Rapid and sensitive in situ detection of heavy metals in fish using enhanced Raman spectroscopy.

Heavy metals have been widely applied in industry, agriculture, and other fields because of their outstanding physics and chemistry properties. They are non-degradable even at low concentrations, causing irreversible harm to the human and other organisms. Therefore, it is of great significance to develop high accuracy and sensitivity as well as stable techniques for their detection. Raman scattering spectroscopy and atomic absorption spectrophotometer (AAS) were used parallelly to detect heavy metal ions such as Hg, Cd, and Pb of different concentrations in fish samples. The concentration of the heavy metals is varied from 5 ppb to 5 ppm. Despite the satisfactory recoveries of AAS, their drawbacks are imperative for an alternative technique. In Raman scattering spectroscopy, the intensities and areas of the characteristic peaks are increased with increasing the concentration of the heavy metals. For Hg concentration ≥ 1 ppm, a slight shift is observed in the peak position. The obtained values of peak intensity and peak area are modeled according to Elvoich, Pseudo-first order, Pseudo-second order, and asymptotic1 exponential model. The best modeling was obtained using the Elovich model followed by the asymptotic1 exponential model. The introduced Raman spectroscopy-based approach for on-site detection of trace heavy metal pollution in fish samples is rapid, low-cost, and simple to implement, increasing its visibility in food safety and industrial applications.

Designing Thieno[3,4-c]pyrrole-4,6-dione Core-Based, A2-D-A1-D-A2-Type Acceptor Molecules for Promising Photovoltaic Parameters in Organic Photovoltaic Cells.

Nonfullerene-based organic solar cells can be utilized as favorable photovoltaic and optoelectronic devices due to their enhanced life span and efficiency. In this research, seven new molecules were designed to improve the working efficiency of organic solar cells by utilizing a terminal acceptor modification approach. The perceived A2-D-A1-D-A2 configuration-based molecules possess a lower band gap ranging from 1.95 to 2.21 eV compared to the pre-existing reference molecule (RW), which has a band gap of 2.23 eV. The modified molecules also exhibit higher λmax values ranging from 672 to 768 nm in the gaseous and 715-839 nm in solvent phases, respectively, as compared to the (RW) molecule, which has λmax values at 673 and 719 nm in gas and chloroform medium, respectively. The ground state geometries, molecular planarity parameter, and span of deviation from the plane were analyzed to study the planarity of all of the molecules. The natural transition orbitals, the density of state, molecular electrostatic potential, noncovalent interactions, frontier molecular orbitals, and transition density matrix analysis of all studied molecules were executed to validate the optoelectronic properties of these molecules. Improved charge mobilities and dipole moments were observed, as newly designed molecules possessed lower internal reorganization energies. The open circuit voltage (Voc) of W4, W5, W6, and W7 among newly designed molecules was improved as compared to the reference molecule. These results elaborate on the superiority of these novel-designed molecules over the pre-existing (RW) molecule as potential blocks for better organic solar cell applications.

Approach toward Low Energy Loss in Symmetrical Nonfullerene Acceptor Molecules Inspired by Insertion of Different π-Spacers for Developing Efficient Organic Solar Cells.

In this quantum approach, by adding bridge/π-spacer fragments between the donor and acceptor parts of a newly constructed DF-PCIC (A-D-A type) molecule, it is the aim to improve the photovoltaic characteristics of organic solar cells (OSCs). After π-spacer insertion into the reference molecule (DF-R), six new molecules (DF-M1 to DF-M6) were designed. The optoelectronic attributes of newly inspected molecules were theoretically calculated using MPW1PW91/6-31G(d,p) level of theory. All newly proposed molecules possessed a lower band gap (Eg), a higher value of absorption, lower reorganization energy, greater dipole moment, and lower energies of excitations than the DF-R molecule. The frontier molecular orbital study proclaimed that the DF-M1 molecule has the lowest band gap of 1.62 eV in comparison to the 2.41 eV value of DF-R. Absorption properties represented that DF-M1 and DF-M2 molecules show the highest absorption values of up to 1006 and 1004 nm, respectively, in the near-infrared region. Regarding the reorganization energy, DF-M2 has the lowest value of λe (0.0683896 eV) and the lowest value of λh (0.1566471 eV). DF-M2 and DF-M5 manifested greater dipole moments with the values of 5.514665 and 7.143434 D, respectively. The open circuit voltage (VOC) of all the acceptors was calculated with J61, a donor complex. DF-M4 and DF-M6 molecules showed higher values of VOC and fill factor than the DF-R molecule. Based on the given results, it was supposed that all the newly presented molecules might prove themselves to be better than the reference and thus might be of great interest to experimentalists. Thus, they are suggested to be used to develop proficient OSC devices with improved photovoltaic prospects in the near future.

