DC Conductivity Measurements Research Articles

Enhanced optical, dielectric and transport properties in PVDF based (La0.5Bi0.5FeO3)0.5-(BaTiO3)0.5 composites

In this comprehensive study, we investigated PVDF composites incorporating LaBiFeO3-BaTiO3 (LaBiFO-BaTO) perovskite fillers, focusing on their structural, optical, dielectric, impedance, modulus and DC-conductivity properties. The fabrication involved precise preparation of LaBiFO-BaTO perovskite via solid-state reaction, ensuring phase purity conducive to composite integration. Using a solution casting method, PVDF films with varying LaBiFO-BaTO concentrations (5 %, 10 %, and 15 % wt) were successfully synthesized. XRD confirmed the synthesis of single-phase LaBiFO-BaTO and revealed structural modifications in PVDF composites, highlighting improved filler-matrix interactions at higher concentrations. Scanning electron microscopy and atomic force microscopy depicted the morphological evolution and surface roughness changes with increasing filler content. Optical studies indicated a red shift in absorption spectra with higher LaBiFO-BaTO concentrations, correlating with a decrease in the direct band gap energy of the composites. Electrical characterization demonstrated enhanced dielectric properties and impedance behaviour in PVDF/LaBiFO-BaTO composites, suggesting their suitability for applications in capacitors and optoelectronic devices. This systematic investigation provides valuable insights into optimizing PVDF-based composites for advanced functional materials. The composites exhibit enhanced dielectric permittivity at room temperature, attributed to space charge polarization and the high dielectric constant of LaBiFO-BaTO. Dielectric loss (tanδ) remains minimal (<0.1), decreasing with frequency, indicative of low energy dissipation suitable for high-frequency applications. Further the dielectric relaxation have been examined using Havrilak-Negami model. Impedance and modulus analyses reveal temperature-dependent behaviours, with reduced impedance and enhanced charge transfer kinetics in higher concentration composites. DC conductivity measurements demonstrate increased charge transport properties with temperature, influenced by thermally activated charge hopping mechanisms. Overall, PVDF/LaBiFO-BaTO composites show promising characteristics for capacitors, sensors, and optoelectronic devices, suggesting avenues for further optimization and broader application in advanced technologies.

Ultrahigh-mobility microbial cytochrome nanowires generate power from humidity.

Mixed electronic-ionic conductors are crucial for various technologies, including harvesting power from humidity in a durable, self-sustainable, manner unrestricted by location or environment1,2. Biological proteins have been proposed as mixed conductors for 50 years3,4. Recently, Geobacter sulfurreducens pili filaments have been claimed to act as nanowires to generate power5,6. Here, we show that the power is generated by G. sulfurreducens-produced cytochrome OmcZ nanowires that show 20,000-fold higher electron conductivity than pili7. Remarkably, nanowires show ultrahigh electron and proton mobility (>0.25 cm2/Vs), owing to directional charge migration through seamlessly-stacked hemes and a charged, hydrogen-bonding surface, respectively. AC impedance spectroscopy and DC conductivity measurements using four-probe van der Pauw and back-gated field-effect-transistor devices reveal that humidity increases carrier mobility by 30,000-fold. Cooling halves the activation energy, thereby accelerating charge transport. Electrochemical measurements identify the voltage and mobilities required to switch pure electronic conduction to mixed conduction for power generation. The high aspect ratio (1:1000) and hydrophilic nanowire surface captures moisture efficiently to reduce oxygen reversibly, generating large potentials (>0.5 V) necessary to sustain high power. Our studies establish a new class of biologically-synthesized, low-cost and high-performance mixed-conductors and identify key design principles for improving power output using highly-tunable electronic and protein structures.

