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Understanding the charge–discharge mechanism at the atomic-scale and the evolution of electrochemical properties for lithiated/de-lithiated compounds is a key challenge in lithium ion batteries (LIBs). Here, an innovative and viable protocol was addressed for the evolution of Li-ion intercalation and de-intercalation phenomena using electronic, thermal, mechanical, and electrochemical properties within the framework of DFT. The electronic property calculations are used to predict the band-gap engineering through the Al, Ca, and Cu-doping. Charge density and distribution analysis disclose that the Li-ions are diffused along the [101] direction and show wave-like pathways. Mechanical stability and superiority, provide a strong ability to withstand the volumetric and reversible change, against shear and bulk anisotropy during the charge–discharge cycle which reduces the micro cracking and capacity fading of LIBs. The thermal parameters are helpful in understanding the evolution of the chemical energy, structural disorder, and its spontaneous nature during the charge–discharge phenomenon. The electrochemical properties of the Li/Al-LTO half-cell predict an average voltage of 4.8 V, a theoretical capacity of 183.04 mA h g−1, and the volumetric energy and power densities of Li/Al-LTO are 0.366 W h cm−3 and 0.366 W cm−3, respectively. The gravimetric energy and power densities of Li/Al-LTO are 6.9 kW h kg−1 and 6.9 kW kg−1, respectively. The average voltage of the C6/Al-LTO full-cell is 5.4 V, and the oxidation, reduction potentials of C6/Al-LTO are 2.99, and 2.75 V, respectively. The calculated energy and power densities of C6/Al-LTO are 3.60 kW h kg−1 and 3.60 kW kg−1, respectively. This work sheds light on an innovative way to describe the charge–discharge mechanism and opens a new era of computational electrochemistry. [ABSTRACT FROM AUTHOR]

A redox-active donor–acceptor pair conjugated organic polymer (COP), TBB-phen, was synthesized via tetrakis(triphenylphosphine)palladium-catalyzed Sonogashira-coupling. It was modified further by stabilizing cobalt(II) into the organic polymer to create Co@TBB-phen. At room temperature, the polymers exhibited substantial charge separation, semiconducting behavior, and an embedded spherical morphology. Multi-point Brunauer–Emmett–Teller analysis revealed adequate surface area and mesoporosity (d = 2.7 nm). TBB-phen was explored for electrocatalysis, where it showed good oxygen reduction activity with a low onset potential of 0.78 V (vs. reversible hydrogen electrode) and low overpotential (332 mV@10 mA cm−2) towards the hydrogen evolution reaction (HER). However, Co@TBB-phen could deliver the oxygen evolution reaction (OER) along with amelioration of the oxygen reduction reaction (ORR) and HER. The overpotential for the ORR and HER was reduced by 30 mV and 33 mV, respectively, with oxygen evolution at 560 mV@10 mA cm−2. A study on natural bond orbitals revealed charge transfer and orbital interactions that confirmed the effective utilization of π-conjugation in the ORR and OER. Density functional theory (DFT) computations in the OER and HER provided a plausible reaction mechanism and descriptors, along with affirming that the designed polymer was an impeccable donor–acceptor pair. This work opens a door for phenanthroline molecules in electrochemical-energy applications. [ABSTRACT FROM AUTHOR]

A rapid microwave (180 s, 100 W) green approach has been demonstrated for the synthesis of TiO2 tripods (TITPs) using Mangifera indica leaf extracts. In this process, mangiferin acts as an efficient reducing agent while microwave radiations control the nucleation and growth of anisotropic TiO2 nanostructure. Surface morphological analyses reveal that synthesized TiO2 nanomaterial has a unique resilient shape of tripods with porosity. The photocatalytic ability of synthesized TITPs has been examined using Methylene blue (MB) as the target contaminant, and ∼75% (under visible light in 75 min) and 96% (under UV in 9 min) dye degradation has been achieved. The TITPs show recyclability for up to three cycles. Moreover, TITPs exhibit good adsorbent property that varies with the change of temperature and pH. The adsorption of the MB by TITPs follows the pseudo-first-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity of TITPs is found to be 17.54 mg/g based on the Langmuir model. The present multi-facet TITPs prepared via a simple and quick (180 s) microwave method has the potential for application in photocatalytic/adsorption for aqueous contaminant remediation. [ABSTRACT FROM AUTHOR]