Electrochemical properties of a novel EDLC derived from plasticized biopolymer based electrolytes with valuable energy density close to NiMH batteries.

This study introduces a novel system of solid electrolytes for electrical double-layer capacitors (EDLCs) utilizing biopolymer electrolytes with high energy density comparable to NiMH batteries. To prepare the electrolytes, a proton-conducting plasticized chitosan: poly(2-oxazoline) (POZ) with good film-forming properties was fabricated using a solution casting technique, and ammonium trifluoromethanesulfonate (NH4CF3SO3) salt was employed as a proton provider. Various glycerol concentrations were incorporated into the chitosan:POZ: NH4CF3SO3 system to enhance the ionic conductivity and fully transparent films were obtained. The impedance technique was utilized to determine the conductivity and measure the diffusion coefficient, mobility, and number density of ions. The electrochemical measurements, including linear sweep voltammetry (LSV) and cyclic voltammetry (CV), validated the high performance of the system. The EDLC was examined using galvanostatic charge-discharge (GCD) equipment, and the results revealed an energy density of 43 Wh/kg, specific capacitance of 300 F/g, and power density of 1800 W/kg over 500 cycles. These findings suggest that it is plausible to develop EDLCs that resemble batteries, making them a more desirable energy storage option for the industry.

High-Efficiency and Low-Energy-Loss Organic Solar Cells Enabled by Tuning the End Group Modification of the Terthiophene-Based Acceptor Molecules to Enhance Photovoltaic Properties.

In the current study, six nonfullerene small acceptor molecules were designed by end-group modification of terminal acceptors. Density functional theory calculations of all designed molecules were performed, and optoelectronic properties were computed by employing different functionals. Every constructed molecule has a significant bathochromic shift in the maximum absorption value (λmax) except AM6. AM1-AM4 molecules represented a narrow band gap (Eg) and low excitation energy values. The AM1-AM4 and AM6 molecules have higher electron mobility. Comparing AM2 to the reference molecule reveals that AM2 has higher hole mobilities. Compared to the reference molecule, all compounds have excellent light harvesting efficiency values compared to AM1 and AM2. The natural transition orbital investigation showed that AM5 and AM6 had significant electronic transitions. The open-circuit voltage (Voc) values of the computed molecules were calculated by combining the designed acceptor molecules with PTB7-Th. In light of the findings, it is concluded that the designed molecules can be further developed for organic solar cells (OSCs) with superior photovoltaic abilities.

Facile synthesis of carbon quantum dot/silver nanocomposite and its antimicrobial, catalytic and sensing applications.

Environmentally benign synthesis of nanocomposite, a pivotal facet of nanotechnology, and gaining prominence due to the increasing demand for facile, sustainable, and safe synthesis methods. The present research reports an facile/cost-effective method for the preparation of carbon dots (CDs) and carbon dot silver nanocomposites ( CD@AgNCs) via a hydrothermal treatment of peanut shells. The well-dispersed and spherical CDs with an average diameter of 5-6 nm were obtained and further employed for the preparation of CD@AgNCs. The formation of CD@AgNCs. was confirmed by optical and microscopic studies and ared shift in the λmax from 277 nm (CDs) to 450 nm (CD@AgNCs) with a size range of 30-40 nm was observed. The synthesized CD@AgNCs exhibit excellent catalytic potency for the reduction of 4-nitrophenol to 4-aminophenol, and also displaying a unique interaction and sensing ability towards heavy metal ions (Hg2+), causing a pronounced change in color from reddish-brown to transparent with limit of detection (LOD) of 23.47 ppm. Also, the prepared composite exhibit efficient antimicrobial potential against gram-negative (Escherichia coli) bacteria. Consequently, this study delves into a unified effective remediation platform with the integration of catalysis, sensing, and antimicrobial potentials.

