Help Of FTIR Research Articles

Influence of different milling media on structural, morphological and optical properties of the ZnO nanoparticles synthesized by ball milling process

ZnO nanoparticles were synthesized by ball milling process using four different milling media namely, DI water, ethanol, iso-propanol and DMF. The influence of these milling media on structural and optical properties of ZnO nanoparticles has been investigated. The X-ray diffraction and SAED analysis have been carried out to reveal structure of ZnO nanoparticles. Crystallite size and micro-strain of nanoparticles have been calculated using Scherer's formula and Williamson-Hall plots. Rietveld refinement of obtained XRD patterns has been carried out for estimation of structural and micro-structural parameters. It has been observed that structural attributes such as lattice parameters, unit cell volume, dislocation density, specific area, bond length and bond angle vary with milling media. Vibrational properties have been investigated with the help of FTIR and Raman spectroscopy. Morphological variation of particles with milling media has been revealed by FESEM and TEM investigation. Optical parameters namely, band gap energy, refractive index, extinction coefficient, dielectric constants, dielectric loss and optical conductivity have been evaluated using UV–Visible spectroscopy. The band gap values of particle synthesized in different milling media have been found in the range of 3.32–3.37 eV. Photoluminescence (PL) spectroscopy of nanoparticles has been performed to investigate the type of defects present. The study reveal that tailoring of structural and optical parameters with milling media can be done by selecting different milling media.

Synthesis and characterization of BaZrO3 nanoparticles by citrate-nitrate sol-gel auto-combustion technique: Systematic study for the formation of dense BaZrO3 ceramics

Citrate-nitrate sol-gel auto-combustion method, employing high purity (≈99.999%) precursors, is adopted for the synthesis of BaZrO3 nanoparticles. TGA-DSC, PXRD, SEM, TEM and BET techniques are used to explain (1) thermolysis of gel, (2) optimization of thermal parameters for phase pure BaZrO3 nanoparticles of unimodal size-distribution and (3) microstructural evolution at the sintering stage. Complexation of citrates with cations in the gel is confirmed with the help of FTIR and solid-state MAS-13C-NMR spectrometry. Dried gel undergoes self-sustained combustion and finally resulted in white colour ashes. Ashes on further calcination at 1000 °C-8 h resulted in BaZrO3 powder with an average crystallite size of 69.5 nm, as calculated by microstrain-domain size analysis of XRD of BaZrO3 using Rietveld refinement. The crystallite size is consistent with SEM and TEM particle size analysis. The powder is sintered without any sintering-aid to achieve the highest density (99%) ever reported, compared to similar processes reported earlier.

Polymethyl methacrylate–ovalbumin @ graphene oxide drug carrier system for high anti-proliferative cancer drug delivery

High permeable drug delivery mechanism is indispensable for the treatment of various diseases including cancer. Protein-polymeric carriers have enhanced the permeability and therapeutic of bioactive compounds. Here, polymethyl methacrylate (PMMA) as polymer and egg white protein of ovalbumin (OVA) from a natural source of quail egg was developed for the highly permeable biocompatible drug delivery system. A significant anti-cancer drug doxorubicin (DOX) was loaded on this drug delivery system. Graphene oxide (GO)-functionalized OVA–PMMA drug delivery system has increased the surface for an accumulation of drug. The drug-loading capacity and controlled release of the drug were investigated through the dialysis technique with various physiological pH environments. The effect of DOX and GO on the morphology of OVA–PMMA matrix was studied with the help of FT-IR and XRD patterns. Dynamic light scattering study gives the data about the particle size of this OVA–PMMA–GO and OVA–PMMA–GO–DOX. These data matched with the image obtained from SEM and TEM instruments. Cytotoxicity effect and cellular uptaking of DOX-loaded OVA–PMMA and OVA–PMMA–GO were investigated on gastric cancer cell line and normal cell line. All these characterizations of this study reveal that the drug is successfully loaded on this new drug carrier and controlled release was achieved.