Investigation on structural, optical, thermal, and dielectric properties of nanocomposite films based on chitosan containing vanadium pentoxide/zinc oxide and their potential for optoelectronics devices

Chitosan (Cs), zinc oxide (ZnO), and vanadium pentoxide (V2O5) nanoparticles (NPs) have been used to create ternary nanocomposite materials to improve their optical and electrical characterization. Physical methods have been used to investigate the effects of varying vanadium pentoxide nanoparticle contents on the optical and electrical characterization of the prepared films. In XRD results obtained, the characteristic peaks of pure chitosan are seen to be broken and vanished (especially at 15 wt.% V2O5 NPs). This means that when chitosan is filled with different concentrations of V2O5 nanoparticles, chitosan is very weak and simply broken, and only characteristic peaks of V2O5 appear. The average crystal size of V2O5 has been determined to be 25.4 nm. FTIR spectra approve the strong complexation between the nanoparticles and hydrogen bonds in the composite. The study suggests that the addition of zinc and vanadium nanoparticles to chitosan-based films can improve their thermal stability, which has potential applications in various industries, including packaging, biomedical, and environmental. Electrical studies indicate that as the content of embedded zinc/vanadium-filled-in chitosan rises, the ε′ value decreases. The observed decrease in the insulating behavior of chitosan aligns with the notion that doping reduces its insulating properties. This aligns with the enhanced electrical conductivity evident from the DC conductivity measurements. The study demonstrates that incorporating zinc oxide (ZnO) and vanadium pentoxide nanoparticles effectively influences the dielectric properties and relaxation behavior of chitosan. The given results suggest Ternary nano-composite chitosan-ZnO/V2O5 films for specific requirements in optical, optoelectronic applications.

Modification of thermal and electrical characteristics of hybrid polymer nanocomposites through gamma irradiation for advanced applications

In this article, we present a straightforward in-situ approach for producing Ag NPs incorporated in graphene oxide (GO) blended with glutaraldehyde (GA) cross-linked polyvinyl alcohol (PVA) matrix. Samples are γ-irradiated by doses of 2, 5, and 10 kGy and in comparison with the pristine films, the thermal conductivity (‘k’) and effusivity are measured. ‘k’ decreases with irradiation doses up to 5 kGy and further increase in the dosage results increase in ‘k’. We performed FDTD modeling to verify the effect of polarization and periodicity on the absorptivity and emissivity spectra that are correlated to the ‘k’ and effusivity, empirically. Hence, we can confess that the structural properties of the prepared hybrid nanocomposite are manipulated by γ-irradiation. This attests that the PVA/GO-Ag/GA nanocomposite is radiation-sensitive and could be employed for thermal management systems. Moreover, their strong electrical insulation, as the measured dc conductivity of the γ-irradiated samples is found to be in the range of 2.66 × 10−8–4.319 × 10−7 Sm−1, which is below the percolation threshold of 1.0 × 10−6 Sm−1, demonstrates that they are excellent candidates for the use of thermal management materials. The low ‘k’ values allow us to use this promising material as thermal insulating substrates in microsensors and microsystems. They are also great choices for usage as wire and cable insulation in nuclear reactors due to their superior electrical insulation.Graphical

High specific capacitance and NTC behavior of substituted cobalt oxide spinels for electrochemical supercapacitor and thermistor applications

Due to the growing importance of low-cost energy storage devices in smart device applications, finding an appropriate electrode material with the least self-discharging, high power, and energy densities is the need of the hour. In this paper, Cu and Mn-modified Co3O4 spinels in the form of CuCo2O4 and MnCo2O4 are reported as the most promising electrode materials for high-performance electrochemical supercapacitors. Modified Co3O4 spinels were prepared by the co-precipitation technique, and the X-ray diffraction (XRD) studies show a single-phase formation with cubic crystal symmetry. The average crystallite size estimated by considering the highest intensity peak of the diffraction pattern using Scherrer’s relation shows the average crystallite size below 30 nm for reported spinels. Scanning electron microscopic (SEM) images stabilize the fact that grains with nanosizes consisting of regular shapes and excellent morphological features. The dc-conductivity measurement establishes the essence of negative temperature coefficient of resistance (NTCR) behavior in nanostructured spinels. The specific capacitance (Cs) of CuCo2O4 and MnCo2O4 estimated using cyclic voltammetry (CV) was found to be 616.074 F g−1 and 1401.16 F g−1 for a scan rate of 10 mV s−1 with verified stability up to 1000 cycles. The low internal resistance value in the range of 0.1 Ω for both the spinels verified by the electrochemical impedance spectroscopy (EIS) graph confirms these spinels as encouraging electrode materials for electrochemical supercapacitors.