Photoelectrochemical Green Hydrogen Production Utilizing ZnO Nanostructured Photoelectrodes.

One of the emerging and environmentally friendly technologies is the photoelectrochemical generation of green hydrogen; however, the cheap cost of production and the need for customizing photoelectrode properties are thought to be the main obstacles to the widespread adoption of this technology. The primary players in hydrogen production by photoelectrochemical (PEC) water splitting, which is becoming more common on a worldwide basis, are solar renewable energy and widely available metal oxide based PEC electrodes. This study attempts to prepare nanoparticulate and nanorod-arrayed films to better understand how nanomorphology can impact structural, optical, and PEC hydrogen production efficiency, as well as electrode stability. Chemical bath deposition (CBD) and spray pyrolysis are used to create ZnO nanostructured photoelectrodes. Various characterization methods are used to investigate morphologies, structures, elemental analysis, and optical characteristics. The crystallite size of the wurtzite hexagonal nanorod arrayed film was 100.8 nm for the (002) orientation, while the crystallite size of nanoparticulate ZnO was 42.1 nm for the favored (101) orientation. The lowest dislocation values for (101) nanoparticulate orientation and (002) nanorod orientation are 5.6 × 10-4 and 1.0 × 10-4 dislocation/nm2, respectively. By changing the surface morphology from nanoparticulate to hexagonal nanorod arrangement, the band gap is decreased to 2.99 eV. Under white and monochromatic light irradiation, the PEC generation of H2 is investigated using the proposed photoelectrodes. The solar-to-hydrogen conversion rate of ZnO nanorod-arrayed electrodes was 3.72% and 3.12%, respectively, under 390 and 405 nm monochromatic light, which is higher than previously reported values for other ZnO nanostructures. The output H2 generation rates for white light and 390 nm monochromatic illuminations were 28.43 and 26.11 mmol.h-1cm-2, respectively. The nanorod-arrayed photoelectrode retains 96.6% of its original photocurrent after 10 reusability cycles, compared to 87.4% for the nanoparticulate ZnO photoelectrode. The computation of conversion efficiencies, H2 output rates, Tafel slope, and corrosion current, as well as the application of low-cost design methods for the photoelectrodes, show how the nanorod-arrayed morphology offers low-cost, high-quality PEC performance and durability.

Synthesis and Characterization of Polymers Containing Ethynylene and Ethynylene-Thiophene Based Alternating Polymers Containing 2,1,3-Linked Naphthothiadiazole Units as Acceptor Linked with Fluorine as Donor: Electrochemical and Spectroscopic Studies.

The effect of ethynylene or ethynylene-thiophene spacers on the band gap of alternating polymers, containing 4,9-naphthothiadiazole units as an acceptor and 2,7-linked fluorene repeat units as a donor, were investigated. The Sonogashira coupling reaction was employed to prepare the two novel copolymers, namely ((9,9-dioctyl-fluorene)-2,7-diethynylene-alt-4,9-2,1,3-naphthothiadiazole (PFDENT) and poly(5,5'-(9,9-dioctyl-fluorene-2,7-diyl)bis(ethynyl-2-thienyl)-alt-4,9-(2,1,3-naphthothiadiazole) (PFDTENT). The optical, electrochemical and thermal properties of the two obtained polymers were widely investigated and compared. Both resulting polymers showed low solubility in common organic solvents and moderate molecular weights. It is believed that the introduction of acetylene linkers rather than acetylene-thiophene spacers on the polymer chains reduces the steric hindrance between the donor and acceptor units which leads to the adoption of more planar structures of polymeric chains, resulting in decreased molecular weights of the resulting conjugated polymers. Thus, both ethynylene-based polymers and ethynylene-thiophene-based polymers showed red-shifted absorption maxima compared to their counterpart (thiophene-based polymer), owing to the adoption of more planar structures. Optical studies revealed that the new ethynylene and ethynylene-thiophene-based polymers displayed low band gaps compared to their thiophene analogue polymer PFDTNT. Both resulting polymers showed good thermal stability. X-ray diffraction (XRD) patterns of both polymers revealed that PFDENT and PFDTENT possessed an amorphous nature in solid state.

Characteristics of Methyl Cellulose Based Solid Polymer Electrolyte Inserted with Potassium Thiocyanate as K+ Cation Provider: Structural and Electrical Studies.