Production and Evaluation of Antimicrobial Microcapsules with Essential Oils Using Complex Coacervation

Nowadays, the needs and requirements to avoid infections during surgical operations, require to be more imaginative than ever. The one-use textiles substrates that are used in hospitals can be, also, a way to transport the antibacterial effect around the own building. This is the main objective of this work; to use clothes and textiles surfaces as antibacterial systems using natural components. Microencapsulation has shown in several occasions the effectivity to protect and vehiculize active principles that can be used for medical treatments. In this case, essential oils have been used as antimicrobial agent, that when combined with shell polymers based on Chitosan of different molecular weight distribution and Arabic gum, allows them to act against Gram (+) and Gram (−) bacteria. The study of the efficiency of all the samples made gave a high value due to its character similar to hydrogels, while the determination of solids was higher when it was a question of samples made with a low molecular weight. The essential oil used has a very volatile character formed by more than 40 components and with the help of FT-IR and TGA it has been possible to corroborate that all its components were encapsulated. The impregnation of the different samples to the tissue was successful and allowed the antibacterial study to be carried out, which was carried out in duplicate on each sample and demonstrated that they have bacterial activity.

A comparative analysis of source based distinctly functionalized nanostructured cellulose for the adsorptive removal of toxic colorants

In order to annul the toxic dye contaminants which are being heavily discharged into the water bodies, the present study emphasizes on the fabrication of pristine and functionalized cellulose nanofibres derived from two distinct lignocellulosic biomass sources i.e. sugarcane bagasse and pine needles. Pine needles proved to be a better source than sugarcane bagasse in terms of high adsorption capacity of the adsorbents which may be due to the difference in the nanofibrillar arrangement based on source. The developed adsorbents were characterized for their structural, morphological and other physico-chemical properties with the help of FT-IR, Powder XRD, FE-SEM and EDX spectroscopic techniques. Outstanding adsorption properties of modified cellulose nanofibres were explored for the eradication of Safranin O and Methylene blue from the polluted wastewater. Structural differences based on origin resulted in the variable adsorption characteristics over functionalized adsorbents. Among all, esterified cellulose nanofibres presented best adsorption capacity for the removal of toxic colorants. Incorporation of different isotherms and kinetic models provided the deep insights of the adsorption mechanism. Functionalized cellulose nanofibres derived from two distinct lignocellulosic biomass sources for the eradication of toxic colorants from wastewater.

Antimicrobial selectivity of ruthenium, rhodium, and iridium half sandwich complexes containing phenyl hydrazone Schiff base ligands towards B. thuringiensis and P. aeruginosa bacteria

A series of new hydrazone mononuclear complexes of the type [(arene)MLCl]PF6 (M = Ru, Rh, Ir) have been synthesized in this study. All these complexes were fully characterized with the help of FT-IR, UV–Vis, mass and NMR spectroscopy. The molecular structures of representative complexes (1, 2, 7 and 8) were established by single crystal X-ray diffraction study. The molecular structures of the complexes revealed typical piano stool geometry around the metal center in which the ligand acts as NN′ donor chelating ligand. In the case of complexes (1–3), the ligand coordinates to the metal by using both the pyridine nitrogen atoms forming a six membered metallocycle whereas in complexes (4–9) one hydrazone nitrogen atom and one pyridine nitrogen atom coordinates to the metal ion forming a five membered metallocycle. These compounds were evaluated for their in vitro antibacterial activity by agar well diffusion method against two Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, and two Gram-positive bacteria Staphylococcus aureus, Bacillus thuringiensis. Results show that all the complexes inhibit the growth of bacteria.

Lactic acid oligomer (OLLA) grafted gum arabic based green adhesive for structural applications

L-Lactic acid (LA)-grafted-gum arabic (GA) graft copolymer [OLLA-g-GA] was prepared by using microwave heating in which the hydrophilic GA was grafted with insitu grown lactic acid oligomer. The grafting at OH and NH groups in GA backbone with oligo-(l-lactic acid) (OLLA) chains proved with the help of FTIR and NMR analyses. The grafted GA was dispersed uniformly in OLLA due to the formation of amphiphile GA backbone grafted with OLLA chains, which is supported by XRD, SEM and TEM analyses. This synthesized OLLA-g-GA graft copolymer showed adhesive characteristics with various substrates such as glass and granite. The single lap shear joint of two glass and two granite substrates were fabricated and the adhesive properties of these laminated substrates were tested using Universal Testing Machine. The synthesized biobased adhesive showed excellent shear strength with respect to the present biobased adhesives and substrate failure was observed at optimized conditions during the shear test.

