NLO Susceptibility Research Articles

Investigation on growth, structural, mechanical, linear and nonlinear optical properties of DiLithium Fumarate TetraHydrate single crystal

In this work reports on the growth and characterization of semiorganic NLO single crystal of DiLithium Fumarate TetraHydrate (DLFTH) using a slow evaporation technique. The crystal structure was an orthorhombic crystal system with the centrosymmetric space group Pbcn, as demonstrated by single crystal X-ray diffraction (SCXRD) investigations. The UV–Vis-NIR spectrum is used to derive optical parameters, such as the lower cut off wavelength (277 nm) and optical energy band gap Eg = 4.98 eV. DLFTH crystals belongs to hard material category using Vickers microhardness test. From NLO studies, the nonlinear optical parameters were studied, such as the nonlinear refractive index (n2), absorption coefficient (β) and third order NLO susceptibility (χ3). The crystal has the properties of saturable absorption and self-defocusing nature. Third order NLO susceptibility (χ3) were found to be 4.14384 × 10-10esu. The higher χ3 number is due to the presence of hydrogen bonds between C-H-O and O-H-O atoms. Therefore, we confirm that it’s applicability for optical device applications.

Material synthesis, crystal structure, Hirshfeld surface and physicochemical characteristics Novel Stilbazolium crystal of 4-(2-(3-ethoxy-4-hydroxy-phenyl)-vinyl)-1-methyl pyridinium iodide (MEMPI) single crystal for NLO activity

In this study, a novel cation donor group 3-ethoxy-4-hydroxy benzaldehyde has been incorporated in the Stilbazolium cation with iodide anion to generate a new NLO activity of a single crystal of 4-(2-(3-ethoxy-4-hydroxy-phenyl)-vinyl)-1-methyl pyridinium iodide (MEMPI). The MEMPI crystal was effectively formed via the solvent evaporation technique. The structure and hydrogen bond interactions found in the molecule were determined by employing single-crystal X-ray diffraction. The compound crystallizes in the space group P21/c and monoclinic crystal pattern. The crystal structures are stabilized via intramolecular, intermolecular hydrogen bond interactions, C‒H···π, cation‒π, anion‒π, π···π stacking and lone pair-π interaction. In addition, a variety of O‒H···O, O‒H···I and C‒H···O interactions are also responsible for crystal packing. The 3D Hirshfeld surface and 2D fingerprint plots were used to examine the nature of intermolecular interaction. The 2D fingerprint maps indicate that the interactions between H···H contribute to 48.9 % of the total crystal stability. The newly synthesized material was characterized by 1H NMR and 13C NMR. In addition, the vibrational study of the synthesized molecule was performed using FTIR analysis. The grown crystal in linear optical characteristics were examined via a UV–Visible-NIR study. The photoluminescence (PL) activity of a MEMPI was studied with respect to the visible area and green colour emission was observed at 536 nm. The estimated CIE coordinates on the RGB colour gamut show the MEMPI crystal's ability to emit green light. The chemical etching approach was used to analyse the etch pit density and the growth habitat of the MEMPI crystal. The closed and open aperture Z-scan tests were carried out to determine the nature of third-order NLO susceptibility of the MEMPI crystal.

Crystal Growth, Optical, Thermal, DFT and Z‐Scan Studies of Imidazolium Hydrogen Fumarate Crystal for Nonlinear Optical Applications

AbstractOrganic imidazolium hydrogen fumarate (IHF) crystals are grown using the slow evaporation method. The IHF has triclinic crystal structure. The 1H NMR spectrum has five chemical shifts for the IHF crystal. The band at 3155 cm−1 in IR occurs due to the presence of O─H stretching vibration of the IHF molecule. The bandgap value of the IHF crystal is determined to be 4.6 eV. The intense violet emission band is noted at 361 nm. The IHF crystal has thermal stability value of 179 °C. Hirshfeld surface is used to find out the different intermolecular interactions of the IHF crystal. The HOMO–LUMO energy gap is determined to be 4.70 eV. The hydrogen atoms have positive potential in the MEP analysis. The high stabilization energy of 56.81 kcal mol−1 is noticed for π*(C1─N7) → π*(C2─C3) interaction. The third‐order NLO susceptibility (χ(3)) of the IHF is 2.08934 × 10−9 esu.

