accessible, and cost‐effective energy sources has become imperative. The diminishing reserves of conventional energy resources underscore the urgency to transition towards renewable energy. Solid polymer electrolytes (SPEs) have gained prominence for energy storage electrochemical devices due to their high flexibility and favorable electrode–electrolyte interactions. This study focuses on synthesizing nano cuprous oxide (CuO) semiconductors via the precipitation method. The prepared CuO nanofiller is homogeneously dispersed into a polymer electrolyte solution. Utilizing the solution cast method, free‐standing polymer electrolyte films are fabricated, exhibiting commendable mechanical stability. Polyvinyl alcohol (PVA) serves as the host material, with potassium iodide (KI) salt, forming the basis for the polymer electrolyte. The resultant electrolyte films underwent comprehensive characterization for their electrical and optical properties. The investigation aims to identify the optimal composition of the electrolyte film with superior conductivity. The selected composition will be employed in the fabrication of various electrochemical devices, demonstrating the potential for enhanced energy storage applications. This work not only contributes to the synthesis of advanced solid polymer electrolyte films but also paves the way for the development of efficient and sustainable energy storage solutions in the realm of renewable energy technologies. [ABSTRACT FROM AUTHOR]

The fuel cell carries the promise of being ecologically beneficial and being one of the renewable energy choices. Solid acids have super‐protonic behavior, allowing them to act as conductors. It can operate at high temperatures. Hydration, on the other hand, can be employed to increase the solid acid and performance. Furthermore, the size of the electrolyte membrane influences the conductivity, stability, and crystal structure of the fuel cell solid acid compounds. Very few studies have been conducted on solid acid fuel cells, which are still being researched in order to make them feasible as well as a trustworthy alternative to clean renewable energy. This review presents an outline of the variables or attributes and current challenges that influence the technical efficacy and performance of the unique super‐protonic conductors for solid acid fuel cells. [ABSTRACT FROM AUTHOR]

The decline in fossil fuels on the earth has become a primary global concern which has urged mankind to explore other viable alternatives. The exorbitant use of fuels by an ever-increasing global population demands a huge production of energy from renewable sources. Renewable energy sources like the sun, wind, and tides have been established as promising substitutes for fossil fuels. However, the availability of these renewable energy sources is dependent on weather and climatic conditions. Thus, this goal can only be achieved if the rate of energy production from renewable sources is enhanced under favorable weather conditions and can be stored using high energy storing devices for future utilization. The energy from renewable sources is principally stored in hydropower plants, superconducting magnetic energy storage systems, and batteries. [ABSTRACT FROM AUTHOR]

In this study, in order to determine the effect of matrices' shape on the percolation threshold values, computer simulations were performed using the Monte Carlo method for a 200 × 200 square-shaped matrix and rectangular matrices containing the same number of nodes as the square matrix. Based on the simulations, the average values of the percolation thresholds and standard deviations for the current flow along and across the matrices were determined. It was determined that for a square-shaped matrix, the average values of the percolation thresholds in both directions of the current flow were the same. Extending the rectangular matrix while reducing its height causes the average value of the percolation threshold in the direction of the current flow along the matrix to increase from 0.592740 to 0.759847, while in the transverse direction, it decreases from 0.592664 to 0.403614. The values of the classical asymmetry coefficients of the probability distributions of the percolation thresholds for both directions of the current flow were determined. Histograms of the probability distributions of the percolation threshold values for a square-shaped matrix and rectangular matrices were made and compared with the normal distributions. It was found that the occurrence of two percolation thresholds in rectangular layers should be considered when analyzing the electrical conductivity measurements of nanocomposite thin films. [ABSTRACT FROM AUTHOR]

In this paper, flexible conductive composite materials were prepared from flexible graphite and carbon fiber by mould pressing, and their micromorphology was studied by SEM. The influence of carbon fiber content on the mechanical properties and electrical conductivity of the flexible conductive composite material was studied, and the corrosion rate of the flexible conductive composite material coupling with galvanized steel in soil with different SO42− concentrations was studied. The results showed that the tensile strength reached 5.82 MPa when the mass ratio of carbon fiber to flexible graphite was 1:20, and the volume resistivity achieved 4.76 × 10−5 Ω·m when the mass ratio of carbon fiber to flexible graphite was 1:30. With the increase in molding pressure, tensile strength and electrical conductivity had a slight increase. When the flexible conductive composite material was coupled with galvanized steel, sulfate could accelerate the galvanic cell corrosion between the flexible graphite grounding material and galvanized steel. The increase in the sulfate concentration led to more corrosion acceleration. With the increase in corrosion time, the corrosion potential of the flexible graphite grounding material and galvanized steel coupling body decreased to its lowest at 30 days, and then increased gradually. The corrosion current was the highest at 30 days, and then decreased gradually. [ABSTRACT FROM AUTHOR]