Compaction pressure effect on the dielectric, DC and AC conductivity of C-130 porcelain

Porcelain insulators can be prepared in a variety of compositions using several different preparation techniques. In the frame of the present work the effect of the applied compaction pressures on the C-130 grade electroporcelain was studied in terms of electrical and dielectric properties. Compaction is a widely used preparation process, nevertheless, a little is known about the effect of the compaction pressure on the final electrical properties of the material. Samples prepared with different compaction pressures (from 70 MPa to 110 MPa; 10 MPa step size) were subjected to a measurement of DC conductivity up to 1200 °C, and a measurement of dielectric properties at room temperature after different firing temperatures. The DC conductivity of the raw samples ranged from ∼10−10 S/m at room temperature to <10−3 S/m at 1100 °C. Temperature dependence of the DC conductivity revealed that the dominant charge carriers were H+ and OH− ions (initial stages of heating) and alkali ions (at high temperatures and during second heating). The DC conductivity of the previously fired samples (at 1100 °C) ranged from ∼10−12 S/m (room temperature) to ∼10−3 S/m (1200 °C). The AC conductivity of the samples ranged from ∼10−7 S/m (samples fired at 1300 °C, measured at low frequencies) to ∼10−3 (raw sample, measured at high frequencies). AC conductivity measurements and dielectric analysis confirmed that the conduction occurred through ion hopping and the bulk boundary conductivity was dominant. The relative permittivity reached 7–8 after firing at 1300 °C at frequencies above 2 MHz.

Enhanced electrical conductivity and charge conduction mechanisms in Nano-cubical Sunset Yellow dye incorporated with titanium dioxide nanoparticles

This manuscript focuses on the investigation of the effect of titanium dioxide nanoparticles doping on the electrical conductivity of Nano-cubical Sunset Yellow Dye. The successful preparation of the composite was confirmed through XRD analysis, and EDX analysis verified the composite's composition. DC conductivity measurements revealed two conduction mechanisms with activation energies of 0.683 eV and 0.466 eV for the dye without NPs at low and high-temperature regions, respectively, and 0.532 eV and 0.351 eV for the same regions in the presence of NPs. AC conductivity analysis showed single polaron hopping as the dominant charge conduction mechanism for both devices. The device with the dye-NP composite exhibited lower activation energy and improved conductivity compared to the dye-only device. The composite also displayed a higher density of localized states, and by incorporation of NPs reduced the hopping length, contributing to the enhanced conductivity of the composite device.

Effect of ambient argon pressure on the structural, optical and electrical properties of non-crystalline Se85Te3Bi12 nano-thin films

In this research work, we have synthesized non-crystalline Se85Te3Bi12 chalcogenide glasses by conventional melt quenching technique. The differential scanning calorimetry measurement of the synthesized specimen was done to confirm the glassy as well as non-crystalline nature of the bulk Se85Te3Bi12 alloy. The nano-thin films of thickness 30 nm of the synthesized sample at two different ambient argon pressures (1 Torr and 3 Torr) were made using the physical vapor condensation technique at a constant substrate temperature of 77 K using liquid nitrogen. The non-appearance of prominent peaks in the high-resolution x-ray diffractometer profile confirmed the non-crystalline nature of synthesized nano-thin films. The morphological analysis of the prepared nano-thin films using Field emission scanning electron microscopy confirmed the nanochalcogenide having particle size ranges from 30–90 nm. The Fourier transform infrared (FTIR) spectroscopy suggests the presence of moisture and carbon impurities in the prepared nano-thin films. The broad optical transmission shadow observed in the FTIR results is an essential requirement for new-generation IR systems. Based on UV-visible spectroscopy, optical parameters such as optical absorption coefficients, Urbach energy, optical band gaps, Tauc’s parameter and extinction coefficients were measured for synthesized Se85Te3Bi12 nano-thin films. The value of absorption coefficients, Tauc’s parameters, optical band gap and extinction coefficients increases with the increase of ambient argon pressure. The outcome of these studies recommends that these materials can be a preeminent candidate for photovoltaic applications. Photoluminescence spectroscopy results are accredited to the accumulation of non-crystalline nanochalcogenide particles on the substrates. DC conductivity measurements further confirm the semiconducting nature of the nanochalcogenide Se85Te3Bi12 thin films.