Synthesis, crystal structure, spectroscopic and computational studies of NLO active 2-methylimdazolium 4-nitrobenzoic acid single crystal

In this report, we have presented the theoretical and experimental investigation of 2-Methylimdazolium 4-Nitrobenzoic Acid (2MI4NB) – an organic crystal. The good quality 2MI4NB single crystal was grown by slow evaporation technique. Both single and powder X-ray diffraction (XRD) analysis confirmed that the grown crystal structure is Triclinic with the P1 space group. The vibrational modes present in the chemical were validated through Fourier transform infrared (FT-IR) spectrum investigations. Density functional theory (DFT), a quantum chemical approach, has emerged as a potential or an effective tool for studying molecular structure and NLO properties and is being used frequently in applications involving NLO systems. HOMO-LUMO analysis and reactivity parameters were calculated. Molecular Electrostatic Potential (MEP), Natural Bond Orbital (NBO) analysis and first order hyper polarizability were studied by B3LYP theoretical level with 6-311++G(d,p) basic set. In addition, the Mulliken Atomic Charge was calculated with the same basic set. The thermal properties of the 2MI4NB crystal was analysed by TG-DTA studies. It shows that the two endothermic peaks were observed. The optical absorption spectrum shows that there is no absorption in the region of 430–1200 nm. The Z-scan analysis gives the third order NLO properties like refractive index and third-order NLO susceptibility of 2MI4NB crystals.

Investigations on structural, dielectric, and third-order nonlinear optical studies of Ni0.5Zn0.5Fe2O4 nanoparticles by microwave combustion method with different fuels (glycine, urea and citric acid)

In this article, Ni0.5Zn0.5Fe2O4 nanoparticles (NPs) were synthesized via microwave-assisted combustion method. XRD investigation indicates the cubic spinel structure. At ambient temperature, the dielectric constant and loss were determined by modulating the applied frequency (50 Hz to 200 kHz). The calculated third-order NLO susceptibility (χ(3)) was found for glycine (2.385 × 10-6esu), urea (0.9696 × 10-6esu) and citric acid (2.755 × 10-6esu). However, this work reveals that synthesized NPs have high convenience for optoelectronic, optical switching, and limiting applications.

Exploring linear and nonlinear optical behaviour of morpholine p-nitrophenol crystal: Computational and experimental analysis

Optically good quality morpholine p-nitrophenol (MPN) crystal was effectively grown from a slow evaporation technique. Unit cell parameters of MPN were estimated by single crystal X-ray diffraction and it crystallizes in the P21/c space group. The existence of several functional groups in MPN is established by FTIR analysis. UV–vis-NIR spectroscopy inspected the lower cut-off wavelength and band gap energy of MPN. A fluorescence spectral analysis of MPN was carried out. Experimental and computational calculations of nonlinear optical activity have been studied. The second harmonic generation of MPN is 1.9 times greater than the reference KDP material. Using the Z-scan approach, the grown crystal's third-order NLO susceptibility (χ3) was determined. The laser damage threshold of MPN crystal is studied and it is estimated as 5.12 GW/cm2. The highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and molecular tying-up explorations were executed. Ground state enhanced geometry and molecular electrostatic potential (MEP) were analysed.

Substantial effect of Cr doping on the third-order nonlinear optical properties of ZnO nanostructures