Iron microparticles were coated with polypyrrole in situ during the chemical oxidation of pyrrole with ammonium peroxydisulfate in aqueous medium. A series of hybrid organic/inorganic core–shell materials were prepared with 30–76 wt% iron content. Polypyrrole coating was revealed by scanning electron microscopy, and its molecular structure and completeness were proved by FTIR and Raman spectroscopies. The composites of polypyrrole/carbonyl iron were obtained as powders and characterized with respect to their electrical properties. Their resistivity was monitored by the four-point van der Pauw method under 0.01–10 MPa pressure. In an apparent paradox, the resistivity of composites increased from the units Ω cm for neat polypyrrole to thousands Ω cm for the highest iron content despite the high conductivity of iron. This means that composite conductivity is controlled by the electrical properties of the polypyrrole matrix. The change of sample size during the compression was also recorded and provides a parameter reflecting the mechanical properties of composites. In addition to conductivity, the composites displayed magnetic properties afforded by the presence of iron. The study also illustrates the feasibility of the polypyrrole coating on macroscopic objects, demonstrated by an iron nail, and offers potential application in the corrosion protection of iron. The differences in the morphology of micro- and macroscopic polypyrrole objects are described. [ABSTRACT FROM AUTHOR]

In this article, the properties of Cs2Pb2O3 have been investigated using the first‐principles method. It covers the relevant structural, stability, electronic properties, conductivity, and optical properties. The phonon spectra and elastic properties analysis show the stability of Cs2Pb2O3, band structure, density of states, charge density diagram, and bond populations are analyzed to show the electronic structure of the system more clearly. The calculated results indicate that considering spin‐orbit coupling (SOC) will reduce the band gap. The charge density diagram and bond populations indicate that the Cs–O bond is mainly ionic and the Pb–O bond is mainly covalent and partially ionic. The analysis of optical properties indicates good transparency, and the calculated hole mobility is 10.88 cm2 V−1 s−1, suggesting that it is a promising p‐type conductive oxide. [ABSTRACT FROM AUTHOR]

The enormous interest in developing powerful Li‐based batteries leads to a boost in materials research. Though Li–sulfur batteries offer very high energy densities, the nature of Li‐ion dynamics in the final discharge product Li2S$\left(\text{Li}\right)_{2} \text{S}$ has not been fully understood yet. While nanocrystalline Li2S$\left(\text{Li}\right)_{2} \text{S}$ shows enhanced ion dynamics compared to its coarse‐grained counterpart, the interaction of Li2S$\left(\text{Li}\right)_{2} \text{S}$ with another binary such as LiI seems to be rather unexplored. Herein, an equimolar mixture of Li2S$\left(\text{Li}\right)_{2} \text{S}$ and LiI is treated in a high‐energy ball mill, and both the overall and local structural changes are studied by X‐ray powder diffraction and 6,7Li$^{6,7} \text{Li}$ nuclear magnetic resonance (NMR), respectively. Besides the formation of amorphous regions, evidences are found for the generation of anion‐mixed sites that give rise to facile Li+$^{&amp;amp;amp;amp;amp;amp;amp;amp;amp;plus;}$ exchange on the 2D exchange NMR timescale. Compared to a coarse‐grained reference sample, the overall (bulk) ionic conductivity of nanocrystalline Li2S$\left(\text{Li}\right)_{2} \text{S}$‐LiI increases by two orders of magnitude. Besides the anion‐mixing effect, this increase benefits from nanosize effects that include the formation of defect‐rich interfacial regions. NMR relaxation measurements fully support this result and reveal heterogeneous dynamics with lower activation energies for both the localized hopping processes and long‐range ion transport in nm‐sized Li2S$\left(\text{Li}\right)_{2} \text{S}$‐LiI. [ABSTRACT FROM AUTHOR]

Conductive biohydrogel received prominent application in the diverse field. Hydrogel based on biopolymer is generally biocompatible and degradable but exhibiting poor conductivity. To enhance the conductivity of biohydrogel, composite of bioplomer and synthetic polymer are preferred. This work aims to prepare such composite for the augmentation of conductivity of biohydrogel. Gum Ghatti (GG), a natural biopolymer, was grafted with polyacrylic acid and subsequently cross-linked to form a hydrogel. The synthesized hydrogel was then infused with oxidized multiwalled carbon nanotubes (-o-MWCNTs). The materials underwent comprehensive characterization using techniques, such as FT-IR, XRD, SEM, and TGA-DTA. The grafted GG demonstrated a synergistic blend of biopolymer and polyacrylic acid (AA) properties. The hydrogel's electrical conductivity was systematically investigated at varying loadings of -o-MWCNTs within the GG-cl-P(AA) matrix. As the loading of -o-MWCNTs increased from 10 to 30 mg, there was a notable enhancement in electrical conductivity. However, at higher loading amounts, the electrical conductivity exhibited a subsequent decline. [ABSTRACT FROM AUTHOR]