A conjugated mesoporous polymer with a donor–acceptor approach (TBPA-phen) is synthesized via tetrakis(triphenylphosphine)palladium-catalyzed Sonogashira coupling and is exploited for in situ modification with cobalt (Co@TBPA-phen). The polymers exhibit a charge-separated state and semiconducting behavior at room temperature. The microscopy images reveal spherical morphology and multipoint Brunauer–Emmett–Teller analysis confirms the presence of mesoporosity (d = 2.6–4.5 nm). TBPA-phen exhibits significant electrochemical activity for the oxygen reduction reaction (ORR) with a low onset potential of 0.80 V vs. the reversible hydrogen electrode (RHE) and hydrogen evolution reaction (HER) with an overpotential of −486 mV @10 mA cm−2. But merely 6.3 wt% Co stabilized Co@TBPA-phen drives the oxygen evolution reaction (OER) at an overpotential of 480 mV @10 mA cm−2 along with the ORR (Eonset = 0.82 V vs. RHE) and HER (−335 mV @10 mA cm−2) at reduced overpotentials. Our density functional theory computations disclose the descriptor for every reaction along with validating that facilely synthesized polymers are exquisite donor–acceptor pairs. The natural bond orbital study provides orbital interactions and charge transfer in the ORR and OER and supports cobalt stabilized in Co@TBPA-phen in Co(0) and Co(II) states. A rechargeable Zn–air battery bestows an open circuit voltage of 1.51 V, a specific capacity of 723 mA h g−1, and a significant discharge potential of 1.2 V with no change in the voltage window of 0.75 V for up to 108 cycles. The study unravels strategically designed conjugated mesoporous polymers as efficient trifunctional electrocatalysts for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]

Micron thin films and microsupercapacitors based on polyvinyl alcohol, starch, methyl cellulose, and nickel acetate have been fabricated using the one-step formation of laser-induced graphene. Surface finishing of films and decomposition of nickel acetate to nickel oxide have been achieved with the help of CO2 laser. The optical studies of thin films and microsupercapacitors have been conducted, which are highly transparent in the UV–visible regime. There is no need of binders, current collectors, or separators in interdigitated microsupercapacitors. Starch-based microsupercapacitors (PSM) have superior electrochemical performance and stability than methyl cellulose (PMM) in the presence of 6-M KOH electrolyte. The maximum capacitance of PSM is 28.89 µF cm−2 in 6-M KOH at the scan rate of 1 mV s−1 from cyclic voltammetry. The specific energy density is 93.75 × 10−6 µWh cm−2 and the power density is 0.12 µW cm−2. The PMM has a specific capacitance of 2.5 nF cm−2 when compared to PSM of 0.52 µF cm−2 without electrolyte. The cycle life of PSM is 2500 cycles which shows its robustness. The performance of the microsupercapacitors is better than the other gate dielectric materials used in transistors and in the range for integration of energy storage devices in on-chip electronic and photonic devices. [ABSTRACT FROM AUTHOR]

A donor–acceptor pair-based redox-active conjugated mesoporous polymer (TPA-BZ) is synthesized herein via tetrakis-(triphenylphosphine)-palladium-catalyzed Sonogashira coupling using triphenylamine (TPA) and a benzaldehyde (BZ) derivative. The polymer exhibits the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) owing to its semi-conductive nature, adequate surface area, and mesoporosity. However, the functionality of the polymer is aggrandized when it is in-situ-modified with just 12.5 wt % cobalt nanoparticles (∼20–70 nm) to afford Co@TPA-BZ. It is observed that there is a reduction in band gap and an increase in surface area with much more refined pores aiding in enhanced electrode–electrolyte interaction. Co@TPA-BZ exhibits the oxygen evolution reaction along with enhanced ORR and HER. The intermolecular orbital interactions and subsequent charge transfer between reaction intermediates and polymers are elucidated by natural bond orbital analysis. Density functional theory computations provide a descriptor for reactions, clearly signifying the role of cobalt nanoparticles in the lowering of overpotentials and increase in the reaction kinetics. [ABSTRACT FROM AUTHOR]