Here in, the present work we report the influence of Cr doping on the nonlinear properties of hydrothermally prepared ZnO nanoparticles. Structure has been confirmed from XRD analysis and exhibit a hexagonal wurtzite structure. Observed peak shift and decrease in crystallite size observed from XRD analysis confirms the successful Cr doping. FE-SEM images show distorted rod-like morphology and the doping percentages are confirmed from the EDAX spectra. The XPS spectrum confirms the existence of oxygen vacancies, which validates the existence of divalent oxidation states of zinc and the trivalent state of chromium. The calculated bandgap values validate thatZn0.98Cr0.02O nanoparticles exhibit the lowest bandgap energy due to the presence of optically active sub-levels within the bandgap region. Variation in peak intensity was observed from the Raman spectra, which validates the addition of Cr into lattice sites of ZnO. Under continuous wave (CW) laser regime, the Z-scan method was used to determine the third order nonlinearity and demonstrate, Zn0.96Cr0.04O nanoparticle show a combined effect of saturable absorption (SA) and reverse saturation absorption (RSA) under open aperture measurements with an increase in nonlinear absorption coefficient (βeff), and third-order NLO susceptibility (χ(3)) values on increasing Cr3+ doping concentration.

Linear and third-order nonlinear optical properties of spray pyrolysis deposited Mn doped ZnS nanostructured thin films for optoelectronic device applications

The undoped and 10 wt% of Mn-doped ZnS thin films have been deposited on a glass substrate at 350 °C using the spray pyrolysis technique. The structural, morphological, linear and third-order nonlinear (NLO) properties are reported. The XRD pattern showed that ZnS thin film has a cubic structure. The FESEM images show the uniformity of coating and improvement in the smoothness of the surface after adding the Mn dopant to the ZnS lattice. Using a UV–VIS spectrophotometer the optical energy band gap of ZnS film was found to be 3.71 eV and for 10 wt% of Mn-ZnS is 3.76 eV. By the method of Z-scan, the materials demonstrated good nonlinear absorption (NLA), nonlinear refraction (NLR) and third-order NLO susceptibilities. The magnitude of third-order NLO susceptibilities (χ)(3) 10-6 esu, NLA coefficient (β) 10-5 mW−1 and nonlinear refraction (n2) 10-8 cm2/W. The positive findings of NLO of Mn: ZnS thin film as optoelectronic devices and optical switching applications.

Synthesis–dependent morphological, structural and photophysical properties of semicrystalline KNbO3:SiO2 hybrid silicates

Polycrystalline ceramics of KNbO3 (KNO) were prepared via sol–gel (by acrylamide polymerization), hydrothermal, and solid–state chemistry reactions. Pure orthorhombic perovskite phases crystallized in the Cm2m (38) space group were attained in all cases. Average crystallite sizes ranging 33–44 ​nm and grain structures varying from 350 to 580 ​nm were obtained depending on the implemented synthetic route. Prepared KNO compounds were embedded in porous a–SiO2 sonogel networks at different dopant rates to conform semicrystalline KNbO3:SiO2 hybrid silicates. Results evidence a clear dependence of the structural and optoelectronic properties of the composite glasses on the employed synthesis methodology. The massive porosity of the sonogel matrix and related defective bonding environment promoted strong intermolecular host–guest interactions influencing the electronic states, structural phase transitions, and Raman and luminescent features of the hybrid glasses via surface–assisted mechanisms and chemical charge–transfers. NLO/SHG activity was observed in all hybrid sonogels (HSG) due to the ferroelectric nature of KNO and the average macroscopic crystallite alignment attained along the polycondensation stage of the solid–solutions; where bulk NLO susceptibilities up to 9.10×10−11 ​esu and molecular hyperpolarizabilities in the 10−23 ​esu range, were estimated. Depending on the synthetic method and hybridized in–gap levels, bandgap energy narrowing was observed for the KNO/HSG systems, showing Eg values ranging 2.45–3.30 eV. A synergistic study comprising morphological, structural, spectroscopic, and quadratic NLO/SHG characterizations was performed to explore these novel composites’ structural and photophysical properties for Pb–free ferroelectric/optoelectronic composite applications.