Biopolymeric nanogel derived from functionalized glycogen towards targeted delivery of 5-fluorouracil

We report the synthesis, characterization and application of a novel biocompatible nanogel (n-Gly/pHEMA) synthesized from glycogen and 2-hydroxyethyl methacrylate using ethylene glycol dimethacrylate crosslinker. Here mesoporous silica has been used as template. The structure of the nanogel has been investigated with the help of FTIR, 1H NMR and 13C NMR spectroscopy. The FESEM, HR-TEM and DLS analyses exhibit that the size of the nanogel is in the range of 10–50 nm. Thermal degradation kinetics suggests the higher stability of the n-Gly/pHEMA nanogel after crosslinking. The gel strength has been assessed by measurement of rheological parameters. The native nanogel shows a good compatibility with MG-63 cell lines. The n-Gly/pHEMA nanogel can effectively load 5-fluorouracil (5-FU) with encapsulation efficiency of ∼60% after 48 h. The intercellular release experiment demonstrates that 5-FU loaded nanogel can efficiently kill the MG-63 cancer cells. In vitro release profile demonstrates controlled release behaviour with higher 5-FU release rate at pH 5.5 compared to pH 7.4.

2,2′-bipyridine-functionalized single-walled carbon nanotubes: The formation of transition metal complexes and their charge transfer effects

There is presently a great interest in the development of versatile nanohybrid systems that are based on the covalent functionalization of carbon nanotubes. Covalent functionalization of the single walled carbon nanotubes (SWCNTs) enhances their processability and functionality, allowing them to be further used in different applications. However, at the same time this leads to a disturbance of the nanotube π-network, thus reducing its intrinsically distinct physical and chemical properties of nanotubes. In the optimal situation, covalently functionalized SWCNT nanohybrid materials could be formed in a way where both of these wanted properties would exist; Good processability and the electronic properties nanotubes had before the functionalization. In this work, we describe the formation of nanohybrid materials by covalently grafting bipyridyl ligands directly onto the sidewall of the SWCNT. This is followed by addition of several different transition metals to form organometallic complexes. The systems we describe here does not utilize linker molecules between the ligands and the nanotubes allowing a better electronic communication between them. The covalent addition of the ligand onto the sidewall first causes p-type doping which is reversed to n-type doping after the addition of a transition metal. This technique offers a possibility to tune the electronic properties through reversing doping in charge transport between substrates and SWCNT. All new nanotube hybrids were fully characterized with the help of FTIR, XPS, Raman spectroscopy and HRTEM.

Hydrous ZrO2 decorated polyaniline nanofibres: Synthesis, characterization and application as an efficient adsorbent for water defluoridation

A new hybrid material comprising hydrous zirconium oxide (HZrO2) supported onto polyaniline (PANI) nanofibres (HZrO2@PANI NFs) was prepared via the precipitation of HZrO2 onto as-synthesized PANI NFs and tested for its defluoridation capabilities. The developed adsorbent (HZrO2@PANI NFs) was fully characterized by FTIR, BET, XRD, SEM-EDX, TEM-(S)TEM, XPS, and zeta potential measurements. HZrO2@PANI NFs achieved 2-fold BET surface area ∼86.64 m2/gas compared to PANI NFs ∼44.72 m2/g, implying that the incorporation of HZrO2 onto the PANI nanofibres enhanced the available surface area for effective fluoride adsorption. Moreover, HZrO2@PANI NFs was found to be effective over a wide pH range (3–9) as designated by its high pHpzc ∼9.8. The adsorption kinetics obeyed the pseudo-second-order model well with equilibrium attainment in 30min. Adsorption isotherm was best described by the Langmuir model and the maximum adsorption capacities obtained were 83.23 and 28.77mg/g at pH 3 and 6.5, respectively, which is superior to most ZrO2 based adsorbents reported in the literature and better than that of native PANI. Furthermore, the developed adsorbent manifested quite a selective fluoride uptake at pH 3 as compared to pH 6.5±0.1 wherein significant chemical affinity competition was presented by phosphate ions followed by bicarbonate and sulfate. The recyclability of HZrO2@PANI NFs for four cycles and its applicability to fluoride spiked ground water has also been demonstrated. The adsorption mechanism was interpreted with the help of FTIR, XPS and Zeta potential analysis and the results revealed the involvement of both anion exchange and electrostatic attraction in the adsorption of F− ions. Thus, a new efficient adsorbent with reasonably high adsorption capacity and superior pH tolerance has been developed for fluoride removal.