Structural, electrical and dielectric properties of ZnFe2O4/Cu2S 3D heterostructures

This work reports the fabrication of zinc ferrite-copper sulphide (ZnFe2O4/Cu2S) 3D heterostructures and subsequent investigation of the spectroscopic behaviour of various electrical parameters like conductivity, impedance and dielectric loss. The study reveals a non-monotonic behaviour of the real component of impedance (Z’), while the imaginary component of impedance (Z’) exhibits a temperature-dependent relaxation frequency, with an estimated activation energy (E a ) of 220.13 meV. The dc conductivity (σ dc ) measurements reveal the semiconducting nature of the sample and a transition from a ferrimagnetic to a paramagnetic behaviour is reported at the Curie temperature of 327 K. In case of ac conductivity (σ ac ), Jonscher’s power law σ ac = Aω n is followed and the exponent n is found to lie in the range 0.679–0.735 at different temperatures, which is best fitted into a polynomial of degree six. The temperature variation of n is suggestive of the overlapping large polaron tunnelling (OLPT) model. Further, ac activation energy (E ac ) is also calculated, which is found to be smaller than the dc activation energy (E dc ), indicating electron hopping between Fe3+ and Fe2+ ions. The numerically computed staying time (τ) of electrons in Fe3+/Fe2+ ionic sites varies with frequency as well as with temperature, ranging from 10−6s to 10−19s. A significant decrease in dielectric loss (tanδ) to the tune of 99% (from 75 at ∼100 Hz to 0.89 at ∼1 MHz) is reported at room temperature. In the present scenario, when smart materials like spinel ferrites have garnered significant attention for their promising magnetic and electric properties, our studies of the ZnFe2O4/Cu2S 3D heterostructures may provide immense possibilities for tailored applications in various electromagnetic applications.

The novel oxy-sulfide glassy ionic conductors Na4P2S7-xOx 0 ≤ x ≤ 7: Understanding the features of static and dynamic cations

We present a 23Na nuclear spin dynamics model for interpreting nuclear magnetic resonance (NMR) spin-lattice relaxation and central linewidth data in the invert glass system Na4P2S7-xOx, 0 ≤ x ≤ 7. The glassy nature of this material results in variations in local Na+ cation environments that may be described by a Gaussian distribution of activation energies. A consistent difference between the mean activation energies determined by NMR and DC conductivity measurements was observed, and interpreted using a percolation theory model. From this, the NaNa coordination number in the sodium cation sublattice was obtained. These values were consistent with jumps through tetrahedral faces of the sodium cages for the sulfur rich glasses, x < 5, consistent with proposed models of their short range order (SRO) structures. From NMR spin-echo measurements, we determined the NaNa second moment M2 resulting from the NaNa magnetic dipole interaction of nearest neighbors. Values of M2 obtained as a function of sodium number density N were in agreement with models for uniform sodium distribution, indicating that these invert glass systems form so as to maximize the average NaNa distance. A simple Coulombic attraction model between Na+ cation and X (=S−, O−) anion was applied to calculate the activation energy. In the range 1.5 ≤ x ≤ 7, an increase in activation energy with increasing oxygen content x occurred, and was consistent with the decrease in average anionic radius, and the increase in Coulombic attraction. For small oxygen additions, 0 ≤ x ≤ 1.5, the suggested minimum at low oxygen concentration seen in the activation energies obtained from DC conductivity data is not evident in the model.

Enhancement in Li-ion conductivity through Co-doping of Ge and Ta in garnet Li7La3Zr2O12 solid electrolyte

For use as an electrolyte in All Solid State Batteries (ASSB), a solid electrolyte must possess ionic conductivity comparable to that of conventional liquid electrolytes. To achieve this conductivity range, the series Li6.8-yGe0.05La3Zr2-yTayO12 (y = 0, 0.15, 0.25, 0.35, 0.45) has been synthesized using a solid-state reaction method and studied using various characterization techniques. The highly conducting cubic phase is confirmed from XRD analysis. Structural information was collected using SEM and density measurements. The prepared ceramic sample containing 0.25 Ta, sintered at 1050 °C for 7.30 hrs, shows the maximum ionic conductivity of 6.61 x 10-4 S/cm at 25 °C. The air stability of the same ceramic has also been evaluated after exposure for 5 months. The minimum activation energy associated with the maximum conductivity of 0.25 Ta is 0.25 eV. The DC conductivity measurements were done to confirm the ionic nature of conductivity for all ceramic samples. The stable result of ionic conductivity makes the 0.25 Ta containing ceramic sample a promising candidate for solid electrolytes for ASSB applications.