Crystal growth and physicochemical characterization of urea doped 4-methoxyaniline (U-4MOA) single crystals for NLO and antimicrobial applications

The single crystals of 4-methoxyaniline doped with urea (U-4MOA) were grown by slow evaporation method. The crystal structure of the U-4MOA was determined to be orthorombic using single-crystal X-ray diffraction (SXRD) investigation. The existence of functional groups was substantiated by FT-IR spectrum. The percentage of elements contained in the grown crystal was estimated using EDAX analysis. The surface studies by scanning electron microscopy reveals the formation of interlaced pattern in U-4MOA crystal. Thermal properties of U-4MOA were determined by TGA and DTA methods and it melts at 69°C. The UV-visible study discloses the transparency of the grown crystal throughout visible region. Fluorescence spectrum of U-4MOA shows an emission band at 663 nm. The mechanical properties of U-4MOA were determined from Vickers's hardness testing. The electrical properties of the U-4MOA crystal were investigated using impedance analysis. SHG efficiency of U-4MOA was spotted to be 1.71 times greater than KDP. Z-scan analysis revealed that U-4MOA has a large third order NLO susceptibility. The antimicrobial activity of the grown U-4MOA sample was performed against certain pathogens for medicament applications. In addition, the crystal packing and intermolecular interconnection were determined using Hirshfeld surface analysis.

Corona poling of PMMA based thin films doped by oxy and carboxy derivatives of [2,2]paracyclophane

Results of field corona poling experiments on thin film of polymethyl methacrylate (PMMA) polymer doped with molecules of substituted [2,2]paracyclophane are presented. Namely hydroxy/metoxy and formyl/ketone derivatives of [2,2]paracyclophane with different mutual orientation of the substituents were studied. The maximum value of second order NLO susceptibility χ(2)(−2ω;ω,ω) of 72.2 ± 7.2 p.m./V measured at 1064.2 nm fundamental wavelength was observed for phenyl substituted molecule. X-Ray structure and absorption spectroscopy data as well as quantum chemical calculations were engaged for the discussion of the values obtained.

Growth, Structural, Spectral, Thermal, Optical, Second and Third Order Nonlinear Optical Properties of Imidazolium Hydrogen Squarate (IHS) Single Crystal

Abstract: Imidazolium hydrogen squarate (IHS) crystal has been grown by slow evaporation solution growth technique at room temperature. The lattice parameters of grown crystal were determined using single crystal X-ray diffraction data and compared with powder XRD. Single crystal XRD shows that the crystal crystallizes in monoclinic system with noncentrosymmetric space group Pc. The crystallinity of the grown crystal was confirmed by X-ray powder diffraction analysis. FT-IR and FT-RAMAN analyses qualitatively confirm the various functional groups present in the grown crystal. The 1H and 13C NMR spectra were recorded to establish the molecular structure. Thermal properties of title crystal were studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The UV-Vis-NIR transmission spectrum was recorded to find the band width of optical transmittance window and the lower cutoff wavelength. The optical band gap value of the material is evaluated to be 5.6 eV. The second harmonic generation efficiency was calculated by the Kurtz and Perry powder method using a Q-switched mode locked Nd: YAG laser emitting 1064 nm laser as source. Finally, Z-scan technique was employed to determine the nonlinear refractive index, nonlinear absorption coefficient and third-order NLO susceptibility to find suitability of the grown crystal in photonics and optoelectronics applications. Keywords: Single crystal; Powder XRD; thermal analysis; SHG; Z-scan studies

Concentration effects on optical properties, DFT, crystal characterization and α-glucosidase activity studies: Novel Zn(II) complex

A novel Zn(II) complex of 6-ClpicH and picH was synthesized and its structure was determined by XRD technique. The detailed experimental optical susceptibility and band gap, refractive index, linear polarizability, optical and electrical conductivity parameters in various concentrations were investigated by means of the UV–Vis spectroscopic data. The optical band gap, refractive index (n), linear optical susceptibility (χ(1)), third-order nonlinear optical susceptibility (χ(3)), second- and third-order nonlinear optical (β and γ) parameters were examined by using DFT/M06-L and ωB97XD/6–311++G(d,p) levels. The IC50 value of Zn(II) complex against α-glucosidase was also obtained at 0.44 mM. The experimental band gap of the Zn(II) complex at 13, 33, 44 and 94 µM concentrations in ethanol were found to be 4.38, 4.37, 4.35 and 4.28 eV, respectively. The third-order NLO susceptibility χ(3) parameter at 94 µM concentration corresponding to the photon energies of 4.6 and 5.7 eV in the UV–Vis region were observed at 206.6 × 10-13 and 294.3 × 10-13 esu, respectively. Besides, the theoretical χ(3) values were obtained at 50.58 × 10−13 and 20.37 × 10−13 esu by using M06-L level. These results indicate that Zn(II) complex could be an effective third-order NLO candidate material. In brief, the detailed theoretical and experimental structural, spectral and optical properties of the Zn(II) complex were presented comparatively.