Highly flexible, bendable, stretchable, and ultralightweight microwave absorbers (MA) that can handle harsh environments are essential for conformal surface coating in aerospace and defence industries. Hence, crystalline carbon nanotubes (CNTs) are grown on carbon fibers (CFs) using the chemical vapour deposition technique (CVD) and embedded in polyurethane (PU) to obtain MA. The fabricated MA is flexible, highly stretchable (>400%), has a low percolation threshold (0.1 wt %), ultralightweight (0.35 wt %), and thin nanocomposite for enhanced microwave absorber performance. The thickness of MA is optimized to achieve the impedance matching condition by utilizing the CST microwave studio simulation and verified experimentally. The minimum reflection loss (RL) of −52.53 dB with effective absorber bandwidth (EAB) covering the complete X band at a 2.4 mm thickness is obtained for just 0.35 wt % CFCNT. The negligible change in RL and EAB after 1000 bending cycles and 2 h of water-bath sonication confirms the operating efficiency of MA in harsh environmental conditions. The mechanism of microwave absorption in the case of CF and CFCNT-based MA is elucidated concerning microwave properties, electrical conductivity, and morphology. The CST microwave studio simulation is also extended from the X band to the Ku band (12.4–18 GHz) for broadband microwave absorber application. [ABSTRACT FROM AUTHOR]

We present a novel redox-active hybrid coordination polymer TPA-tpd-Co donor–acceptor pair, synthesized via Schiff-base condensation and self-assembly, where Co(II) is stabilized by triphenylamine and terpyridine ligand. The polymer exhibits a charge-separated state and semiconducting behavior at room temperature with an optical bandgap of 2.0 eV, indicating facile charge transfer. The microscopic images reveal irregular spherical morphology, and multi-point BET analysis showed substantial permanent porosity and surface area of 84.6 m2 g−1 (d = 3.1 nm), indispensable for channeled charge transfer during electrocatalysis. The powder XRD and HR-TEM unveil the presence of low-angle crystallinity in the polymer. With a low amount of cobalt (2.6 wt%) the polymer exhibits trifunctionality at a low onset potential of 0.80 V vs. RHE for the ORR, and overpotentials of 440 and 428 mV at 10 mA cm−2 for the OER (alkaline media), and HER (acidic media) with substantial stability for 12 hours in any pH environment. Our DFT computational studies gave the free energy for a plausible reaction mechanism and descriptors in conjunction with confirming that TPA-tpd-Co is an exquisite donor–acceptor pair with HOMO–LUMO positionings and a gap of 1.63 eV. The aqueous Zn–air battery also shows appreciable stability for 21 hours with a low voltage window of 1 V and an adequate specific capacity of 529 mA h g−1Zn. The observations inspire and suggest that TPA-based π-conjugated metal–organic coordination polymers pave the way for the development of a new and efficient tri-functional electrocatalyst. [ABSTRACT FROM AUTHOR]

Copper-based ternary metal oxide (i.e., Cu0.52Al0.01Fe0.47O4) impregnated reduced graphene oxide nanohybrid is verified for microbial and arsenic treatment. Growth inhibition of colonies are observed around 99.99% (E. coli), and 99.83% (S. aureus) at 10–20 μg/mL of hybrid dosage, respectively. The inhibition rates for both the colonies are increased to 99.9998% at 80 μg/mL. TEM images have shown insight of cell-content/lipid leakage behavior after inoculating with the hybrid. The efficient hindrance towards microbial colony growth is attributed to better charge transfer, reactive oxygen species generation, and metal-ion release. Maximum arsenic sorption capacities are observed around 248 and 314 mg/g for As(III), and As(V), respectively (Ci ~ 500 ppm). Surface morphology studies onto arsenic adsorption are reported with atomic force microscope, and FT-IR/Raman analysis. A detailed discussion onto individual spectra of As 3d spectra confirmed the occurrence of redox transformation in arsenic species [As(III)]. The variation in the quantity (at. %) of oxygen functional groups in O1s spectra (i.e., M–O, M-OH, and -OH2) onto the hybrid supported the ligand-exchange behavior. Cyclic voltammetry study in arsenic electrolytes (10 µM – 1 mM) provides the occurrence of various in-situ electrochemical reactions supporting the redox activity. A significant electromagnetic wave absorption characteristics of the present hybrid is proposed with plausible airborne antimicrobial-agent abilities. [ABSTRACT FROM AUTHOR]