[Display omitted] The creation of three dimensional (3D) structures out of two-dimensional (2D) materials while retaining their extraordinary mechanical and transport properties after processing is one of the current great challenges in materials sciences (Ruoff, 2008; Kong et al., 2019; Lin et al., 2019). Guided by density functional theory (DFT) and molecular dynamics (MD) simulations we found a successful route for a sustainable production of 3D metallic carbon materials that are synthesized from pristine 2D graphene flakes with hydrolyzed edges. The edge hydrolysis lead to strong geometrical anisotropy and self-organization in solution before processing. After processing we obtain a 3D carbon structure where 2D graphene flakes are crosslinked by carbon chains with aromatic groups at very mild annealing temperatures (∼150 °C), eliminating the constraints for achieving the in-situ preparation of conductive carbon structures. These 3D carbon structures preserve microscopic order but are macroscopically disordered, presenting physical properties of anisotropic metallic carbon with large Young modulus (E ≈ 20 GPa), and room temperature thermal (k ≈ 180 W/mK) and electrical (σ ≈ 300 kS/m) conductivities comparable to ordinary metals. [ABSTRACT FROM AUTHOR]

A copper fluoride with small size and high purity is very important to present its ability as a cathode material for lithium thermal batteries (LTBs). In this paper, we investigate the effect of the heat treatment temperature of the precursor ammonium copper fluoride on the preparation of a high-performance copper fluoride cathode. The color of CuF2 gradually changes from white to dark brown as the heat treatment temperature of the ammonium copper fluoride precursor is increased due to the change in dimensions and morphology. The CuF2-250 prepared at the heat treatment temperature of 250 ℃ has a small D50 particle size of 1.838 µm (agglomeration of particles from 50 to 100 nm), high purity, large BET surface area of 16.3649 m2/g, and excellent working properties. Its operating voltage reached as high as 3.5 V in the initial activation stage at a discharge current density of 500 mA/g, which is attributed to the better conductivity caused by its small size favorable shortened Li+ diffusion path, and its specific capacity and discharge time at the cut-off voltage of 1.5 V were 498 mAh/g close to 94% of the theoretical specific capacity (528 mAh/g) and ultralong 3585 s, respectively. This study provides a guideline for the development of high-performance cathode materials for LTBs. [ABSTRACT FROM AUTHOR]

BACKGROUND: The oil industry has a big impact on the environment by itself and by using chemically synthesized surfactants. Biosurfactants are an ecofriendly alternative, especially rhamnolipids produced by Pseudomonas aeruginosa. Rhamnolipids in a determined concentration decrease the liquid surface tension, and this allows access oil hydrocarbon to be degraded. The objective of this research is to characterize the biosurfactant produced by the native strain P. aeruginosa 6K‐11 by determining its critical micelle concentration (CMC), Krafft point, and emulsifying activity. RESULTS: Experiments were initially performed with rhamnolipid produced by P. aeruginosa 6K‐11 growing on Siegmund‐Wagner medium with 1% of waste oil as carbon source and at 31.26 °C, 186 rpm after 42 h of incubation. After that, the biosurfactant was purified according to acid precipitation methodology. The first conductivity measurement, 34 μS/cm, was obtained with 12.5 g/L of rhamnolipid by using an APERA conductivity meter. The rhamnolipid CMC was 5.86 g/L due to the conductivity measurements graph and 0.49 was the dissociation degree. The equations of both lines were found by the method of least squares. The rhamnolipid has produced 1.97 Units of Emulsifying Activity (UEA) and 50% stability was observed based on the E24 Index. The highest conductivity achieved under 39 °C, as calculated from a conductivity against temperature graph, was the Krafft point. CONCLUSION: These findings give important parameters to characterize the P. aeruginosa 6K‐11 biosurfactant activity that can be used to accelerate oil biodegradation in bioremediation processes. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Eastern Continental shallow lakes are specific with their higher nutrient concentration compared to other lentic water bodies with similar specifications. Nonetheless, their phytoplankton and macrophyte assessment systems used more often than others within state monitoring programs, are weakly influenced by nutrient concentrations, unlike all other lake types in Europe. In this study, we used all available data for Eastern Continental shallow lakes on the Black Sea coast of Bulgaria from the state monitoring for 14 years (2008-2021). The goal was to find how environmental variables influence the ecological status assessment by phytoplankton and macrophyte-related indices. Likewise, it was important to understand the studied parameter's interrelations within Dourankoulak Lake and the lake complex Shabla-Ezerets. The most important environmental parameters were determined with principal component analysis since it helps find the hidden relationships. Afterwards, those variables were used for univariate linear regression testing because of its simplicity and reliability. The aim was to find the best-suited parameters for the ecological status explanation by different biological indices, which can be used for further predictions of the ecosystem condition. In addition, nitrogen--phosphorus dependency, where possible was investigated, confirming conclusions from mesocosms studies from water bodies with similar characteristics. The algae group index or the so-called "Catalán Index", in its original form of representing results and considering its ecological quality ratio values, was influenced by conductivity concentrations the most in Ezeretsko Lake and weaker at Dourankoulak Lake. Nutrient relationship with biological quality elements was not found, confirming results on a European level. In Shablensko Lake a dose-dependent relation between nitrates and phosphates was found, which shows that augmenting the quantity of nitrogen is related to the increasing concentration of phosphates. [ABSTRACT FROM AUTHOR]