Exploring Unusual Electrochemistry and Nlo Properties of Highly Electron-Deficient β-Functionalized Porphyrins

A series of β-tetracyanobutadiene(TCBD) appended porphyrins, M-TCBDP (M = 2H (2), Cu(II) (3), Ni(II) (4), Co(II) (5), Zn(II) (6)) were synthesized and characterized by various spectroscopic and electrochemical techniques. These porphyrins exhibit mutiredox process. Particularly, the unusual reduction potential in the range of -0.06 to -0.10 V is the consequence of TCBD group present at the β-position. The existence of enhanced polarization and intramolecular charge transfer in the absorption spectra are held responsible for nonlinear optical responses exhibited by the M-TCBD series as compared to the precursor (H2-PE2 (1)). Femtosecond Z-Scan experiments were performed to elucidate the third-order nonlinear optical properties and the temporal response of these porphyrin molecules are investigated using pump-probe spectroscopy to study the excited state transient absorption dynamics. Z-scan measurement reveals that Co-TCBD (5) exhibits better nonlinear optical response as compared to free base porphyrins. Two-photon absorption coefficient (β) and the imaginary part of third-order NLO susceptibility (χ(3) ) were procured from open aperture experiment whereas close aperture experiment delivers magnitude and sign of nonlinear optical refractive index (η2) and the real part of χ(3) . The excellent optical limiting threshold of synthesized porphyrins makes them adorable material for laser protection.

Crystal growth, optical, thermal, mechanical and third-order nonlinear optical properties of L-lysine hydrochloride-doped sulphamic acid single crystals for optical applications

L-lysine hydrochloride-doped sulphamic acid (SA) crystals have been grown by slow evaporation technique. X-ray diffraction experiments confirmed the orthorhombic structure of SA crystal. The doped crystals have high transmission than the pure SA crystal. TG and DTA studies exhibit the title crystals are thermal stability up to 212 °C (pure), 210 °C (1 mol%) and 207 °C (2 mol%). The enhancement of the hardness value in the doped crystal was confirmed by the hardness test. The etch pit density was measured using chemical etching study. The photosensitivity of the grown crystals is 0.10 (pure), 0.36 (1 mol%) and 0.72 (2 mol%). The laser damage threshold (LDT) analyses show that the L-lysine hydrochloride-doped SA crystals have more LDT value than the pure SA crystal. Third-order NLO susceptibility was found to be 5.004, 5.864 and 6.050 × 10–10 esu for pure and L-lysine hydrochloride-doped (1 and 2 mol %) SA crystals, respectively.

Crystal structure, linear and nonlinear optical properties of three thiophenyl chalcone derivatives: A combined experimental and computational study