This work exploits the advantage of asymmetric configuration over symmetric supercapacitor in designing high energy density flexible devices from two active electrode materials–keratin‐based renewable‐resource hierarchically porous carbon and hydrous ruthenium oxide (RuO2). The asymmetric device exhibits significantly high capacitance. Conventional estimation of energy storage parameters, however, cannot be applied for devices with a Faradaic energy storage contribution via redox charge transfer mechanism. Therefore, this work applies a precise measurement of pseudocapacitance contribution at various scan rates to correct the device data that reveals effective capacitance of 120 F g−1 with the energy density of 37 W h kg−1 at 776 W kg−1. It also retains excellent rate capability, >74% at high current density 25 A g−1. The charge storage activity and device stability can be further enhanced by introducing redox‐active electrolytes that improve specific capacitance, but the rate capabilities deteriorate at high current densities. Further, the principle of asymmetric electrode design is applied to fabricate a bending‐tolerant, flexible device by depositing active electrode material on wire‐shaped current collector followed by coupling those separated with polyvinyl alcohol gel containing redox electrolyte; it yields 36.8 mF cm−1 specific capacitance at a 0.2 mA cm−1 current density. [ABSTRACT FROM AUTHOR]

Lightweight, flexible, and thin nanocomposite structures providing enhanced electromagnetic interference (EMI) shielding in the desired frequency band are required for future generations of curved and bendable electronic devices. The present work deals with designing and developing such types of nanocomposite structures based on 2–8 wt% graphene nanoplatelets (GNPs) embedded in the polyurethane matrix. The GNP in the present situation is synthesized through the microwave intercalation technique followed by ultrasonication. It is observed that the 6 wt% of GNP (GNP6) having a density of 0.74 g/cc provides enhanced conductive and dielectric properties in the specified frequency band. The maximum value of total shielding effectiveness (SET) achieved here is 22.11 dB for GNP6 at 0.35 mm thickness. The strength of the proposed flexible structure is ascertained by measuring the SET of GNP6 after mechanically bending it for 500 cycles. The mechanism contributing to the high SET is explained based on their microstructure and frequency-dependent dielectric profile. The SET is numerically analyzed by simulation using the CST microwave studio in 8–18 GHz for broadband electromagnetic shielding application. The fabricated lightweight flexible nanocomposite structures show high EMI shielding, making them appropriate for conformal electronic packaging and thin coating in military and space applications. [ABSTRACT FROM AUTHOR]

In recent years, heteroatoms-doped graphene, with its exceptional properties, has generated significant advances in many fields of modern nanoscience and nanotechnology. With the rapid progress in doped graphene research, advanced graphene materials have been developed and frequently used in electromagnetic shielding applications. In this context, heteroatom-doping of graphene materials has been considered as an efficient strategy for the development of novel electromagnetic interference (EMI) shielding materials. This article aims to provide a timely update on the synthesis and EMI shielding applications of doped graphene materials. Heteroatom-doped and co-doped graphene-based materials (n-type and p-type doping) have been synthesized using various chemical and physical routes. Extensive approaches and strategies have been applied for achieving the intended doping/co-doping levels in graphene-based materials. Doping in graphene and its derivatives induces the formation of defects, changing the electrical conductivity as well as the mechanical properties. This results in an increase of reflection, and an improvement of absorption, enhancing shielding effectiveness. This review article provides a comprehensive overview of doping strategies for graphene and related composites, their EMI shielding performance, as well as comments on the future perspectives and possible challenges for doped graphene-based materials. We hope this review article offers a valuable starting point for researchers entering the field, providing an overview of synthesis approaches and EMI shielding applications. [ABSTRACT FROM AUTHOR]

The objective of this work was to grow carbon nanocoils (CNCs) on the glass fiber (GF) surface by chemical vapor deposition (CVD) and to prepare laminated composites by hand lay-Up, where CNC-coated GF is reinforcing phase. Spring-like CNCs were obtained at 600°C, whereas single helix CNCs were found over the glass fiber surface at 700°C. The presence of CNCs on the GF surface was confirmed using SEM analysis, TEM analysis, I–V analysis, etc. The CNC- coated GF-based epoxy composites were characterized for their mechanical properties. C7GE specimen showed lower mechanical properties compared to the GF epoxy specimens, while C6GE composite exhibited the best properties. Flexural strength and flexural modulus improved by about 35%, 56%, respectively, and storage modulus and glass transition temperature also increased by about 42% and 11%, respectively, compared to GF/epoxy specimen. SEM images exhibit good interaction between epoxy and GF when GF is modified by 600°C CNC. [ABSTRACT FROM AUTHOR]