Exploration of complexes of 18-crown-6 with three similarly substituted imidazolium, pyridinium and pyrrolidinium ionic liquids

Supramolecular host-guest complexation with excellent comparison among three similarly substituted ionic liquids, namely, 1-butyl-3-methylimidazolium chloride, 1-butyl-4-methylpyridinium chloride and 1-butyl-1-methylpyrrolidinium chloride have been investigated with 18-crown-6 in acetonitrile medium by conductivity in a range of temperature to elucidate the stoichiometry of the complexes. The programmed mathematical study with the help of conductivity data provides association constants for the complexes, by which the thermodynamic properties have been evaluated for improved understanding about complexation. The molecular interactions have been explained and critically discussed with the help of FT-IR and 1H NMR spectroscopic studies, which illustrate H-bond and ion-dipolar attractions primarily exist in complexation.

Bauhinia tomentosa Leaves Extract as Green Corrosion Inhibitor for Mild Steel in 1M HCl Medium

Bauhinia tomentosa leaves extract (BTLE) as a corrosion inhibitor in 1M HCl was investigated by using weight-loss method and electrochemical techniques. The inhibition efficiency of BTLE was found to increase with increasing concentration. The effect of temperature on the corrosion inhibition of mild steel in the temperature range of 308–333 K was studied. Polarization measurements revealed that the BTLE acted as a mixed-type inhibitor. Nyquist plots showed that on increasing the BTLE concentration, the charge-transfer resistance increased and double-layer capacitance decreased. The adsorption of BTLE on mild steel obeyed the Langmuir adsorption isotherm. The maximum inhibition efficiency was found (93.47% in HCl) at 308 K in the presence of 700 ppm of BTLE. Mechanism of corrosion inhibition of BTLE on mild steel is explored with the help of FT-IR, UV, SEM and AFM techniques.

Synthesis of functionalized biomaterials and its application in the efficient remediation of aquatic environment contaminated with Cr(VI)

The aim of this study is to synthesize the three different hybrid materials precursor to natural biopolymer chitosan. The silanes viz., 3-mercaptopropyl trimethoxysilane, trimethoxy(octyl) silane and 3-aminopropyl triethoxysilane were grafted with the chitosan network and were named as CHMS, CHTS and CHAS, respectively. The materials were characterized by the FT-IR spectrometry, SEM–EDX and XPS analyses. These solids were then employed in the efficient removal of Cr(VI) from aqueous solutions using batch and column reactor operations. The functionalized biomaterials possessed extremely high percent removal of Cr(VI) compared to bare chitosan at wide pH range i.e., pH ∼3.0 to 8.0. A fast uptake of Cr(VI) was occurred and high percentage removal was obtained at wide range of Cr(VI) initial concentrations (7.7–100.58mg/L). The equilibrium state sorption data were utilized for the Langmuir and Freundlich adsorption isotherm studies. Similarly, an increase in background electrolyte concentrations from 0.0001 to 0.05mol/L NaNO3 was assessed for the uptake of Cr(VI) by these hybrid materials. Relatively a fast uptake of Cr(VI) by these hybrid materials were obtained and further the time dependence data were fitted well to the pseudo-second-order and fractal-like pseudo-second-order kinetic models rather a pseudo-first-order kinetic model. Furthermore, a detailed sorption mechanism was included with the help of FT-IR, TOC and XPS analyses. In addition, CHMS and CHTS were used for dynamic studies under column reactor operations. The breakthrough curves were then used for the non-linear fitting of the Thomas equation and the loading capacity of the column for Cr(VI) were estimated.