A search for an optimum technique for studying the electrical characteristics of thin n/p-InxGa1–xAs semiconductor layers with different doping levels has been carried out. The primary task has been to measure the main electrical characteristics by different methods using resistivity (conductivity), majority carrier concentration, dependence of the main electrical parameters on the doping type and level, and their comparison. Using the example of the p- and n-In0.01Ga0.99As solid solutions grown by MOCVD, a technique for studying the main electrical characteristics of the epitaxial layers has been proposed, which takes into account the estimated homogeneity on large-area samples. Results obtained by different methods, including photoluminescence, contactless surface resistivity measurement, van der Pauw (Hall effect), electrochemical capacitance–voltage profiling, and in situ control, have been compared. Basing on the results obtained and comparison with the literature data, conclusions have been drawn concerning the need, sufficiency, and complementarity of the methods for controlling and studying semiconductor epitaxial structures. [ABSTRACT FROM AUTHOR]

The cathode material of Na2/3Ni1/3Mn2/3O2 composition (NNMO) was obtained by the carbonate coprecipitation followed by solid-phase reaction and characterized by XRD analysis, ICP-MS, and electron and impedance spectroscopy. NNMO crystallizes in a P2-type layered hexagonal structure (sp. gr. P63/mmc), consists of spherical agglomerates of ~ 1–3 microns in size, and forms from the plate-like primary grains. The NNMO ionic conductivity value at room temperature was 1.8*10−4 and 1.3*10−4 S cm−1 when measured perpendicularly and parallel to the compression axis, respectively. The estimated in dc mode values of electronic conductivity were by 2–3 orders of magnitude less than ionic conductivity. The obtained materials were tested as cathodes in sodium-ion battery cells versus sodium metal. The discharge capacity of NNMO was 160 mAh g−1 and 86 mAh g−1 in the potential range of 1.5–4.0 V and 2.3–4.0 V, respectively (20 mA g−1). NNMO was shown to be stable under cycling in the potential range of 2.3–4.0 V. [ABSTRACT FROM AUTHOR]

Using non-renewable resources in energy storage has spurred the development of supercapacitors, widely applied in electric vehicles and portable electronic devices for their swift charge–discharge cycles and high-power density. Depending on their materials and energy-storage methods, supercapacitors are classified as either electrochemical double-layer capacitors or pseudocapacitors. This study synthesizes a bis(dimethyl pyridine oxalic acid)oxalate (BDPO) and evaluates its electrochemical properties through impedance analysis. The results reveal promising performance, with specific capacitance values peaking at 330.52 g/F. Scan rate optimization at 0.05 V/s proves crucial for the supercapacitor system's highest efficient charge storage capacity. Additionally, structural confirmational analysis is done by optimized geometry, NMR analysis, and vibrational analysis also interactions are confirmed through ELF, LOL, AIM, and NBO analysis. Following an NBO assessment, crucial donor–acceptor interactions were examined. Notably, with stabilization energies of 33.36, 22.59, 10.24, 3.24, 1.73, 1.18, and 1.09 kcal/mol are caused by hyperconjugative contacts in lone pair LP (O35) → σ*(N14—H15), LP (O41) → σ*(N29—H42), LP (O40) → σ*(O33—H34), LP (O43) → σ*(C1—H2), LP (O48) → σ*(C8—H9), LP (O36) → σ*(C25—H28), LP (O43) → σ*(C16—H17) significantly influenced various topological analyses, including AIM, ELF, LOL, RDG, and IGM, producing favorable outcomes. [ABSTRACT FROM AUTHOR]

BaBiNb5O15- based oxide ion conductors have shown promise for solid fuel cell applications at medium temperatures. In this study, BaBi0.98Sr0.02Nb5-xTixO15-δ (x = 0.02, 0.04, 0.05, 0.06, 0.08) samples were prepared by the conventional solid-state synthesis with two-step sintering method. The electrical properties and oxygen relaxation behaviors of the BaBi0.98Sr0.02Nb5-xTixO15-δ samples were investigated. With increasing the Ti content, the bulk conductivity of the BaBi0.98Sr0.02Nb5-xTixO15-δ samples showed a trend of increasing first and then decreasing. When the doped Ti content reached 5 mol%, the highest bulk conductivity of BaBi0.98Sr0.02Nb5-xTixO15-δ samples can be got, 5.27 × 10−5 S/cm at 773 K. According to the dielectric relaxation spectroscopy measurement, the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ sample exhibits the higher moveable oxygen vacancy concentration and mobility of oxygen vacancies. This could be the possible reason that there is the highest bulk conductivity in the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ sample. Additionally, the influence of sintering temperature on the electrical properties of the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ compound was investigated. When the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ sample is sintered at a temperature of 1423 K, it exhibits the best bulk conductivity and total conductivity. [ABSTRACT FROM AUTHOR]