Smart Refractory Sensors Development for Corrosion and Erosion Monitoring in High Temperature Systems

To optimize the operation and functioning of high temperature systems such as slagging gasifiers, coal boilers and glass/steel melters, it is important to monitor corrosion and erosion of refractory used in such systems. Corrosion test strategies are generally based on continuous gravimetric and chemical reactivity monitoring at operational temperatures (750°-1500°C). Both thermocouples and failure sensors and arrays would be useful to monitor the health of any refractory or coatings in these systems. Many of such type of sensors are installed into the systems through open access ports within the refractory; however, there are some disadvantages of this approach where corrosive/erosive gas and molten materials can penetrate and compromise the system. The current work presents the development and performance demonstration of smart refractory with embedded high temperature sensors such as thermocouples, thermistors, and various spallation/crack monitoring sensors, which may be used within a variety of refractory brick in different high temperature processes and applications.The main feature of this technology is that electroceramic based sensors are embedded into smart refractory without significantly impact to the intrinsic properties of the refractory. This technology circumvents the need to insert an isolated monolithic, stand-alone sensor into the refractory via an access port. This technological approach guarantees the integrity and the chemical stability of the materials used in the sensor fabrication within the harsh environment and does not introduce molten material (such as slag) penetration pathways within the refractory. One interesting and important aspect of this innovation is that these embedded sensors can be used to in situ monitoring processes such as chemical reactions and at the same time give information and a deeper understanding of the corrosion and erosion process of the refractory within the system.As stated above, the objective of our work is to develop high-temperature sensors composed of electroceramic materials that are chemically stable at high temperatures (750°-1500°C) and high pressures (up to 1000 psi) that can be used in monitoring corrosion and erosion process in refractory used in high energy systems. The high-temperature sensors investigated in this work were composed of various oxide composites directly embedded into the refractory oxides. The composites used for this work were synthesized by a mixed-oxide route. Metal oxides were inserted within a matrix material composed of refractory oxides (Al2O3, ZrO2, etc.). The physical and electrical properties were specifically manipulated by altering the level of percolation of the conductive species (metal oxides) within the refractory constituent (refractory oxide).Prior to the development of the high-temperature sensors, the oxides composites developed in this study were sintered up to 1600°C under oxidizing atmosphere in order to investigate densification, microstructural evolution, phase development, and their thermoelectrical performance as a function of the composition. The 4-point DC conductivity measurements were performed between 100°-1500°C. The sensors were fabricated from the composite materials by 3D-printing or screen-printing methods into the refractory brick during the consolidation process.An example of one of these embedded sensors consisted of an electroceramic-based thermocouple fabricated with two separate oxide composite compositions which were patterned to produce a couple within the interior of a refractory matrix. The thermocouple successfully displayed thermoelectric voltage trend (as a function of temperature), and the voltage was 220.0 mV around 1400 °C.Corrosion tests on the refractory embedded sensors were performed. To evaluate corrosion in the refractory brick an in-house glass composition was prepared and pressed into pellets and delivered into a pre-cut cavity in the brick. Corrosion experiments results showed the glass penetrated the brick over a 90 h period, and the penetration of the glass through the brick could be monitored by both a amperometric and voltametric based sensor. With this experiment, it was demonstrated that the embedded sensor could dynamically monitor the corrosion process. Acknowledgements: This work was supported by the United States Department of Energy (DOE) through the research project grant (DE-FE0031825). The authors would also like to acknowledge the technical support of Dr. Qiang Wang, Dr. Marcela Redigolo and Mr. Harley Hart of WVU Shared Research Facilities (SRF) for assistance in characterization and technical input.

