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Background: Kraton/polyaniline ionomer is synthesized and further characterized by electrochemical studies to check the redox properties of the material. Ion exchange capacity, proton conductivity, and selectivity of the synthesized membrane were determined. And found that the membrane was selective for Cu (II) ions. Methods: The dry Kraton membranes were weighed and kept in 25 mL of 10 % prepared aniline solution in a conical flask for 5, 10, 15, and 20 minutes below 10 0C for socking. The prepared solution of 30 mL of 0.1 M potassium peroxydisulfate was added in a conical flask at constant stirring below 10 0C for half an hour. Finally, the aluminum foil-covered conical flask was kept in the refrigerator for 24 h and modified Kraton membranes were weighed again before carrying out further studies. Results: The membrane was characterized by some physicochemical methods like SEM, TGA, T-IR, IEC, proton conductivity and selectivity sorption studies. An ionomeric membrane of Kraton polymer was developed as reported earlier. Kraton membrane showed the IEC of 1.9 meq·g-1. The FTIR spectrum of Kraton/PANI film reveals that weight loss up to 400°C may be found because of the thermal degradation of composite substances. Conclusion: Ion-selective potentiometric was carried out using the self-prepared ion-selective membrane electrode. The membrane was prepared by solution casting method. The membrane was characterized by some physicochemical methods like SEM, TGA, T-IR, IEC, proton conductivity and selectivity sorption studies. On the basis of selectivity studies, the composite material was found selective for Cu (II) ion. A copper ISME was successfully fabricated using the solution casting method. The ISME possessed good selectivity, linearity, working pH range, and response time which was also used as an indicator electrode for the titration of copper using EDTA.

The FeZnO (iron zinc bimetallic oxide) was synthesised using the ultrasound-assisted method and further converted into FeZnOAC (iron zinc bimetallic oxide-doped activated carbon) by treating it with activated carbon. As developed FeZnOAC is effectively used for the adsorption of Fuchsine dye from an aqueous dye solution. A 200 mg of FeZnOAC was sufficient for the rapid removal of Fuchsine (>97.64%) dye. The kinetic adsorption data is well fitted with a pseudo-second-order model. The Langmuir isothermal model shows a high regression coefficient (R2) than the Freundlich with a Qmax of 333.33 mg g−1. The dye adsorption at varying temperatures (i.e. 298–318 K) was based on a multi-layered statistical physics model. The n value (n

The prospective of this work is to synthesize a new nanocomposite that serves as an electrode material for the immobilization of biomolecules. In this work surface-functionalized single-walled carbon nanotubes (f–COOH–SWCNTs), and hydrothermally synthesized surface defected 2D nanoplates wrapped by polpyrrole matrix was developed. The developed nanocomposite was utilized as the anode material for the immobilization of enzymes. Nanocomposite f-SWCNTs@Ppy@NiMoSe2 was characterized by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the electrochemical methods including cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). The electrochemically controlled bioanode reached to the open circuit potential (OCV) of 0.35 V and delivered the maximum current density of 9.01 mA cm−2 in 50 mM glucose concentration prepared in phosphate buffer solution (PBS) (pH 7.0) as the testing solution at 100 mVs−1 scan rates.

Fischer-Tropsch (FT) process has great potential to accomplish energy security but also for utilizing greenhouse gases to address the energy problem. Different kinds of feedstocks like coal, biomass (via gasification), CO2, methane (via reforming), and nonconventional energy sources are used to obtain the syn-gas (CO and H2). The formation of hydrocarbons in the FT process follows ASF distribution over the majority of the catalysts. It can be overcome by the application of a suitable catalyst, controlling the active metal interaction with the support and interaction of formed hydrocarbon with the support. The ratio of syn-gas is important to maintain the desired conversion and to have more selectivity towards C5+ products. Increase in the H2: CO ratios in the feed increases C5+ products and methane decreases. Whereas with the decrease in the ratios increases undesirable reactions and methane formation. In this article, we have discussed the recent literature from the viewpoint of increasing the C5+ selectivity. Support has a profound influence on product distribution. With the application of suitable support and controlling the interaction of the active sites yields the good CO conversion with fewer lighters and higher C5+ hydrocarbons.