Combustion synthesis of Sr2B2O5:Tb3+ green emitting phosphor for solid state lighting

Terbium doped Sr2B2O5 green phosphor was synthesized by combustion synthesis method at about 550°C. Further, analyzed by XRD technique and XRD pattern of prepared phosphor is well match with standard JCPDs file. The morphology and structure of the phosphor were characterized by scanning electron microscopy. The chromatic coordinates estimated from emission spectra shown by CIE chromatic diagram and values observed are Cx=0.263, Cy=0.723. The vibrational characteristics were studied with the help of FTIR. The excitation and emission spectra specify that the prepared phosphor can be effectively excited by 353nm and reveal bright green emission centered at 545nm consequent to the D→F transition of Tb3+ ion. From the obtained results it is concluded that present phosphor may be efficient photoluminescent materials for solid-state lighting and energy saving applications.

Mechanistic Investigation of Osmium(VIII) Catalyzed Oxidation of Glutamic Acid With Sodium Salt of N-Chloro 4-Methylbenzenesulfonamide in Aqueous Media: A Practical Approach

L-glutamic acid is used in the production of monosodium glutamate spices and other biochemical reagents. Its oxidation kinetics and a detailed mechanistic interaction of Os(VIII) catalyzed Glue-CAT reaction in alkaline medium have been investigated at different temperatures. It has been studied spectrophotometrically as a basic experimental approach for this study. All variables affecting the development of the color were investigated and the conditions were optimized. The effect of Glue, CAT, Os(VIII), and OH concentration on the rate of reaction has been studied. The reactions follow identical kinetics for all It is a first order reaction in both Glue and CAT, but fractional order in alkali and Os(VIII). Increasing ionic strength dielectric constant of the medium had no significant effect on the rate. The effects of added products like halide ions and toluene-p-sulfonamide have also been investigated. A mechanism involving the formation of a complex between Glue-CAT-Os(VIII) has been proposed. The stoichiometry of the reaction is found to be 1:1. The main products of Glue were identified with the help of FTIR and TLC. The reaction constants involved in the mechanism are explained. There is a good agreement between the observed and calculated rate constants under different experimental conditions. Investigations at different temperatures allowed the determination of the activation parameters with respect to the slow step of the proposed mechanism. The proposed methods were successfully applied for the high yield of the products and short reaction times. It is also an inexpensive, simple, and smooth method.

Synthesis and characterization of linear dendritic homo and copolymers acrylated behera amine

A co-polymerizable dendron of first generation synthesized from behera amine was homopolymerized and copolymerized with commercial monomers such as styrene, methyl methacrylate, and N-vinyl pyrrolidone. Characterization of the co-polymers was performed and it was found with the help of FT-IR and proton and carbon NMR that copolymerizable dendron, ACTES (ACrylated TriESter, first-generation dendron of acrylated behera amine) was incorporated in the co-polymer chains. Besides, the reactivity ratio pairs of the ACTES monomer with both styrene and n-vinyl pyrrolidone were determined. The reactivity ratio pair for ACTES and MMA could not be determined by neither gravimetrically nor with NMR. After experiments and calculations, the reactivity ratio pair for styrene and ACTES was found to be rst = 0.27 and rac = 0.44 and for NVP and ACTES rnvp = 0.36 and rac = 1.01. By utilization of the reactivity ratio of ACTES, “Q” and “e” values were determined in order to be able to draw some conclusions about the reactivity behavior during copolymerizations. “Q” = 1.152 and “e” = 0.66 were found with respect to styrene as reference. These values indicates the steric effect of ACTES was more dominant in copolymerizations.