Oxygen exchange and transport properties of the first-order Ruddlesden-Popper phase La2Ni0.9Co0.1O4+δ

The rare earth nickelate La2Ni0.9Co0.1O4+δ (LNCO) was synthesized via the citrate/EDTA method. X-ray powder diffraction confirmed that the material is single-phase and crystallizes in the orthorhombic K2NiF4-type structure. In-situ dc-conductivity and conductivity relaxation measurements on a bar-shaped sample were applied to determine the electronic conductivity as well as the chemical surface exchange coefficient and chemical diffusion coefficient of oxygen from 600 °C to 850 °C and 0.01 ≤ pO2 / bar ≤ 0.1. The results indicate that substitution of nickel with cobalt in La2Ni0.9Co0.1O4+δ leads to significantly higher values of the surface exchange coefficient compared to La2NiO4+δ, while the electronic conductivity is somewhat reduced. The oxygen non-stoichiometry of LNCO was studied by thermogravimetry in the same temperature and oxygen partial pressure range. The measured thermal expansion coefficients of LNCO fit well with those of common solid electrolytes such as GDC and YSZ. Self-diffusion coefficients of oxygen and ionic conductivities were calculated from the experimentally determined diffusivities and the thermodynamic factor of oxygen by using the Nernst-Einstein relation. The results indicate that LNCO offers an attractive option for application as air electrode in solid oxide cells.

Green energy production by NiFe2O4 based hydroelectric cells

Hydroelectric cell is a great invention that uses only a few drops of water to generate green energy. This cell produces green power by dissociating of water molecule at room temperature into hydroxide and hydronium ions. Nickel ferrite samples support the dissociation of water molecules via chemidissociation and Phys-dissociation. NiFe2O4 sample was synthesized by solid-state sintering method for hydroelectric cell. Structural information of the sample was investigated by XRD and FTIR analysis. Hydroelectric properties were examined by preparing circular pellets having dimension of 2-inch diameter. At the same time, the conduction phenomenon of the split ions was studied by preparing 10 mm diameter circular pellet. The synthesized nickel ferrite hydroelectric cell achieved a maximum voltage of 0.926 V, peak current of 6.98 mA and peak power of 6.46 mW. The conduction phenomenon of dissociated water molecules was examined using dielectric and DC conductivity measurements.

Positron annihilation studies of methylammonium lead bromide perovskite

Methylammonium lead halide-based perovskite has shown excellent optoelectronic properties. But their performances and stability are critically affected by the ionic defects present in the crystal lattice. In this article, we have investigated the presence of ionic vacancy mediated defects formation in ball mill ground methylammonium lead bromide (MAPbBr3) which has applications in tandem solar cell, light emitting diodes and laser devices. The evaluation of those point defects with temperature was analysed by employing the positron annihilation spectroscopic (PAS) studies. The phase transition from tetragonal to cubic phases around 260 K was exactly correlated with the temperature-dependent ‘S parameter’ determination from PAS analysis and with dc conductivity measurement. From coincidence Doppler broadening (CDB) spectroscopy significant proportion of defects arising from lead vacancy was observed whose magnitude reduces from the low-temperature tetragonal phase to higher temperature cubic phases.

"Preparation of SnO2 thin films by doping with F-1 ions using chemical spray pyrolysis"

In this paper, the structural and optical properties of pure Tin Oxide and doped by Fluorine (F). Thin films were studied prepared by chemical spray pyrolysis on glass substrates at temperature 400oC. The nature of crystallization of the compounds was examined by using X-Ray diffraction technique which showed that the prepared thin films are polycrystalline structure, and the doping processes didn,t show any obvious differences on the crystalline structure of (SnO2). The DC conductivity measurements of the samples were performed by means of a two probe method. The activation energies were computed from the plots of σdc versus 1000/T. To obtain the optical parameters, the absorption and transmittance spectra were recorded in the wave length range 300-1100 nm, the energy gap of the direct and indirect allowed transition were calculated. The optical parameters such as absorption coefficient (α), refractive index (n), extinction coefficient (Ko), dielectric constant (ε'), and dielectric loss (tanδ), were also investigated.