In the present study, low defect density graphene nanosheets (GNs) have been synthesized via chemical reduction of exfoliated graphite (EG) in the presence of a green reducing agent, oxalic acID. EG has been synthesized via chemical intercalation of natural flake graphite followed by exfoliation through microwave irradiation at 800?W for 50?s. 50?mg/mL concentration of oxalic acID helps to extract low defect density GNs from EG. As-synthesized GNs have been characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, UV-Visible spectroscopy, field emission scanning electron microscopy, and X-ray photon spectroscopy. Raman analysis confirms the removal of oxygen functional groups from EG and achieved an ID/IG ratio of ∼0.10 with low defect density (∼1.12?×?1010?cm-2). Elemental analysis supports the Raman sIGnature of the removal of oxygen functionalities from EG, and a hIGh C/O ratio of ∼15.97 is obtained. Further, transparent conducting films (TCFs) have been fabricated by spray coating. The optical and electrical properties of fabricated TCFs have been measured after thermal graphitization. Thermal graphitization helps to improve the optical and electrical properties of TCFs by tuning the optical bandgap in a controlled way. TCF shows best performance when the film is annealed at 900?°C for 1?h in vacuum. It shows a sheet resistance of ∼1.10?kΩ/? and a transmittance of ∼71.56% at 550?nm. [ABSTRACT FROM AUTHOR]

Optimization of the transport properties of PbSe to maximize its thermoelectric performance at room temperature has been achieved through a combination of elemental doping and low densification. Al doped PbSe (PbSe:Alx; 0 ≤ x ≤ 0.06) with both lattice substitutional (Pb site) and interstitial occupation has been synthesized through solid state reaction. High Seebeck coefficient of ~300 to 400 μV/K is noticed at 300 to 500 K. This, combined with the lower thermal conductivity of ~1.20 W/m K, provides an improved ZT value as high as ~0.67 at 300 K to the PbSe:Alx Also, by substituting Al in PbSe, maximum power factors of ~20 to 26.6 μW/cm K² at 310 K are produced. The high room temperature thermoelectric performance of PbSe:Alx has been attributed to the mix contribution of the Al impurity states and the low densification. The strategy may be utilized to cost effective development of the low working temperature thermoelectric devices. [ABSTRACT FROM AUTHOR]

Multifunctional flexible films having properties of low filler dosing, light weight, small thickness, excellent environmental stability, and durability are highly demanded for absorption dominant electromagnetic interference (EMI) shielding in wearable electronic gadgets and in electronic packaging for civil, military, and space applications. For this, layered flexible films (FFs) of poly-(ethylene terephthalate) (PET), carbon nanofibers (CNFs), and polyurethane (PU) were fabricated. The sheet resistance decreased from 48.9 × 103 to 8.3 × 102 Ω/cm2 on increasing the CNF wt %, which resembled an improved 3D CNF network. This 3D CNF network was developed to achieve a total shielding efficiency (SET) of ∼25 dB (>99.9%) at 2 wt % for just 0.5 mm thickness of the film. Importantly, the fabricated film showed exceedingly consistent EMI shielding performance in a complex environment, with 22.9 dB and 23.6 dB SET values even after 1 h of ultrasonication treatment in water and 10 000 mechanical bending cycles, respectively. Conveniently, owing to the increased interfacial polarization, conduction loss, and multiple reflections, these FFs exhibited efficient EMI shielding accommodating the absorption dominant mechanism. The EMI shielding was also numerically analyzed through CST microwave studio software over the broad frequency range of 1–18 GHz. This work contributes to the fabrication and study of layered flexible films to enhance mechanical properties and achieve high absorption dominant EMI shielding for future-generation portable/wearable gadgets and packaging applications. [ABSTRACT FROM AUTHOR]