Abstract Three thiophenyl chalcone derivatives, (E)-1-(5-bromo-2-thienyl)-3-(4-bromophenyl)prop-2-en-1-one (B5B2SC), (E)-1-(5-bromo-2-thienyl)-3-(3-chlorophenyl)prop-2-en-1-one (3C5B2SC), and (E)-1-(5-bromo-2-thienyl)-3-(2-methoxyphenyl)prop-2-en-1-one (2M5B2SC), were successfully synthesized and crystallized. The structures were confirmed by experimental and theoretical FTIR and 1H NMR spectra. The crystal structures were determined by single-crystal XRD method. The B5B2SC, 3C5B2SC and 2M5B2SC crystallize in the monoclinic space groups P 21/c (centrosymmetric), P 2 (non-centrosymmetric) and triclinic space group P 1 ‾ (centrosymmetric), respectively. All these structures adopt trans configuration with respect to C6═C7 double bond. The chalcones have high thermal stability, a wide transparency in the visible region and small optical band gaps. The 3C5B2SC exhibits powder second-harmonic generation (SHG) intensity of about 1.7 times higher than Urea. From continuous wave (CW) laser (532 nm) Z-scan experimental data analyses, the third-order NLO parameters such as nonlinear absorption coefficient (β = ~10−4 cm/W), nonlinear refractive index (n2= ~10−9 cm2/W), third-order NLO susceptibility (χ(3) = ~10−7 esu), molecular hyperpolarizability (γh = ~10−27 esu), ground state absorption cross section (σg = ~10−22 cm2) and excited state cross sections (σex= ~10−20 cm2) were determined. The chalcones also exhibited optical limiting and all optical switching behaviour for CW laser operating at 532 nm wavelengths. The electric dipole moment, polarizability, hyperpolarizabilty, HOMO-LUMO energy gap, global chemical reactivity descriptors (GCRD), molecular electrostatic potentials (MEP) and natural bond orbital (NBO) analysis were computed theoretically (DFT). The results indicate that these three chalcones with thiophene moiety are potential materials for optical device applications.

Transition metals induce control of enhanced NLO properties of functionalized organometallic complexes under laser modulations

The molecular engineering of organometallic complexes has recently attracted renewed interest on account of their potential technological applications for optoelectronics in general and optical data storage. The transition metal which induces control of enhanced nonlinear optical properties of functionalized organometallic complexes versus not only the intensity but also the polarization of the incident laser beam is original and important for all optical switching. This makes organometallic complexes valuable and suitable candidates for nonlinear optical applications. In the present work, we report the synthesis and full characterization of four organometallic complexes consisting of N, N-dibutylamine and azobenzene fragments but differ by auxiliary alkynyl ligands or metal cations. Thus, a ferrocenyl derivative 1 and three ruthenium complexes 2–4 have been prepared. The nonlinear optical properties of the four new azo-based ruthenium and iron organometallic complexes in the solid state, using polymethylmethacrylate as matrix, have been thoroughly studied. This concept is extended to computing the HOMO and LUMO energy levels of the considered complexes, dipole moment, first and second order hyperpolarizabilities using the 6–31 + G(d,p) + LANL2DZ mixed basis set. The second and third nonlinear optical properties of the resulting polymer composites were obtained by measuring SHG and THG response by means of the Maker fringe technique using a laser generating at 1,064 nm with a 30 ps pulse duration. The values of the second and third order NLO susceptibilities of the four organometallic complexes were found to be higher than the common references used. Theoretical calculation shows that the large first and second order hyperpolarizablities are caused by strong intramolecular charge transfer between the transition metal parts and the ligands though a conjugated transmitter. These results indicate that the present organometallic complexes are valuable candidates for optoelectronic and photonic applications.

Influence of bismuth nitrate doping towards the characteristics of L-Alanine nonlinear optical crystals

In the present study, an amino acid derivatives, L-alanine (LA) and Bismuth nitrate-doped L-alanine (BNLA) crystals were grown by the slow evaporation technique. The crystal structure and quality of the grown crystal were examined by single-crystal X-ray diffraction (XRD) and powder XRD. The X-ray diffraction analysis of LA and BNLA crystals confirmed the orthorhombic crystal system without any internal structural grain boundaries. The optical properties of the LA and BNLA crystals have been determined using UV-Visible spectroscopy and Photoluminescence (PL). The second harmonic generation (SHG) efficiency of the crystal was measured using Kurtz powder technique. The dielectric constant measurement was performed at room temperature for different frequencies. Photoconductivity tests show that the LA and BNLA crystals have negative photoconductivity value. On testing of the retentivity or remanent magnetization, the BNLA crystal has increased values as compared to the pure LA crystals, in addition to the observation of changes in coercivity. Further, the observation of maximum intensity peak for the BNLA crystal at 346.9 nm pointed out that the crystal has blue fluorescence emission. The third-order nonlinear optical properties of the grown crystal were studied using Z-scan technique. The enhancement in nonlinear refractive index and third-order NLO susceptibility value shows that the grown BNLA crystals may be of good quality and less in defect than that of pure LA crystals.

