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Triple action pollutant responsive multi-layer hybrid nanocoatings of architecture PEI(PAA/ZnO-Co3O4)n were constructed through ZnO-Co3O4 binary oxide co-precipitation followed by its inclusion in multi-layer polymeric thin films using Layer-by-Layer (LbL) deposition. Characterization of the designed architecture was carried out via FTIR, XRD, UV–Vis, and Raman spectroscopic studies to evaluate the chemical nature, bonding, and crystallographic behavior of ZnO-Co3O4. Peaks of ZnO-Co3O4 were recorded at 586.38, 486.08, and 443.64 cm−1 while pronounced shifting of ZnO characteristic E2 (high) peak ~ 450 cm−1 and appearance of modes around 495, 530, 630, and 719 cm−1 indexed via Raman studies validated Co3O4 impregnation into ZnO structure. XRD patterns of ZnO-Co3O4 compared to their previously reported pristine structures also justified the formation of binary oxide as unit composite. SEM micrographs confirmed homogenous multi-layered depositions while EDX analysis confirmed their uniform elemental distribution in the unit structure. Sequential multi-layer buildup up to 48 layer pairs was monitored using ellipsometry with maximum film thickness ~ 89 nm and by UV–Vis at 376 nm. The prepared thin films exhibited significant photodegradation of methylene blue ~ 91% and Cu (II) adsorption capacity ~ 89% within first 90 min of contact, along with prominent bactericidal efficiency against E. coli within 24 h of reaction time. FAAS, ICP-OES, and UV–Vis spectroscopy analyses make these multifunctional hybrid nanocoatings promising for industrial wastewater as well as drinking water purification setups. Furthermore, protuberant recycling and regenerative capacity make these hybrid nanocoatings an eco-friendly system for hydro-remediation. [ABSTRACT FROM AUTHOR]

ABSTRACT The organic-inorganic hybrid multilayered composites are prepared using a unique combination of poly[( o-cresyl glycidyl ether)- co-formaldehyde] (CNER), amino modified montmorillonite (NH2-MMT), and polyethyleneimine (PEI). This tricomponent composite multilayer PEI(CNER/NH2-MMT/PEI) n deposited via layer -by -layer technique is based upon synergistic combination of covalent and hydrogen bonding. The growth of multilayer was monitored using UV-vis spectroscopy and ellipsometry. When subjected to optical analyses, the prepared multilayered composite films revealed profound optical transmittance ∼83%-87%. The surface morphological analysis by atomic force microscopy and scanning electron microscopy revealed uniform arrangement of organic-inorganic components with relative increase in intensity of elements (C, N, O, Si) as confirmed by X-ray photoelectron spectroscopy studies. The multilayered composites possess 1.99 GPa hardness making them potential candidate for a number of applications where mechanical strength is desired. Moreover, significant resistance against alkaline and organic solvents at minimal deterioration of circa 0.12% has also been observed for the prepared films. The epoxy clay based thin films being robust, scratch resistant, hydrophilic, chemically inert, and mechanically strong are potential candidates for advanced environmental applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46079. [ABSTRACT FROM AUTHOR]

ABSTRACT Novel electrically conductive composites were synthesized by incorporating Cu coated alumina (Cu-Al2O3) powder prepared via electroless plating technique as filler (0-21wt %) into polystyrene- b-methylmethacrylate (PS- b-PMMA) and polystyrene (PS) matrices. XRD analysis depicted maximum Cu crystallite growth (26.116 nm∼ plating time 30 min) onto Al2O3 along with a significant change in XRD patterns of composites with Cu-Al2O3 inclusion. SEM-EDX analyses exhibited uniform Cu growth onto Al2O3 and confirmed presence of Cu, Al, Pd in Cu-Al2O3, and C, O, Al, Cu, and Pd in PS- b-PMMA and PS composites. Increasing filler loadings exhibited increased electrical conductivity (5.55 × 10−5S/cm for PS- b-PMMA; 5.0 × 10−6S/cm for PS) with increased Young's modulus (1122MPa for PS- b-PMMA; 1053.9MPa for PS) and tensile strength (27.998MPa for PS- b-PMMA; 30.585MPa for PS) and decreased % elongation. TGA demonstrated increased thermal stability and DTG revealed two-step degradation in composites while DSC depicted pronounced increment in Tg of Cu-Al2O3/PS- b-PMMA with increased filler loading. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42939. [ABSTRACT FROM AUTHOR]

Block copolymers [AB]x type of aminopropyl-terminated poly(dimethylsiloxane) (NH2- PDMS) and polyamides trichlorogermyl pendant group were prepared by a solution phase one pot polycondensation method. The prepared block copolymers were assembled with polyethylene-alt- (maleic) anhydride (PEMA) as multilayered thin film assembly through covalently linked Layer by Layer (LbL) technique using dipping method. The prepared thin films had thickness in the range of 15 to 20 nm as measured on an ellipsometer. In the systems where quartz was used as substrate, film growth after each deposition was monitored through UV-Vis spectrophotometer, which substantiated the multilayer film build-up. Atomic Force Microscopic (AFM) images showed homogeneous and robust film, which were strong enough to endure the force of 400 nN. As the block copolymers are thermally stable and have the capacity to absorb water, so their prepared robust ultra-thin films can show potential of thermally resistant nano thin films, protective hydrophilic coatings in addition to separation membranes. [ABSTRACT FROM AUTHOR]