Colorimetric and ratiometric fluorescent probe for cations gain very well attention by the chemist, biologist and environmentalist. Metals has two sides, first is biolgical active for living creature and toxic nature for the ecosystem. From last three decades the scientists are contiously trying to find out the best solution for the detection of cations at micro as well as nanomolar levels. In the present review we discussed the colorimetric and ratiometric fluorescent probe synthesized by the authors in almost half decade.

Enzymatic biofuel cells (EBFCs) produce electrical energy from green and renewable fuels, by utilizing redox enzyme. However, the main issue of low power output and stability of the electrode still prevails in this field. Extensive research is going on to overcome this problem by improving the electrical communication between the enzyme and the current collector. In the light of this, a new electrode design based on reduced graphene oxide (rGO) and functionalized magnetic nanoparticles (f-Fe3O4 NPs) in polyaniline matrix has been proposed and employed for the purpose of the EBFCs application, in order to achieve efficient electron shuttling between enzyme glucose oxidase (GOx) and the electrode surface. The as-prepared rGO/PANI/f-Fe3O4 nanocomposite was examined by analytical techniques viz, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the electrochemical behaviour of the rGO/PANI/f-Fe3O4 nanocomposite and rGO/PANI/f-Fe3O4/Frt/GOx bioanode was determined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV). The bioanode attained a maximum current density of 32.9 mA cm−2 at the optimum glucose concentration of 50 mM.

Poly(3,4-ethylene dioxythiophene): polystyrene sulfonate (PEDOT: PSS) zirconium(IV) phosphate (ZrP) based ionomeric membrane was prepared by a solution-casting method. Subsequently, aniline polymerization was carried out on the surface of the membrane by oxidative chemical polymerization. It was characterized by thermogravimetric analysis/differential thermal analysis/differential thermogravimetry (TGA/DTA/DTG), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis, and Fourier-transform infrared (FTIR) spectroscopy. The membrane was also characterized by ion-exchange properties. The tip displacement investigation of the ionomeric membrane was also carried out. The outcomes demonstrated that the manufactured ionomeric membrane could produce generative strengths (tip powers), and consequently create good displacement. In this manner, the proposed ionomeric membrane was found proper for bending movement actuator that will give a successful and promising stage for smaller-scale mechanical applications.

In the past few decades, the scientific community have used aqueous solutions as the media for enzyme and whole cell biocatalysis reactions, but nonaqueous media also play a significant role in biocatalytic reactions, for example, in biotransformation technology. The design and discovery of efficient biocatalysis and has made tremendous progress for various synthetic applications in recent years. Versatile nonaqueous “green” solvents have been used in biocatalysis and are divided into three major solvent systems: ionic liquids (ILs), supercritical fluids (SCFs), and organic solvents. Recent works explain that enzymatic reactions in nonaqueous media offer new prospects for the production of useful chemicals such as surfactants, peptides and proteins, emulsifiers, wax, biopolymers, chiral drug molecules, etc. Compared with aqueous solvents, the feasibility of enzymatic reactions in nonaqueous solvents offers various potential aspects for biotechnological production. Biocatalysis also plays a key role in the production of various compounds with applications in the chemical and pharmaceutical industries. In this chapter, we will discuss biocatalytic reactions and the role of nonaqueous solvents.

Water borne polyurethanes have gained significant attention due to high-performance, excellent elasticity, no toxicity, abrasion resistance, adhesion functionality, flexibility, environmental friendliness, and broad substrate suitability. The physiochemical properties of water borne polyurethanes include low temperature, one component application, low viscosity, low solubility, and excellent coating performance. Therefore, this chapter intends to provide a detailed information sustainable production and applications of water borne polyurethanes. Different techniques such as thermal gravimetric analysis, Fourier transform infrared spectroscopy, mechanical measurements, and dynamic thermomechanical analysis used for the characterization of water borne polyurethanes were also highlighted. Moreover, detailed information on the application of water borne polyurethane plus polyurethane-urea dispersions for the production of novel eco-friendly nanomaterials were also highlighted.