Investigations on structural, optical, dielectric, electronic polarizability, Z-scan and antibacterial properties of Ni/Zn/Fe2O4 nanoparticles fabricated by microwave-assisted combustion method

In this article, Ni0.5Zn0.5Fe2O4 nanoparticles (NPs) were synthesized by differing concentrations of fuel (lean, stoichiometric, and rich) via microwave-assisted combustion route. The effect of fuel content was used to explore their chemical, electrical, and nonlinear optical properties along with their antibacterial activity of the as-prepared Ni/Zn/ferrite NPs were studied. The XRD assures the cubic crystal structure of prepared NPs with no secondary phase. It is also clear that as lattice parameters increases, the mean crystallite size decreases as a change in fuel ratio. The optical energy bandgap values are estimated as 2.88, 3.28, and 3.0 eV, respectively. From the luminescence spectra, the Ni/Zn ferrite NPs exhibits strong green emission and weak violet emission color. The fuel ratio has a significant influence on the electronic polarizability properties of synthesized NPs. Closed and open aperture Z-scan technique reveals that the Ni/Zn ferrites NPs have self-defocusing nature, and reverse saturable absorption. The calculated values are NLA coefficients (10-5 cmW−1), NLR index (10−9 cm2W−1), and third-order NLO susceptibility χ(3) values of fuel lean (1.408 × 10−5esu), stoichiometric (2.75 × 10−6esu), and rich (2.634 × 10−5esu). Several identified microorganisms such as gram + Ve (S. aureus, B. cereus), and gram -Ve (P. aeruginosa, V. cholerae, and E. coli) have been tested for antibacterial activity against Ni/Zn ferrite nanoparticles. The ZOI values are 27 (lean), 24 (stoichiometric), and 25 mm (rich) which suggest great antibacterial activity against Pseudomonas aeruginosa gram-negative bacterium. However, this study shows excellent feasibility of applying prepared ferrite nanoparticles for optoelectronic devices and pharmaceutical processing applications.

Synthesis and characterization of GO doped bio-resource based composites for NLO and multifaceted applications

The objective of the present work is to synthesize three different types of cardanol based benzoxazines such as cardanol-{1,4-bis(4-aminophenoxy)ethane}benzoxazine (CBAE2Bz), cardanol-{1,4-bis(4-aminophenoxy)butane} benzoxazine (CBAE4Bz) and cardanol-{1,4-bis(4-aminophenoxy)octane}benzoxazine (CBAE8Bz) by varying aliphatic ether link chain length through solventless method. The benzoxazines obtained with varying chain length were converted in to three different types of composites using paraphenylenediamine (PPDA) functionalized gaphene oxide (f-GO) as nano-reinforcement with varying weight percentage and were characterized by different analytical techniques. The molecular structure of the monomers was confirmed from Fourier transform infrared (FTIR) spectroscopy, 1HNMR, 13C NMR and MALDI mass. Data obtained from thermal studies infer that the prepared composites possess good thermal stability and enhanced values of Tg with respect to weight percent of functionalized graphene oxide content. However, the values of thermal stability, Tg, dielectric constant and dielectric loss were marginally decreased with respect to increase in length of the spacer aliphatic chain. The SEM and TEM studies confirm the homogeneous dispersion and single layer thickness of graphene sheet, respectively. The feasibility of usage of f-GO/PCAE2Bz composite in both gram positive bacteria (Bacillus subtilis, Staphylococcus aureus) and gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli) environments were checked and the results obtained were discussed. Further, third-order NLO properties of open and closed aperture Z–scan results conclude that GO doped bio-resource based composites exhibit saturable absorption and self-defocusing type optical non-linearity. The third-order NLO susceptibility (χ3) of GO doped bio-resource based composites are increased with respect to quantity of reinforcement of GO to bio-based polymer. The maximum value of 1.03X 10−4 esu was observed and this nonlinearity is thermal in nature. Thus, the prepared composites may find wide range of applications in diverse surrounding conditions.