Cu/Nb laminated metallic composites (LMCs) exhibit extraordinary mechanical strength while electrical conductivity is maintained at a high level. In this research, Cu‐based LMCs with varying volume fraction of niobium are produced via accumulative roll bonding (ARB) and additionally cold‐rolled and heat‐treated to identify the role of these heterogeneous phase boundaries on the overall sheet properties. Deformation structures in these layered materials are studied through scanning transmission electron microscopy investigations. The existence of an interface‐affected zone at the phase boundaries and mechanical intermixing is attributed to decreasing electrical and increasing mechanical properties, especially in very thin layered LMCs. Atom probe tomography measurements show that mechanical alloying occurs due to severe plastic deformation during ARB processing of the laminates. An additional subsequent heat treatment leads to chemical demixing at the interfaces of the phase boundaries. [ABSTRACT FROM AUTHOR]

Achieving good compatibility between anodes and cathodes with electrolytes still faces great challenges in Mg metal batteries (MMBs). Recently developed amine‐based electrolytes have enabled reversible Mg anodes with conventional Mg salts through solvation structure regulations but still suffer from low conductivity and poor cathode compatibility. Herein, a Li/Mg double‐salt strategy is proposed to achieve the bulk phase‐interface‐electrode multi‐scale optimization for the amine‐based electrolyte, including ionic conductivity, anode stability, and cathode compatibility. Lithium triflate (LiOTf) serves as a multifunctional additive to compensate for the limitations of single Mg salt electrolyte (MgCl2/3‐methoxypropylamine). Li+ ions accelerate the ions transport in the bulk phase and ions insertion at the cathode side, benefitting to the conductivity and the cathode compatibility. Attributed to the high reduction stability of OTf− anions, the stable Mg anode/interface is also retained. Therefore, the Mg//SS cell achieves an ultralong cycling life for 2100 cycles with the coulombic efficiency of 99.8% at 1.0 mA cm−2 and the full cell also exhibits a superior cycling performance for 1000 cycles at 5 C. Additionally, the batteries with the optimized electrolyte are verified as a proof‐of‐concept for the air‐assembled MMBs. This work emphasizes the crucial role of multifunctional additives in enhancing amine‐based electrolyte performances. [ABSTRACT FROM AUTHOR]

Carbon nanotube fibers (CNTFs) are considered an ideal candidate as next‐generation conducting wires due to their high conductivity and low density. However, the orientation and compaction of the nanotubes in a CNTF need to be further improved to achieve even higher conductivity and ampacity. Here the fabrication of double‐wall CNTFs (DWCNTFs) is reported by a dry‐jet wet spinning method, which significantly improves the orientation and compaction of the carbon nanotubes (CNTs). As a result, the obtained DWCNTFs have a record high electrical conductivity of 1.1 × 107 S m−1 and ampacity of 8.0 × 108 A m−2. The fibers also have a high tensile strength of 1.65 GPa and a toughness of 130.9 MJ m−3, among the highest for wet‐spun CNTFs. The DWCNTFs preserve their integrity and conductivity after more than 5000 bending cycles. Theoretical calculations indicate that in a dry‐jet wet‐spinning process, gravity promotes the orientation of the CNTs along the axial direction of the fiber. [ABSTRACT FROM AUTHOR]

Flexible and stretchable ion‐conductive elastomers have shown promising applications in wearable flexible sensor devices, biopotential detection, electroluminescent devices, and other areas. However, the currently employed gel‐based ion‐conductive materials encounter issues such as solvent volatilization or leakage. Herein, there is an urgent requirement to develop a solid‐state ionic conductor material that is both safe and reliable, free from issues of liquid leakage. Here, the study reports a solid‐state ion‐conductive elastomer with excellent mechanical properties and high ionic conductivity based on a synergistic strategy of multiple interaction forces. The solid‐state ion−conductive elastomer exhibits high ionic conductivity (1.42 × 10−4 S cm−1 at 25 °C), superior stretchability (≈1550% elongation) and strength (1.48 MPa). Moreover, the solid‐state ion‐conductive elastomer exhibits high resilience and possesses excellent self‐healing ability. The wearable sensor, prepared based on the solid‐state ion‐conductive elastomer with excellent comprehensive performance, not only demonstrates high strain sensitivity but also captures high‐quality epidermal biopotential signals from the human body in biopotential detection. Additionally, the solid‐state ion‐conductive elastomer can serve as an electrode in ionic electroluminescent devices for human wearable applications. It is believed that the solid‐state ion‐conductive elastomer can provide novel opportunities for the advancement of wearable devices and soft ionotronics. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films have emerged as potential alternatives to indium–tin oxide as transparent electrodes in optoelectronic devices because of their superior transparency, flexibility, and chemical doping stability. However, pristine PEDOT:PSS films show low conductivities because the insulating PSS‐rich domains isolate the conductive PEDOT‐rich domains. In this study, the conductivities and corresponding spatially resolved Raman properties of PEDOT:PSS thin films treated with various concentrations of H2SO4 are presented. After the PEDOT:PSS films are treated with the H2SO4 solutions, their electrical conductivities are significantly improved from 0.5 (nontreated) to 4358 S cm−1 (100% v/v). Raman heat maps of the peak shifts and widths of the Cα═Cβ stretching mode are constructed. A blueshift and width decrease of the Cα═Cβ Raman mode in PEDOT are uniformly observed in the entire measurement area (20 × 20 µm2), indicating that microstructural transitions are successfully accomplished across the area from the coiled to linear conformation and high crystallinity upon H2SO4 treatment. Thus, it is proved that comprehensive Raman map analysis can be easily utilized to clarify microstructural properties distributed in large areas induced by various dopants. These results also offer valuable insights for evaluating and optimizing the performance of other conductive thin films. [ABSTRACT FROM AUTHOR]