The attention to a stable and ionic conductive electrolyte is driven by the limitations of liquid electrolytes, particularly evaporation and leakage, which restrain their widespread use for electrochemical device applications. Solid polymer electrolyte (SPE) is considered to be a potential alternative since it possesses high safety compared to its counterparts. However, it still suffers from low device efficiency due to an incomplete understanding of the mechanism of ion transport parameters. Here, we present a simple in situ solution casting method for the production of polymer-based electrolytes using abundantly available methylcellulose (MC) doped at different weight percentages of potassium thiocyanate (KSCN) salt. Fourier transform infrared (FTIR), and electrochemical impedance spectroscopy (EIS) methods were used to characterize the prepared samples. Based on EIS simulation and FTIR deconvolution associated with the SCN anion peak, various ion transport parameters were determined. The host MC medium and KSCN salt have a strong interaction, which was evident from both peak shifting and intensity alteration of FTIR spectra. From the EIS modeling, desired electric circuits correlated with ion movement and chain polarization were drawn. The highest ionic conductivity of 1.54 × 10-7 S cm-1 is determined from the fitted EIS curve for the film doped with 30 wt.% of KSCN salt. From the FTIR deconvoluted peak, free ions, ions in contact with one another, and ion aggregates were separated. The extracted ion transport parameters from the EIS method and FTIR spectra of the SCN anion band confirm that both increased carrier concentration and their mobility were crucial in improving the overall conductivity of the electrolyte. The dielectric investigations were further used to understand the conductivity of the films. High dielectric constants were observed at low frequencies for all MC:KSCN systems. The dispersion with a high dielectric constant in the low-frequency band is ascribed to the dielectric polarization. The wide shift of M″ peak towards the high frequency was evidenced by the MC-based electrolyte impregnated with 30 wt.% of KSCN salt, revealing the improved ionic movement assisted with chain segmental motion. The AC conductivity pattern was influenced by salt concentration.

Study of MC:DN-Based Biopolymer Blend Electrolytes with Inserted Zn-Metal Complex for Energy Storage Devices with Improved Electrochemical Performance.

Stable and ionic conducting electrolytes are needed to make supercapacitors more feasible, because liquid electrolytes have leakage problems and easily undergo solvent evaporation. Polymer-based electrolytes meet the criteria, yet they lack good efficiency due to limited segmental motion. Since metal complexes have crosslinking centers that can be coordinated with the polymer segments, they are regarded as an adequate method to improve the performance of the polymer-based electrolytes. To prepare plasticized proton conducting polymer composite (PPC), a simple and successful process was used. Using a solution casting process, methylcellulose and dextran were blended and impregnated with ammonium thiocyanate and zinc metal complex. A range of electrochemical techniques were used to analyze the PPC, including transference number measurement (TNM), linear sweep voltammetry (LSV), cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The ionic conductivity of the prepared system was found to be 3.59 × 10-3 S/cm using the EIS method. The use of glycerol plasticizer improves the transport characteristics, according to the findings. The carrier species is found to have ionic mobility of 5.77 × 10-5 cm2 V-1 s-1 and diffusion coefficient of 1.48 × 10-6 cm2 s-1 for the carrier density 3.4 × 1020 cm-3. The TNM revealed that anions and cations were the predominant carriers in electrolyte systems, with an ionic transference value of 0.972. The LSV approach demonstrated that, up to 2.05 V, the film was stable, which is sufficient for energy device applications. The prepared PPC was used to create an electrical double-layer capacitor (EDLC) device. The CV plot exhibited the absence of Faradaic peaks in the CV plot, making it practically have a rectangular form. Using the GCD experiment, the EDLC exhibited low equivalence series resistance of only 65 Ω at the first cycle. The average energy density, power density, and specific capacitance values were determined to be 15 Wh/kg, 350 W/kg, and 128 F/g, respectively.

Electrochemical and Ion Transport Studies of Li+ Ion-Conducting MC-Based Biopolymer Blend Electrolytes.