Polycrystalline lead selenide (PbSe) doped with copper (Cu) and nickel (Ni) was prepared to understand its magnetic behaviour and Raman activity. The processing conditions, influence of dopants (magnetically active and non-active) and their respective compositions on the magnetic properties and Raman active mode were studied. A surprising/anomalous room temperature ferromagnetism (hysteresis loop) is noticed in bulk diamagnetic PbSe, which is found to be natural or inherent characteristic of material, and depends on the crystallite size, dopant, and developed strain due to dopant/defects. The magnetic susceptibility (-1.71×10-4 emu/mol Oe) and saturated magnetic susceptibility (-2.74×10-4 emu/mol Oe) are found to be higher than the earlier reported value (diamagnetic: -1.0×10-4 emu/mol Oe) in bulk PbSe. With increase of Cu concentration (2% to 10%) in PbSe, the saturated magnetic susceptibility decreases from -1.22×10-4 to -0.85×10-4 emu/mol Oe. Whereas for Ni dopant, the saturated magnetic susceptibility increases to -2.96×10-4 emu/mol Oe at 2% Ni doped PbSe. But it further decreases with dopant concentration. In these doped PbSe, the shifting of longitudinal (LO) phonon mode was also studied by the Raman spectroscopy. The shifting of LO mode is found to be dopant dependent, and the frequency shift of LO mode is associated with the induced strain that created by the dopants and vacancies. This asymmetry in LO phonon mode (peak shift and shape) may be due to the intraband electronic transition of dopants. The variation in magnetic susceptibility and Raman shifts are sensitive to crystallite size, nature of dopant, concentration of dopants, and induced strain due to dopants. [ABSTRACT FROM AUTHOR]

In this research work, Carbon-carbon composites (CCCs) were fabricated via carbonization of carbon nanotubes (CNTs)-coated carbon textile (CNT-CF) reinforced polymer matrix composites (PMCs) preforms at 600, 900, 1200, and 1500 °C in a tubular furnace. To obtain CNT-CF, MWCNTs were produced radially on the surface of the nano-nickel particles plated carbon textile at 700°C using catalytic chemical vapor deposition method and C2H2 gas as a carbon source. The effects of CNT coating on carbon textiles were evaluated using FESEM, HR-TEM, XRD, Raman, TGA, and BET analysis. The effects of heat treatment temperatures on CNTs coated and uncoated PMCs manufactured using simple hand-layup method subsequently hot compressing were evaluated through XRD, FESEM, density, electrical conductivity measurement, tensile and flexural test, and viscoelastic properties using DMTA. The CNT coated CCCs obtained at 1500°C exhibited ∼ 66, 62, 83, 27, 44, 30, and 36% enhancement in electrical conductivity, storage modulus, loss modulus, tensile strength, Young's modulus, flexural strength, and flexural modulus of CNT coated CCCs, respectively compare to uncoated CCCs. Moreover, substantial enhancement in thermal stability of PMCs and CCCs make CNT-CF as one of the competent alternate reinforcement for the fabrication of structural parts used in high-performance applications. [ABSTRACT FROM AUTHOR]

The presented study stresses that the deposition temperature is an important parameter to determine the quality and properties of deposited Cu2O thin films on copper (Cu) and fluorine-doped tin oxide (FTO) substrates. The optical and electrical properties of chemical bath deposited (CBD) cuprous oxide (Cu2O) thin films with a variety of deposition temperatures (50, 60, 70, and 80 °C) have been extensively investigated. The X-ray diffraction studies reveal the cubic polycrystalline structure of deposited thin films. The scanning electron microscopy (SEM) exhibits a homogeneous thin film constituting Cu2O crystals for 60 °C. Optical studies show the least energy bandgap of 1.90 eV at the optimized deposition temperature. The Cu deposited Cu2O thin film possesses very little resistivity and higher charge carrier concentration mainly due to the contribution from the conducting Cu substrate. The Cu2O films exhibit p-type conductivity in addition to comparable Hall mobility and improved charge carrier concentration by two orders of magnitude in the case of FTO substrate (~ 1017 cm−3). The I–V characteristics of fabricated Schottky junction with the prepared optimized thin film is presented. This study establishes 60 °C as the optimum temperature for Cu2O thin film deposition on different substrates. [ABSTRACT FROM AUTHOR]

In the present study, carbon nanotubes (CNTs) were grown up on nickel‐coated carbon textiles utilizing acetylene gas as a carbon precursor in an isothermal CVD reactor. The effects of CNT coating time (0 to 25 min) in the carbon textile‐phenolic composites (CPCs) prepared via conventional hand‐layup technique followed by compression molding were assessed using microstructures, static and dynamic mechanical thermal analysis, density and electrical properties. Significant improvement was observed in static as well as dynamic mechanical properties and electrical properties for all the CNT coated samples. Though, 15 min coating time gives the optimum results. The results showed ~71, 74, 62, 67, 38, and 45% increment in storage modulus, loss modulus, flexural strength, flexural modulus, tensile strength, Young's modulus, respectively. Furthermore, huge improvement (707%) in electrical conductivity and significant enrichment in thermal stability mark CNTs coated carbon textile as the efficient alternative reinforcement for high‐performance thermo‐structural applications such as aerospace and automotive fields. [ABSTRACT FROM AUTHOR]