The wettability of the proppant is crucial in optimizing the flowback of fracturing fluids and improving the recovery of the produced hydrocarbons. Neutral wet proppants have been proven to improve the fluid flow by reducing the interaction between the fluid and the proppant surface. In this study, a lightweight amphiphobic proppant (LWAP) was prepared by coating a lightweight ceramic proppant (LWCP) with phenolic resin, epoxy resin, polytetrafluoroethylene (PTFE), and trimethoxy(1H,1H,2H,2H-heptadecafluorodecyl)silane (TMHFS) using a layer-by-layer method. The results indicated that the LWAP exhibited a breakage ratio of 2% under 52 MPa (7.5 K) closure stress, with an apparent density of 2.12 g/cm3 and a bulk density of 1.21 g/cm3. The contact angles of water and olive oil were 125° and 104°, respectively, changing to 124° and 96° after displacement by water and diesel oil. A comparison showed that the LWAP could transport over a significantly longer distance than the LWCP, with the length increasing by more than 80%. Meanwhile, the LWAP displayed notable resistance to scale deposition on the proppant surface compared to the LWCP. Furthermore, the maintained conductivity of the LWAP was higher than that of the LWCP after displacement by water and oil phases alternately. The modified proppant could minimize production declines during hydrocarbon extraction in unconventional reservoirs. [ABSTRACT FROM AUTHOR]

We report the use of wet‐spinning to 3D‐print gels from low‐molecular‐weight gelators (LMWGs) based on the 1,3 : 2,4‐dibenzylidenesorbitol (DBS) scaffold. Gel stripes assembled from DBS‐CONHNH2 and DBS‐COOH are printed, and their conductivities assessed. Printed gels based on DBS‐CONHNH2 can be loaded with Au(III), which is reduced in situ to form embedded gold nanoparticles (AuNPs). The conductivity of these gels increases because of electron transport mediated by the AuNPs, whereas the conductivity of DBS‐COOH, which does not promote AuNP formation, remains lower. We then fabricate multi‐component gel patterns comprised of spatially well‐defined domains of printed DBS‐CONHNH2/AuNP (higher conductivity) and DBS‐COOH (lower conductivity) resulting in soft multi‐domain materials with differential conductivity. Such materials have future prospects in applications such as soft nanoelectronics or tissue engineering. [ABSTRACT FROM AUTHOR]

Urban and peri-urban lakes experience a wider array of environmental stressors, and often at a higher intensity, than their rural counterparts, including road salt runoff. A paleolimnological approach was used to determine pre-disturbance limnological conditions and to evaluate the impact of environmental stressors (nutrient inputs, climate change, and winter de-icing salt) on the long-term (~ 150 years) water quality of a small urban kettle lake in the Oak Ridges Moraine near Toronto, Ontario, Canada. Specifically, we examined Cladocera and diatom subfossils in 210Pb-dated sediment cores from a lake with elevated measured chloride concentrations, Haynes Lake (Cl− = 201 mg/l), and a nearby reference lake located in a conservation area (Swan Lake, Cl− = 28 mg/l). In Haynes Lake, Cladocera compositional change is consistent with increasing Cl− concentrations, showing a shift from a Bosmina spp.-dominated cladoceran assemblage to a Daphnia spp.-dominated assemblage. Concurrently, we recorded increases in the relative abundances of the diatom taxon Achnanthidium minutissimum and benthic fragilarioid taxa. These biological changes coincided closely with the onset of road salting in the region (ca. 1940s). The reference site (Swan Lake), located ~ 1 km from our salt-impacted site, displayed only minimal changes in both Cladocera and diatom assemblages, suggesting road development and salting within the Haynes Lake watershed had a larger impact than regional stressors (i.e., climate). [ABSTRACT FROM AUTHOR]

NASICON-structured Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 (LATP) solid electrolyte has low grain boundary conductivity, which impedes its practical application. Herein, W was adopted to partially replace the Al element in LATP to improve its grain boundary conductivity. The W doping reduces the crystal lattice of the electrolyte, which is detrimental to the grain conductivity. But the doping of W can make the grains closely connect and reduce the voids between the grains, which can greatly enhance the grain boundary conductivity. The LATP sample with the W doping content of 0.03 (LATWP003) exhibits the highest total ionic conductivity of 1.186 mS/cm at 30 ℃, which results from the optimum grain boundary conductivity of 2.315 mS/cm. Moreover, the LATWP003 electrolyte displays a negligible electronic conductivity of 2.01×10−9 S/cm. The LiFePO 4 /LATWP003/Li battery with PVDF-HFP polymer protective layer can be charged and discharged. Therefore, the W doped LATP sample is a promising electrolyte for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Y-doped BaZrO 3 is a well-researched material for proton-conducting fuel cells. One of the main limitations is the very high sintering temperature (∼ 1600 °C) necessary to densify the material. As Ba is lost at this temperature due to BaO evaporation, the stoichiometry is changed uncontrollably. This study is focused on evaluating the influence of slight changes in stoichiometry on microstructure, chemical stability, and conductivity of 20% Y-doped BaZrO 3 (BZY20) as well as 10% Y- and 10% Sc-co-doped BaZrO 3 (BZY10Sc10). Overall, Ba excess resulted denser microstructures with larger grains. Still, these samples were prone to decomposition by forming BaCO 3. Therefore, a slight Ba deficiency is favorable as the conductivity did not suffer in the examined stoichiometry region. [ABSTRACT FROM AUTHOR]