A facile methodology system for synthesizing solid polymer electrolytes (SPEs) based on methylcellulose, dextran, lithium perchlorate (as ionic sources), and glycerol (such as a plasticizer) (MC:Dex:LiClO4:Glycerol) has been implemented. Fourier transform infrared spectroscopy (FTIR) and two imperative electrochemical techniques, including linear sweep voltammetry (LSV) and electrical impedance spectroscopy (EIS), were performed on the films to analyze their structural and electrical properties. The FTIR spectra verify the interactions between the electrolyte components. Following this, a further calculation was performed to determine free ions (FI) and contact ion pairs (CIP) from the deconvolution of the peak associated with the anion. It is verified that the electrolyte containing the highest amount of glycerol plasticizer (MDLG3) has shown a maximum conductivity of 1.45 × 10-3 S cm-1. Moreover, for other transport parameters, the mobility (µ), number density (n), and diffusion coefficient (D) of ions were enhanced effectively. The transference number measurement (TNM) of electrons (tel) was 0.024 and 0.976 corresponding to ions (tion). One of the prepared samples (MDLG3) had 3.0 V as the voltage stability of the electrolyte.

The Use of Synthesized CoO/Co3O4 Nanoparticles as A Corrosion Inhibitor of Low-Carbon Steel in 1 M HCl.

CoO/Co3O4 nanoparticles (CoO/Co3O4 NPs) were synthesized with egg white. The effectiveness of CoO/Co3O4 NPs to inhibit the corrosion of carbon steel has verified in acidic medium (1 M HCl). It has been found that Langmuir adsorption isotherm is the dominant adsorption process of CoO/Co3O4 NPs on the surface of low-carbon steel. The thermodynamic parameters also demonstrated that the adsorption process of CoO/Co3O4 NPs was a physicochemical, spontaneous, and exothermic process. The electrochemical impedance spectroscopy technique and potentiodynamic polarization were applied. The results obtained in this study showed that CoO/Co3O4 NPs acted as a mixed inhibitor for the anodic reaction and the cathodic reaction, and the efficiency to inhibit the corrosion was 93% at 80 ppm of the inhibitor. The results of scanning electron microscopy (SEM) technique, energy-dispersive X-ray spectroscopy (EDS), and X-ray electron spectroscopy (XPS) confirmed the effectiveness that was obtained using the inhibitor to protect the surface of low carbon steel. Thus, low-carbon steel can be protected against corrosion in acidic medium using CoO/Co3O4 NPs as inhibitors.

Interfacial nanoarchitectonics for ZIF-8 membranes with enhanced gas separation.

Metal-organic framework (MOF) membranes are potentially useful in gas separation applications. Conventional methods of MOF membrane preparation require multiple steps and high-pressure conditions. In this study, a reliable one-step interfacial synthesis method under atmospheric pressure has been developed to prepare zeolitic imidazolate framework-8 (ZIF-8) membranes supported on porous α-Al2O3 disks. To obtain optimal ZIF-8 membranes, three reaction parameters were investigated, namely, reaction temperature, reaction time, and concentration of the organic linker (i.e., 2-methylimidazole). The growth of ZIF-8 membranes under various parameters was evaluated by field-emission scanning electron microscopy, and the optimal synthesis conditions were determined (i.e., 80 °C for 12 h in 50 mM of 2-methylimidazole). The as-synthesized ZIF-8 membranes were then applied to CO2/N2 gas separation, which exhibited a maximum separation factor of 5.49 and CO2 gas permeance of 0.47 × 10-7 mol·m-2·s-1·Pa-1.

Studies of Circuit Design, Structural, Relaxation and Potential Stability of Polymer Blend Electrolyte Membranes Based on PVA:MC Impregnated with NH4I Salt.