Effect of K+ cation doping on structural and morphology of MgFe2O4 and their role in green electrical energy generation

Recent development in generation of green electrical energy using porous oxide is a promise of economic and sustainable energy source. Pure and K-doped MgFe2O4 based hydroelectric cells with mesoporous structure and good chemical stability were synthesised by solid-state sintering method. Energy production with zero carbon emission can be achieved by dissociation of water molecules with this novel device named as Hydroelectric cell. Rietveld analysis of powder X-Ray data was performed to investigate the structural and phase analysis of prepared samples. FESEM was used to depict the surface morphology of all the samples. Water molecules dissociation and ionic conduction of dissociated ions were further investigated by dielectric and dc conductivity measurements for all the samples in dry and wet states. Load analysis of cell was performed to understand its practical applications. Maximum out power was observed for Mg0.9K0.1Fe2O4 based Hydroelectric cell. Overall results conclude that K+ cation doping induce nano porous structure in MgFe2O4 results in better hydroelectric properties which may use as nonconvention source of energy.

Study of structural, electrical, and magnetic properties of Co-Zn ferrite and Co-Zn ferrite/polythiophene nanocomposite

In the present work, a comparative study of structural, electrical, and magnetic properties of Co-Zn ferrite and Co-Zn ferrite/Polythiophene (PTh) nanocomposite has been done. The Co-Zn ferrite was synthesized by the sol–gel auto-combustion method and Co-Zn ferrite/PTh nanocomposite through in-situ polymerization. The PXRD analysis confirmed the spinel cubic phase of ferrite nanoparticles. FTIR spectra showed the vibrations corresponding to both ferrite and polythiophene. The morphology of the nanocomposite showed ferrite nanoparticles are well dispersed in the polymer, inferring the core–shell structure of the nanocomposite. The encapsulation of ferrite nanoparticles by the polymer, however, decreased the saturation magnetization of the sample. The squareness ratio (M r /M s ) was found to be 0.345 for Co-Zn ferrite, and 0.380 for Co-Zn ferrite/PTh nanocomposite. DC conductivity measurements showed a higher value for nanocomposite than ferrite nanoparticles. The Co-Zn ferrite/PTh nanocomposites could be an efficient material for electromagnetic interference shielding applications.

Alkali (Na, K) doped SnO2: An investigation on the role of microstructure on electricity generation of oxide based ceramic hydroelectric cells

Generation of green electricity using porous nanostructure is a novel idea towards sustainable unconventional source of energy. Inexpensive, portable, eco-friendly, and biodegradable Alkali (Na, K) doped tin oxide nano porous structured hydroelectric cells were prepared by solid-state technique. X-Ray diffraction and Fourier transform infrared spectroscopy analysis have been performed to confirm the phase formation of the samples. Field emission scanning electron microscopy was used to investigate surface morphology of all the samples. Mesoporosity of the samples was confirmed by Barrett‐Joyner‐Halenda technique. Two-inch diameter circular pellets were prepared to investigate hydroelectric properties and it was found that maximum output power of 61.5 mW delivered by 5 Mol% K doped SnO2 HEC. The observed electricity generation in doped SnO2 samples is more sustainable as compared to pure SnO2 HEC. Water molecules dissociation and ionic conduction of dissociated ions were further investigated by dielectric, dc conductivity measurements for all the samples in dry and wet states. Observed results show that Alkali element doped tin oxide nano porous structured hydroelectric cells may use as nonconvention source of energy.

Rational Construction of Molecular Electron-Conducting Nanowires Encapsulated in a Proton-Conducting Matrix in a Charge Transfer Salt.

Insulated molecular wires have gained significant attention owing to their potential contribution in the fields of nanoelectronics and low-dimensional chemistry/physics. Based on molecular charge transfer salts, we demonstrate, for the first time, the rational construction of molecular electron-conducting wires encapsulated in a proton-conducting matrix, which possibly paves the way to ionoelectronics. As expected from the molecular structure of the newly designed complex anion (i.e., propeller-shaped structure with hydrogen-bonding sites at four edges), a three-dimensional hydrogen-bonded framework was constructed within the crystal, which contains a one-dimensional array of an electron donor, tetrathiafulvalene (TTF). From the single-crystal crystallographic and spectroscopic studies, it was clarified that the nonstoichiometric deprotonation of anions and partial oxidation of TTFs occur, whereas the anion is electronically inert. Moderate conductivities of electron and proton were confirmed by dc and ac conductivity measurements. In addition, the electronic isolation of TTF wires was confirmed by the magnetic susceptibility data.