Two new metal(II) complexes formulated as [ZnI(dmae)]4·2(C7H8) 1 and CdI2(Hdmae)2 2 have been synthesized by using N,N-dimethylaminoethanol, a N,O donor ligand and characterized by melting point, elemental analysis, FT-IR spectroscopy, mass spectrometry and single crystal X-ray diffraction analysis. Complex 1 crystallizes in tetragonal I4(1)/a space group with μ2-O bridge between zinc atoms. The zinc atom is four coordinated with Zn-O 1.9315(13) and 1.9606(14) Å. The complex 2 is mononuclear with distorted octahedral geometry around the Cd(II) and contains two bidentate chelating Hdmae ligands and two iodine atoms, with Cd-O and Cd-N distances of 2.498(2) and 2.400(2) Å, respectively, and the weak O-H···I hydrogen bonds like interactions link the molecules to generate a 1D supramolecular structure. [ABSTRACT FROM AUTHOR]

• Composite membranes based on polydopamine functionalized CNT and sulfonated polysulfone were fabricated successfully. • Composite membranes exhibited efficient methanol permeability (5.68 × 10−7 cm2/s) than Nafion®117 (23.00 × 10−7 cm2/s). • PCSPS0.5 composite membrane exhibits highest proton conductivity of 0.1216S/cm is observed at 80 °C. Novel sulfonated polysulfone (SPS) based composite polymer electrolyte membranes (PEMs) filled with polydopamine modified carbon nanotubes (PD-CNTs) have been prepared using the phase inversion technique. The present study reports the development of novel and cost- efficient nanocomposite materials with excellent properties for polymer electrolyte membranes preparation. The progress is noteworthy towards the synthesis of economical organic-inorganic nanocomposites through which fuel cell related properties can be tailored. The applicability of prepared PEMs for direct methanol fuel cell (DMFC) has been investigated in terms of water uptake, methanol permeability, and proton conductivity by changing the filler content (0.5–1.0 wt. %). The carbon nanotubes were surface functionalized using polydopamine (PD) as the modifying agent. The resultant functionalized carbon nanotubes (PD-CNTs) have been incorporated into SPS polymer matrix to prepare the composite PEMs. The functional groups, structural properties, elemental analysis, morphological and topographical aspects of the resulting composite membranes were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Energy dispersive X-ray spectrometer (EDS), Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM), respectively. It was found that PD served as an outstanding glue because of its adhesive qualities, facilitated the homogeneous dispersion of CNTs into the polymer matrix, and created new proton-conducting pathways in the subsequent membranes. A detailed analysis showed that water uptake and proton-conducting properties of the engineered PEMs have been improved significantly. Composite membarne (0.5 wt. % PD-CNTs) showed 43 % increase in proton conductivity compared to the pristine SPS membrane, increasing from 0.085 S/cm for pristin to 0.1216 S/cm for the composite membrane at 80 °C. The prepared PEMs also showed an impressive 75 % decrease in methanol permeability (5.68 × 10−7 cm2/s) compared to recast Nafion®117 membarne (23.00 × 10−7 cm2/s). These results demonstrated the immense potential of polydopamine functionalized CNTs based PEMs for DMFC application. The ability of the newly synthesized membrane to retain water, and its capability to give a structural framework for maximum proton conductivity with reduced fuel crossover towards the catalyst are the significant advances from the present study. [ABSTRACT FROM AUTHOR]

In the conducted research, corncob powder was pretreated with inorganic acids and bases. The consequence of different parameters such as initial metal concentration, pH, and contact time on Zn(II) biosorption from aqueous solution was deliberated. The order of maximum Zn(II) uptake qmax (mg g-1) for different pretreated and raw corncob powder was Ba(OH)2 (128.9) > H3PO4 (124.07) > NaOH (118.737) > H2SO4 (114.8) > HCl (93.41) > Al(OH)3 (87.9) > Native (86.74). The percentage of Zn(II) removed on corncob biomass increased with increase in pH reaching a maximum at pH 5.5. Kinetics of Zn(II) biosorption described that Zn(II) sorption rate was high in first 15-30 min and equilibrium was established after 120 min. The maximum adsorption data of native and pretreated biomass was investigated using Langmuir, Freundlich equilibrium, and Pseudo-first and second-order kinetic models. It was accomplished that structural modifications onto corncob powder lead to the formation of novel biomasses with increased sorption efficiency and environmental stability for the abatement of Zn(II). [ABSTRACT FROM AUTHOR]