This work presents the fabrication of polymer electrolyte membranes (PEMs) that are made of polyvinyl alcohol-methylcellulose (PVA-MC) doped with various amounts of ammonium iodide (NH4I). The structural and electrical properties of the polymer blend electrolyte were performed via the acquisition of Fourier Transform Infrared (FTIR) and electrical impedance spectroscopy (EIS), respectively. The interaction among the components of the electrolyte was confirmed via the FTIR approach. Electrical impedance spectroscopy (EIS) showed that the whole conductivity of complexes of PVA-MC was increased beyond the addition of NH4I. The application of EEC modeling on experimental data of EIS was helpful to calculate the ion transport parameters and detect the circuit elements of the films. The sample containing 40 wt.% of NH4I salt exhibited maximum ionic conductivity (7.01 × 10-8) S cm-1 at room temperature. The conductivity behaviors were further emphasized from the dielectric study. The dielectric constant, ε' and loss, ε'' values were recorded at high values within the low-frequency region. The peak appearance of the dielectric relaxation analysis verified the non-Debye type of relaxation mechanism was clarified via the peak appearance of the dielectric relaxation. For further confirmation, the transference number measurement (TNM) of the PVA-MC-NH4I electrolyte was analyzed in which ions were primarily entities for the charge transfer process. The linear sweep voltammetry (LSV) shows a relatively electrochemically stable electrolyte where the voltage was swept linearly up to 1.6 V. Finally, the sample with maximum conductivity, ion dominance of tion and relatively wide breakdown voltage were found to be 0.88 and 1.6 V, respectively. As the ions are the majority charge carrier, this polymer electrolyte could be considered as a promising candidate to be used in electrochemical energy storage devices for example electrochemical double-layer capacitor (EDLC) device.

Innovative Green Chemistry Approach to Synthesis of Sn2+-Metal Complex and Design of Polymer Composites with Small Optical Band Gaps.

In this work, the green method was used to synthesize Sn2+-metal complex by polyphenols (PPHs) of black tea (BT). The formation of Sn2+-PPHs metal complex was confirmed through UV-Vis and FTIR methods. The FTIR method shows that BT contains NH and OH functional groups, conjugated double bonds, and PPHs which are important to create the Sn2+-metal complexes. The synthesized Sn2+-PPHs metal complex was used successfully to decrease the optical energy band gap of PVA polymer. XRD method showed that the amorphous phase increased with increasing the metal complexes. The FTIR and XRD analysis show the complex formation between Sn2+-PPHs metal complex and PVA polymer. The enhancement in the optical properties of PVA was evidenced via UV-visible spectroscopy method. When Sn2+-PPHs metal complex was loaded to PVA, the refractive index and dielectric constant were improved. In addition, the absorption edge was also decreased to lower photon. The optical energy band gap decreases from 6.4 to 1.8 eV for PVAloaded with 30% (v/v) Sn2+-PPHs metal complex. The variations of dielectric constant versus wavelength of photon are examined to measure localized charge density (N/m*) and high frequency dielectric constant. By increasing Sn2+-PPHs metal complex, the N/m* are improved from 3.65 × 1055 to 13.38 × 1055 m-3 Kg-1. The oscillator dispersion energy (Ed) and average oscillator energy (Eo) are measured. The electronic transition natures in composite films are determined based on the Tauc's method, whereas close examinations of the dielectric loss parameter are also held to measure the energy band gap.

Impedance and Dielectric Properties of PVC:NH4I Solid Polymer Electrolytes (SPEs): Steps toward the Fabrication of SPEs with High Resistivity.

In the present article, a simple technique is provided for the fabrication of a polymer electrolyte system composed of polyvinyl chloride (PVC) and doped with varying content of ammonium iodide (NH4I) salt using solution-casting methodology. The influences of NH4I on the structural, electrochemical, and electrical properties of PVC have been investigated using X-ray diffraction, electrochemical impedance spectroscopy (EIS), and dielectric properties. The X-ray study reveals the amorphous nature of the polymer-salt complex. The EIS measurement revealed an ionic conductivity of 5.57 × 10-10 S/cm for the electrolyte containing 10 wt.% of salt. Our hypothesis is provided, which demonstrated the likelihood of designing highly resistive solid electrolytes using the concept of a polymer electrolyte. Here, the results showed that the resistivity of the studied samples is not dramatically decreased with increasing NH4I. Bode plots distinguish the decrease in resistance or impedance with increasing salt contents. Dielectric measurements revealed a decrease in the dielectric constant with the increase of NH4I content in the PVC polymer. The relaxation time and dielectric properties of the electrolytes confirmed their non-Debye type behavior. This pattern has been validated by the existence of an incomplete semicircle in the Argand plot. Insulation materials with low εr have found widespread applications in electronic devices due to the reduction in delay, power dissipation, and crosstalk. In addition, an investigation of real and imaginary parts of electric modulus leads to the minimized electrode polarization being reached.

The Study of Ion Transport Parameters in MC-Based Electrolyte Membranes Using EIS and Their Applications for EDLC Devices.