In current research, solid-state materials are often used as the most promising materials for hydrogen storage materials in comparison of the other storage materials. Hydrogen is considered as an important source of energy storage system for automotive applications. Hydrogen as a conventional fuel offers high potential benefits due to their easily storage and transportation and considered as an alternative fuel because of its natural abundance and a clean and sustainable energy carrier. It is available in abundance and is the renewable sources of energy and, more significantly, is a clean fuel. Metal hydrides are able to store relatively large amounts of hydrogen in a solid phase as compared with other solid-state materials with safety and long-term stability. This perspective chapter highlights the brief idea about the various solid-state materials as storage of hydrogen and various applications in energy fields.

Biocatalysis is an efficient method that can be used to produce fine chemicals such as carbohydrates, proteins, vitamins, amino acids, esters, agrochemicals, chiral pharmaceuticals, etc., by enzymatic biotransformations on an industrial scale. Today, ionic liquids (ILs) are important media for the synthesis of these chemicals, which have been studied by the scientific community for the last few decades. ILs successfully replace conventional organic solvents in a range of isolated enzyme bioconversions due to various possible cation-anion combinations that show its hydrophobicity/hydrophilicity characteristics. These behaviors allow facilitating the reaction solvents with peculiar properties and also supply an opportunity to carry out various excellent biocatalytic reactions. The enzymatic reactions occurring in ILs show a lot of advantages such as better enzyme stability, high conversion rates, recyclability, and high enantioselectivity compared with other conventional organic solvents in observed reactions. The present work emphasizes the various biocatalytic reactions in hydrophobic/hydrophilic ILs.

A simple, scalable, novel polymer was synthesized by the aminolysis of poly(styrene-co-maleic anhydride) cumene terminated (PSMAC) using p-aminohippuric acid. The main objective was to perceive the effect of blend ratio of polysulfone (PSF) and poly[styrene-alt-(N-4-benzoylglycine-maleamic acid)] cumene terminated (PAH) on morphology and permeation properties of the membranes. The PSF/PAH blend membranes unveiled enriched hydrophilicity, porosity, zeta potential, water uptake and permeability owing to the existence of the hydrophilic PAH. However, the contact angle was not diminished over 20% of PAH ratio as there was an increase of hydrophobic alkyl group density. Differential scanning calorimetry (DSC) was employed for the determination of the glass transition temperature of the blends and the results revealed that the polymer blend is miscible in nature. Moreover, the M-3 membrane was screened for the heavy metal ion removal and achieved removal of 91.5% of Pb2+ and 72.3% of Cd2+ ions, respectively. The adsorption parameters indicated that the Langmuir isotherm model fits well for both Pb2+ and Cd2+ ions adsorption on M-3 membrane. The adsorption capacity attained from Langmuir isotherm model was 19.35 and 9.88 mg/g for Pb2+ and Cd2+ ions correspondingly.

In this study, a bioanode for biofuel cells was produced using a composite of poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) and sulfonated graphene oxide (SGO) wherein SGO shows synergistic impact by going about as charge adjusting dopant and a conductive filler. The conducting polymer PEDOT:PSS alongside SGO fill in as a way to encourage electron transfer and co-immobilize the enzyme in the meantime. Extensive surface area controlled by SGO prompts high catalyst stacking and empowers to enhance the current density of the fuel cells. Ferritin additionally upgrades the transportation of electrons by going about as a redox mediator that effectively transfers electrons from enzyme to the conducting support. Examination of electrochemical execution of modified bioanode in presence of glucose was completed by cyclic voltammetry (CV) and linear sweep voltammetry (LSV) at various scan rates (20–100 mV s−1) in 35 mM of glucose concentrations prepared in 0.3 M potassium ferrocyanide [K4Fe(CN)6] solution. The findings showed that current increases with increase in glucose concentration and anode displayed good electrocatalytic action with saturation current density of 27 ± 2 mA cm−2. Keywords: Bioanode, Biofuel cells, Biocompatible, Ferritin, Glucose oxidase

The presence of contaminants in potable water is a cause of worldwide concern. In particular, the presence of metals such as arsenic, lead, cadmium, mercury, chromium can affect human health. There is thus a need for advanced techniques of water decontamination. Adsorbents based on cerium dioxide (CeO2), also named ‘ceria,’ have been used to remove contaminants such as arsenic, fluoride, lead and cadmium. Ceria and composites display high surface area, controlled porosity and morphology, and abundance of functional groups. They have already found usage in many applications including optical, semiconductor and catalysis. Exploiting their attractive features for water treatment would unravel their potential. We review the potential of ceria and its composites for the removal of toxic metal ions from aqueous medium. The article discusses toxic contaminants in water and their impact on human health; the synthesis and adsorptive behavior of ceria-based materials including the role of morphology and surface area on the adsorption capacity, best fit adsorption isotherms, kinetic models, possible mechanisms, regeneration of adsorbents; and future perspectives of using metal oxides such as ceria. The focus of the report is the generation of cost-effective oxides of rare-earth metal, cerium, in their standalone and composite forms for contaminant removal.