Herein, we offer a model for estimating the tunneling conductivity of polymer-graphene nanocomposites based on interfacial properties, the proportion of networked graphene, and the wettability value between the polymer medium and the filler. The interfacial properties are influenced by the minimum diameter of the nanosheets (Dc), whose conductivity can be transferred to the medium via interfacial conduction (τ). These parameters impact the actual aspect ratio and the volume proportion of the filler, which, in turn, control the onset of percolation and the proportion of nanosheets in the network. We apply all these parameters to develop a novel model for estimating the conductivity of graphene systems. The predictions obtained from this model across different parameter ranges are discussed. Additionally, experimental measurements are employed to evaluate the proposed equations. High filler conductivity enhances the nanocomposite's conductivity by a strong interfacial conduction. However, the conductivity cannot be transferred to the polymer medium under condition of weak interfacial conduction. Furthermore, a robust interphase and a small Dc contribute to increased conductivity. Ultimately, the developed equations accurately predict the onset of percolation and conductivity, validated by real experimental data. [ABSTRACT FROM AUTHOR]

In this work, Co0.5Zn0.5LaxFe2-xO4 (0.00 ≤ x ≤ 0.10) spinel ferrites were synthesized using the sol-gel auto-combustion method. X-ray diffraction (XRD) analysis and Rietveld refinement confirmed the presence of a cubic spinel structure. The crystallite size was estimated to be between 17.5 nm and 26.5 nm using Scherrer's method and 31.27 nm-54.52 nm using the Williamson-Hall (W-H) method. Lattice constants determined from XRD and Rietveld refinement ranged from (8.440 to 8.433 Å and 8.442 to 8.431 Å), respectively. Scanning electron microscopy (SEM) revealed a non-uniform distribution of morphology with a decrease in particle size. The bandgap values decreased from 2.0 eV to 1.68 eV with increasing rare earth (La3+) doping concentration. Fourier-transform infrared (FT-IR) spectroscopy confirmed the presence of functional groups and M-O vibrations. The dielectric constant and dielectric loss exhibited similar behavior across all samples. The maximum tan d value obtained at lower frequencies. Regarding magnetic behavior, there was a decrease in magnetization from 55.84 emu/g to 22.08 emu/g and an increase in coercivity from 25.63 Oe to 33.88 Oe with higher doping concentrations. Based on these results, these materials exhibit promising properties for applications in microwave and energy storage devices. [ABSTRACT FROM AUTHOR]

The conductivity for half-filled disordered Hubbard model in different interaction regimes is studied using a typical medium dynamical mean-field theory. The Kubo formula with the geometrically averaged Green function is used to calculate the optical and dc conductivity of the system. The dependence of the conductivities in the model on the random potential and temperature in the weak and intermediate interaction regimes is investigated numerically. It is shown that in the weak interaction regime at a fixed temperature the optical conductivity at low frequencies as well as the dc conductivity get decreased as disorder strength increases. Whereas in the intermediate interaction regime, the results show a reentrant effect of the insulating phases. Our dc conductivity of a non-interacting disordered system is consistent with those known in the literature and our other results are in agreement with the phase diagram obtained by using typical medium theory with different impurity solvers. [ABSTRACT FROM AUTHOR]

In organic solar cells (OSCs), the electron transport layer (ETL) is vital for high performance devices. As a widely used ETL, N-oxide-functionalized perylene-diimide (PDINO) is often limited by its low conductivity. Herein, we develop an improved ETL by doping indole carbonized polymer dots (CPDs) into PDINO. The graphitic N and oxoindole groups of CPDs could increase the self-doping of PDINO. Compared with the pristine PDINO ETL, the PDINO + CPDs ETL shows a more suitable work function and higher conductivity due to the graphitic nature of CPDs and the enhanced self-doping of PDINO. PM6:Y6 OSCs with a 10 nm PDINO + CPDs ETL demonstrate a superior average power conversion efficiency (PCE) (17.0%) compared with OSCs with only a PDINO ETL (15.6%). This improvement in PCE is attributed to the enhanced efficiency of exciton dissociation and reduced charge recombination within the devices. Furthermore, OSCs utilizing PDINO + CPDs ETL display a notable resilience to variations in ETL thickness, maintaining a high average PCE of 15.0% even when the ETL thickness is increased to 70 nm. This work provides a simple interfacial modification strategy to optimize ETLs for OSCs. [ABSTRACT FROM AUTHOR]