Synthesis of ZnSnO3 nanocubes and thin film fabrication of (ZnSnO3/PMMA) composite through electrospray deposition

A composite of zinc stannate (ZnSnO3) nanocubes and poly(methyl methacrylate) (PMMA) has been prepared and deposited on a flexible substrate polyethylene terephthalate (PET) through electrospray deposition (ESD). This fabrication technique has been found very effective for deposition of this composite as thin film. ZnSnO3 is an inorganic biocompatible and piezoelectric material while PMMA is a transparent and durable organic polymer material. ZnSnO3 naocubes have been synthesized via an aqueous solution method and ZnSnO3/PMMA composite has been deposited as thin film on PET through ESD. The average layer thickness of the as deposited ZnSnO3/PMMA composite film on PET was found to be 149 nm. Morphological and structural characterization of ZnSnO3 nanocubes through FESEM and XRD showed its size uniformity and crystalline nature. The size of the ZnSnO3 nanocubes was estimated by FESEM analysis which was around 50–70 nm. The chemical composition has been investigated with the help of FTIR and Raman spectroscopy. The optical characterization of as deposited ZnSnO3/PMMA composite film through UV/Vis spectroscopy showed an average transmittance of around 92 % and electrical characterization exhibited resistivity of approximately 50 × 105 Ω cm. This dielectric nature of ZnSnO3/PMMA composite film indicates that this composite material can be employed as dielectric layer in printed electronics.

Study of dc Electrical Conductivity, Magnetic Susceptibility and Thermal Behavior of Pyrrole Aniline Copolymer

Chemical copolymerization of pyrrole and aniline has been carried out by taking the monomers in equimolar proportion. The structural analysis of the copolymer was done with the help of FTIR, WAXD and SEM techniques, the results confirm the formation of new material involving both pyrrole and aniline units. The dc electrical conductivity of the copolymer has been recorded up to 673k using two probe method. The log σ Vs 1/T plot shows the transition of the sample from metallic to semi conducting behavior and vice versa, at a particular temperature. The magnetic susceptibility was recorded at magnetic field of 0.1KG in the temperature range 313-507 K by using Guoy's method. The Thermal behavior of the copolymer was studied using DTA-TGA revealing variation in the Tg of copolymer when compared to homopolymers.

Photo‐induced graft copolymerization of acrylonitrile onto sodium salt of partially carboxymethylated guar gum

ABSTRACTPhoto‐induced graft copolymerization of acrylonitrile (AN) onto sodium salt of partially carboxymethylated guar gum (Na‐PCMGG, = 0.291) was carried out in an aqueous medium using ceric ammonium nitrate (CAN) as photo‐initiator to synthesize a novel graft copolymer, Na‐PCMGG‐g‐PAN, which may find potential application as a superabsorbent hydrogel. Studying the influence of concentrations of photo‐initiator (CAN), nitric acid, monomer (AN) as well as reaction time, temperature, and amount of substrate on the grafting yields, the reaction conditions for optimum grafting were evaluated. Maximum values of the grafting yields achieved were %G = 285.77 and %GE = 70.76 at optimized conditions. The proposed kinetic scheme could explain very well the experimental results. The influence of different kind of acids on the grafting yields was also studied. Grafting process was confirmed with the help of FTIR, thermal (TGA/DSC), and SEM techniques. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41371.

Polyaniline Binder for Functionalized Acetylene Black: A Hybrid Material for Supercapacitor

Polyaniline-doped with functionalyzed acetylene black material has been successfully synthesized and used as an electrode material in supercapacitor, wherein, this material contributes both pseudocapacitative (PC) and electrical double layer capacitative (EDLC) behaviour. Functionalization of acetylene black (AB) has been carried out and used as dopant for THF soluble polyaniline base (PANI) to prepare PANI-functionalized acetylene black (PANI-FAB). Formation of FAB and PANI-FAB was confirmed with the help of FT-IR and XPS study. Functionalization of AB results in agglomerated FAB and doping with PANI results in agglomerated fibrous PANI-FAB, as compared to fibrous AB. High thermal stability of AB decreases on functionalization and again slightly increases for PANI-FAB. Functionalization of AB also results good bonding effect with PANI, where PANI acts as both PC and binder, instead of the higher amounts of binder (PVdF > 30 wt%) that are normally needed to hold AB. Electrochemical studies of FAB and PANI-FAB materials were carried out by cyclic voltammetric and electrochemical impedance spectroscopic methods. PANI-FAB supercapacitor cell shows capacitance of 132 Fg1 for 0.3 Ag1 current density with very low charge-transfer resistance and low time constant.