A donor–acceptor coordination polymer (TPA-Zn) was synthesized by Zn(II)-assisted self-assembly of an in situ generated triphenylamine (TPA) cored tristerpyridine ligand. The polymer absorbs a broad-spectrum of light and exhibits visible light-assisted hydrogen generation (27.1 mmol g−1 over 9 h) from water with 2.9% quantum efficiency at 400 nm. The microscopy images show a mesoscale fibrous morphology and the Brunauer–Emmett–Teller (BET) analysis reveals the porous nature of TPA-Zn (surface area: 234.5 m2 g; d = 6.98 nm), both of which are helpful for substrate diffusion during catalysis. [ABSTRACT FROM AUTHOR]

It is our great honor to dedicate this special issue of the I Journal of Applied Polymer Science i to Professor Anil K. Bhowmick in celebration of his 65th birthday. THERMOPLASTICS ELASTOMERS, POLYMER BLENDS, AND POLYMER MODIFICATION Thermoplastic elastomers are a class of materials that can be processed at high temperatures such as plastics but show rubbery behavior, like elastomers, at room temperature. Professor Bhowmick's work on compatibilization of rubber-rubber and rubber-plastics blends by phase modification to achieve desired properties is of commercial importance. FAILURE AND DEGRADATION OF POLYMERS Professor Bhowmick's pioneering experimental investigations on understanding the tearing behavior of polymers when the viscoelastic dissipation is minimized provided valuables insights on the mechanisms of reinforcement and adhesion. [Extracted from the article]

Polymer matrix composites reinforced with carbonous fillers are of significant commercial importance thanks to their vast application base. As the performance of such composites largely depends on matrix–filler interaction, the present study is focused on the impact of surface chemical states of polymer matrix and carbonous filler on the viscoelastic performance of the composites. Here we report investigation of the filler–matrix interface through spectroscopic techniques such as X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Viscoelastic properties of various polymer matrix composites prepared by varying the filler volume fraction and/or the matrix/filler type have been studied through dynamic mechanical thermal analysis. Further, to understand the matrix–filler interaction, correlations between viscoelastic parameters and various structural parameters such as the surface area of filler and the surface chemical states of filler/matrix obtained through XPS have been studied. Strong correlations between the viscoelastic parameters and the matrix/filler surface chemical states have been observed, suggesting the XPS as an important tool to study the role of the surface functionalities present on the matrix/filler surface to define the matrix–filler interaction. The filler surface functionalities such as C bound O have been found more compatible with the polymers having aromatic ring in the repeat unit. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48660. [ABSTRACT FROM AUTHOR]

BACKGROUND: Decontamination of water by means of photocatalysis is seen as a sustainable solution. However, catalysts with low recovery from liquid suspension remain the main predicament that obstructs their industrial applications. To overcome this shortcoming, a methodology is reported here for the functionalization of nanospinel nickel zinc ferrite by cystamine ligand to develop Ni0.5Zn0.5Fe2O4@cystamine magnetic recyclable catalyst for water decontamination applications. RESULTS: The diffraction patterns of bare and functionalized nanoferrites indicated that the cubic inverse spinel structure of the particles was not changed after cystamine functionalization. X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy analyses confirmed the chemical bonding between cystamine and spinel ferrites. The spherical morphology and elemental composition were studied through high‐resolution transmission electron spectroscopy (HRTEM) images and energy‐dispersive X‐ray (EDX) analysis respectively. Deeper understanding of the catalyst's optical behavior and calculation of the energy band gap were achieved by means of photoluminescence spectroscopy. Magnetic saturation values were calculated from vibrating sample magnetometer (VSM) analysis, and almost negligible change was found. A possible photocatalytic mechanism for the removal of organic dye is proposed. CONCLUSION: The present findings imply that the presence of amine groups on the catalyst surface, good dispersibility stability and outstanding catalytic activity make functionalized nanoferrite a suitable candidate for industrial wastewater treatment. Easy synthesis, easy work‐up and short reaction times are some of the advantages of the methodology. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The integration of nanomaterials with the micro-wave technology is a significant step toward the development of low-cost and low-power RF gas sensors. But, the issues associated with materials like insignificant surface area and poor conductivity, are barriers for the rapid detection of wide range of gas concentrations. In this paper, we demonstrate the proof-of concept using an RF complementary split ring resonator (CSRR) integrated ZnO/N-doped graphene (NGN) nano-hybrid to study the gas sensing properties. This RF device senses the presence of ammonia based on the change in the electrical conductivity of the nanohybrid material upon gas exposure. For this, we have designed and fabricated various new CSRR structures, namely, the meander (M-CSRR) and the CSRR, with the concentric-etched square pattern (SP-CSRR) other than the conventional CSRR (C-CSRR). The fabricated CSRRs are coated with the solvothermal methodically prepared ZnO/NGN nanomaterials and a comparison among them is also made. The comparison revealed that the SP-CSRR coated ZnO/NGN sensor had the maximum shift in the S21 resonance frequency ($\Delta \text {f}_{\mathbf {S21}} = 13$ MHz at 100 ppm) among all at room temperature. Furthermore, the SP-CSRR-ZnO/NGN sensor exhibited a large-S21 frequency shift of 133 MHz for 500 ppm of ammonia and has shown excellent reproducibility with 0.05% of variation. We have also projected the plausible sensing mechanism for this RF sensing device. [ABSTRACT FROM AUTHOR]