Copper(I) thiocyanate (CuSCN) is a prominent wide‐bandgap p‐type semiconductor with desirable transparency and chemical robustness. Whereas intrinsic limitations, such as its relatively low Fermi level (EF) and modest electrical conductivity, have impeded its broader application in organic solar cells (OSCs). This study introduces a novel approach to modify the electronic properties of CuSCN by inducing copper vacancies through the use of specific solvent mixtures, thereby enhancing its suitability for OSCs. The effects of two solvent mixtures, methanol/ammonia (CH3OH/NH4OH) and dimethyl sulfoxide/N,N‐Dimethylformamide (DMSO/DMF) is have systematically investigated, on the CuSCN layer. The findings reveal that these solvent systems induce a higher concentration of copper vacancies within the CuSCN film, resulting in a significant reduction of the EF and a substantial increase in electrical conductivity. These modifications have led to the improved energy level alignment with the PM6:L8‐BO:BTP‐eC9 blended photoactive layers, culminating in a marked enhancement of the power‐conversion efficiencies of 19.10% for the DMSO/DMF processed CuSCN layer. Additionally, it has observed enhanced shelf/thermal stability and thickness tolerance of OSCs based on these CuSCN films. This work not only presents a novel strategy for modifying the performance characteristics of CuSCN but also underscores its potential to contribute to the advancement of photovoltaic technologies. [ABSTRACT FROM AUTHOR]

The crystal structure, oxygen content and homogeneity range of Pr 1-x Sr x CoO 3-õ solid solutions from room temperature (RT) up to 1100 °C in air were studied. It has been shown that an increase in temperature and Sr content causes an Orthorhombic → Rhombohedral → Cubic transformation of the crystal structure. The heterovalent substitution of Sr2+ for Pr3+ is compensated by an increase in the mean oxidation state of Co ions (z Co) and the formation of oxygen vacancies. The temperature dependences of thermal expansion and conductivity of Pr 1-x Sr x CoO 3-õ solid solutions are explained from the point of view of crystal and defect structure. The diagram of phase relation in the PrCoO 3 – "SrCoO z " cross section has been constructed. [ABSTRACT FROM AUTHOR]

This study extensively investigates Ni 0.4 Cu 0.2 Zn 0.4 Fe 2-4x Sn 3x O 4 (x ≤ 0.10) nanospinel ferrites, denoted as NCZFe 2-4x Sn 3x O 4 NSFs, focusing on their structural, morphological, electrical, and dielectric characteristics. Utilizing various techniques such as SEM, EDX, TEM, XRD, and impedance analysis, the research confirms the cubic spinel structure and composition of the nanoferrites. The substitution of Sn 4+ ions into Ni 0.4 Cu 0.2 Zn 0.4 Fe 2 O 4 NSFs is explored, with a thorough examination of dielectric and electrical parameters up to 1.0 MHz and temperatures ranging from 20 to 180 °C. Complex impedance spectroscopy is employed to represent these parameters in a logarithmic 3D graph, revealing insights into ac/dc conductivity, activation energies, dissipation factor, dielectric constant, and loss. The study observes adherence to the power-law frequency rule in ac conductivity and highlights the impact of temperature and substitution ratios on grains, grain boundaries, and elemental composition. The investigation suggests a conduction mechanism involving electron and polaron hopping , and ionic contributions. Dielectric parameters show frequency-dependent changes that relate the dielectric constant to space charge polarization, inhomogeneous dielectric structure, impurities, and grains /grain boundaries. Cole-Cole impedance plots display semicircles dependent on substitution ratios and temperature, emphasizing contributions from grains, grain boundaries, and ionic mobilities. The Nyquist plots of Cole-Cole impedance functions further underscore substantial complexity in the conduction mechanism of the substituted NCZFe 2-4x Sn 3x O 4 NSFs. [ABSTRACT FROM AUTHOR]

High electrochemical and durability anion exchange membranes (AEMs) are a vital material for Flexible zinc‐air batteries (F‐ZAB) and AEM water electrolysis (AEMWE) to achieve green economy and environmental protection. However, the existing AEMs possess the disadvantages of a complicated preparation process, poor homogeneity, and unsatisfactory electrochemical performance. Here, a novel alkaline exchange membrane is synthesized using bacterial cellulose (BC) as the matrix, incorporating constrained in situ Poly (diallyldimethylammonium chloride) (PDDA) polymerization and double chemical cross‐linking techniques. By adjusting the microstructure, a unique long‐range order and dense internal structure to address the issue of loose bonding between PDDA and BC is established and achieve the purpose of rapid OH− conduction. The membranes exhibit excellent application properties, with excellent ionic conductivity (145.12 mS cm−1) and superb mechanical strength (73.26 MPa). Consequently, the membrane is assembled into the F‐ZAB, and the unprecedented power density of 258.7 mW cm−2 can be achieved at room temperature. Moreover, the membrane also can reach 3.0 A cm−2 at 2.3 V, indicating good prospects in the field of water electrolysis in 6 m KOH. The approach paves a new path for manufacturing AEMs for green energy and environmental applications. [ABSTRACT FROM AUTHOR]