A solution cast technique was utilized to create a plasticized biopolymer-based electrolyte system. The system was prepared from methylcellulose (MC) polymer as the hosting material and potassium iodide (KI) salt as the ionic source. The electrolyte produced with sufficient conductivity was evaluated in an electrochemical double-layer capacitor (EDLC). Electrolyte systems' electrical, structural, and electrochemical properties have been examined using various electrochemical and FTIR spectroscopic techniques. From the electrochemical impedance spectroscopy (EIS), a maximum ionic conductivity of 5.14 × 10-4 S cm-1 for the system with 50% plasticizer was recorded. From the EEC modeling, the ion transport parameters were evaluated. The extent of interaction between the components of the prepared electrolyte was investigated using Fourier transformed infrared spectroscopy (FTIR). For the electrolyte system (MC-KI-glycerol), the tion and electrochemical windows were 0.964 and 2.2 V, respectively. Another electrochemical property of electrolytes is transference number measurement (TNM), in which the ion predominantly responsibility was examined in an attempt to track the transport mechanism. The non-Faradaic nature of charge storing was proved from the absence of a redox peak in the cyclic voltammetry profile (CV). Several decisive parameters have been specified, such as specific capacitance (Cs), coulombic efficiency (η), energy density (Ed), and power density (Pd) at the first cycle, which were 68 F g-1, 67%, 7.88 Wh kg-1, and 1360 Wh kg-1, respectively. Ultimately, during the 400th cycle, the series resistance ESR varied from 70 to 310 ohms.

Antibacterial potency, cell viability and morphological implications of copper oxide nanoparticles encapsulated into cellulose acetate nanofibrous scaffolds.

It is generally believed that the most challenging impediment for the utilization of cellulose acetate (CA) in the medical field is its hydrophobicity and disability to poison the harmful microbes. Therefore, in this contribution, we aimed to prepare an environmentally scaffold-based CA loaded with copper nanoparticles (CuONPs), which are expected to not only improve the hydrophilicity of the prepared nanofibers, but also have an effective ability to kill such harmful and infectious microbes that are abundant in wounds. The obtained results attested that the generated nanofibers became thicker with increasing the content of CuONPs in CA nanofibers. The roughness average increased from 143.2 to 157.1 nm, whereas the maximum height of the roughness (Rt) increased from 400.8 to 479.9 nm as going from the lowest to the highest content of CuONPs. Additionally, the contact angle of the prepared nanofibers decreased from 105.3° (CA alone) to 85.4° for CuONPs@CA. Significantly, biological studies revealed that cell viability and anti-bacterial potency were improved upon incorporating CuONPs into CA solution. Correspondingly, their inhibition zones reached 18 ± 3 mm, and 16 ± 2 mm for nanofibrous scaffolds having 12.0CuO@CA, besides raising the cell viability from 91.3 ± 4% to 96.4 ± 4% for 0.0CuO@CA, and 12.0CuO@CA, respectively, thereby implying that the fabricated CuONPs@CA nanocomposite has biocompatibility towards fibroblast cells. Thus, introducing biological activity into CA nanofibers via loading with CuONPs makes it suitable for numerous biomedical applications, particularly as an environmentally benign wound dressing fibers.

Chitosan polymer complex derived nanocomposite (AgNPs/NSC) for electrochemical non-enzymatic glucose sensor.

N/S-doped carbon supported AgNPs has been synthesized at low-cost, and scalable method using silver complex of chitosan based polymer. The fabricated nanocomposites exhibited excellent electrocatalytic performance as a glucose sensor. Remarkably, the fabricated glucose sensor is exhibited an ultrahigh sensitivity of 35.22 mAmM-1 cm-2 with a very low detection limit (0.046 mM) and long-term durability (30 days). Under optimized conditions, a wide linear response was obtained from 5 µM to 3 mM with an excellent linear response (R2 = 0.9940) was also obtained by AgNPs/NSC modified electrode. The presence of the heteroatom and AgNPs into the carbon matrix greatly enhances the selectivity for glucose over potential interferences in aqueous solution, with interfering agents. Overall, the present methodology demonstrates an efficient, robust, and aqueous-media-tolerable nanocomposite material as an electrochemical sensor and a potential alternative tool for the detection of glucose.