Black phosphorus (BP) is one of the most stable allotropes among the three allotropes of phosphorus at a high temperature under a high pressure possessing new two-dimensional layered structure, which was first prepared by Bridgman in 1914. Since, the development and recent success in growing two-dimensional material family, single- or few-layered, BP has recently a vital field of interest due to their various superior properties, such as a tunable and direct/narrow band gaps, high carrier mobility, large specific surface area, photothermal property, biocompatibility, biodegradability and many interesting in-layer anisotropies and attracted considerable attention on applications in energy conversion and storage, oxygen evolution, electronics, optoelectronics, photocatalytic hydrogenation, water splitting, and thermoelectric generators, etc. Especially, there emerge contributions on electrochemical energy storage devices as supercapacitors and in batteries like lithium/sodium ion batteries. This chapter summarizes the structure and fundamental properties and few preparation methods of BP.

Polymer composites are fabricated by incorporating fillers into a polymer matrix. The intent for addition of fillers is to improve the physical, mechanical, chemical and rheological properties of the composite. This study reports on a unique polymer composite using hydrochar, synthesised by microwave-assisted hydrothermal carbonization of rice husk, as filler in polylactide matrix. The polylactide/hydrochar composites were fabricated by incorporating hydrochar in polylactide at 5%, 10%, 15% and 20 wt% by melt processing in a Haake rheomix at 170 °C. Both the neat polylactide and polylactide/hydrochar composite were characterized for mechanical, structural, thermal and rheological properties. The tensile modulus of polylactide/hydrochar composites was improved from 2.63 GPa (neat polylactide) to 3.16 GPa, 3.33 GPa, 3.54 GPa, and 4.24 GPa after blending with hydrochar at 5%, 10%, 15%, and 20%, respectively. Further, the incorporation of hydrochar had little effect on storage modulus (G′) and loss modulus (G″). The findings of this study reported that addition of hydrochar improves some characteristics of polylactide composites suggesting the potential of hydrochar as filler for polymer/hydrochar composites.

The objective of this work is to introduce a nanocomposite based bioanode for biofuel cell application. The as-prepared Kraton/MWCNTs nanocomposite was used as a current enhancer and ferritin (Frt) as a mediator between glucose oxidase (GOx) and the electrode surface. The hybrid anode achieved enzymatic oxidation of glucose by the nanocomposite reflecting an efficient energy conversion from glucose. The resulting Kraton/MWCNTs/Frt/GOx bioande exhibited good catalytic activity towards glucose oxidation along with excellent stability. The maximum current density attained by the bioanode is 1.14 mA cm-2 at the optimum glucose concentration of 60 mM. This enzymatic strategy can be employed to develop other polysaccharide or oligosaccharide fuel cells in which glucose oxidation is involved.

Turmeric/polyvinyl alcohol (PVA) thorium(IV) phosphate hybrid cation exchange nanofibers were prepared for wastewater treatment along with antimicrobial activity. The physicochemical properties of electrospun fibers like thermal stability, surface morphology and composition were evaluated by using thermogravimetric analysis/differential thermal analysis/differential thermogravimetry (TGA/DTA/DTG), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transforms infra red (FTIR), and energy dispersive X-ray (EDX) techniques. The ion exchange capacity determined by volumetric analysis was found to be 1.98 meq dry/g of ion exchanger. Antimicrobial properties of turmeric/PVA Th(IV) phosphate hybrid cation exchange electrospun fibers were validated by agar-well diffusion test (ADT) and microtitre plate assay (MPA) analyses. The presence of turmeric in polyvinyl alcohol Th(IV) phosphate hybrid cation exchange nanofibers is responsible for antimicrobial properties. The maximum zone of inhibition was found to be 22 mm for E. coli at 50 µg/ml and 21 mm for S. aureus at 100 µg/ml.