The effects of human hair‐derived porous carbon (HHC) as an eco‐friendly reinforcing filler in the carbon fabric‐reinforced phenolic matrix composites (CPCs) are evaluated through micro‐structural characterization studies, tensile, and flexural tests, dynamic mechanical analysis, density and electrical conductivity measurements. Various interfacial interaction parameters like reinforcement efficiency, C‐factor, adhesion factor, and so on are also calculated and compared for understanding the effects of HHC in composites. Conventional hand‐layup technique is used for impregnation of slurry made of phenolic resin and 0–50 wt% HHC on carbon fabric followed by stacking and curing through hot pressing to get laminates of CPCs. Significant improvement in mechanical, viscoelastic and electrical properties are observed over unfilled composite for all investigated HHC loadings. However, 30–40 wt% filler loading gives the optimum balance of properties. The results show ∼15, 93, 50, 85, and 132% increase in tensile strength, Young's modulus, flexural strength, flexural modulus, and storage modulus, respectively. Moreover drastic gain (1,500%) in electrical conductivity and substantial enhancement in thermal stability of CPCs make HHC as a cheap alternative reinforcing filler for structural composite applications working under thermo‐mechanical loads. POLYM. COMPOS., 40:E1573–E1587, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The presented studies concern the effects of graphite flake (GF) on the properties of a specific and challenging type of composite, that is, phenolic‐carbon fabric (PC) composites. This type of materials are commonly used in large scale, but the studies in this manuscript try to explain in detail the effects of graphite on the characteristics of composites. The results show that Young's modulus exhibits increasing trend however tensile strength and interlaminar shear strength show decrement on increasing the GF content in the PC‐GF composites. Dynamic mechanical thermal analysis (DMTA) reveals that storage modulus (E′) increases by ∼42% and 139% upon addition of 10 and 40 wt% GF in the PC‐GF composites, respectively. Loss modulus (E″) of the composites shows a drastic improvement (∼145%) upon addition of only 10 wt% GF. Moreover, various interfacial interaction parameters such as entanglement density (N), reinforcement efficiency factor (r), C factor (the effectiveness of fillers on the modulus of the composites), interphase adhesion factor (A), and 'b' factor (fiber volume correction factor) of the composites are also evaluated using the data obtained from DMTA and correlated with mechanical properties of the composites. POLYM. ENG. SCI., 58:1987–1998, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

In this work, the dielectric properties of epoxy-based composites are significantly improved with the help of the silicon carbide (SiC) filler at an operating frequency of 2.45 GHz to make them ideal candidates for microwave curing. The improvement is due to enhancement of the interfacial polarization because of the presence of the SiC filler. The dielectric properties are measured using the microwave cavity perturbation method. The cavity structure is simulated using the COMSOL@Multiphysics software to verify the measured data in terms of the resonant frequency. Finally, all the SiC-based composites including the neat epoxy resin are heated in the 2.45 GHz microwave oven at 300 W for 20 min. The thermal and mechanical properties of all the cured composites are measured, and the data are compared with their room temperature pre-cured counterparts. The dielectric properties of composite samples using SiC as a reinforcing agent in the epoxy are found to be substantially improved compared with those of the pure epoxy sample, which actually leads to better curing of these composite using the 2.45 GHz microwave system. [ABSTRACT FROM AUTHOR]