A noncentrosymmetric chalcone derivative (E)-1-(thiophen-2-yl)-3-(3, 4, 5-trimethoxyphenyl) prop-2-en-1-one (TTMP) was synthesized using Claisen Schmidt condensation approach and single crystals were ...grown using slow evaporation method. The grown TTMP crystals crystallizes in orthorhombic structure with Pna21 space group. The intermolecular interactions of the TTMP crystals were envisioned by Hirshfeld surface analysis (HSA). Further, the structural conformations of the crystal were carried out by using 1H NMR, FTIR, and FT-Raman spectral analysis. The UV–Vis–NIR spectrum of the sample clearly shows the prime transparency in the entire visible and near infrared region. Thermal studies (TG/DTA/DSC) of the TTMP sample shows excellent thermal stability and phase transition and also noticed that crystal was most stable up to 152.65 °C. The second harmonic generation efficiency was obtained for the crystals using Nd:YAG laser and is to be 1.93 times that of urea. The third order nonlinear absorption coefficient (β), nonlinear refractive index (n2), third-order nonlinear susceptibilities (χ (3)), second order hyper polarizability (γh) and optical limiting thresholds were determined by Z-scan technique using the Diode-Pumped Solid State (DPSS) Continuous Wave (CW) laser. The results suggest that the TTMP molecules are promising materials for optoelectronic device applications.
•2-acetyl thiophene and 3,4,5 trimethoxy benzaldehyde were used for synthesis.•Thermal properties were studied using DSC/ TG/DTA Analysis.•Nonlinear absorption (NLA) coefficients (β ~ 10-6 cmW-1).•Nonlinear refractive index (NRI) (n2 ~10-10cm2W-1).•Third-order NLO susceptibilities (χ(3) ~10-7 esu) were determined.
A novel optically high-transparent chalcone derivative (E)-3-(3-nitrophenyl)-1-(thiophene-2-yl)prop-2-en-1-one (2AT3N) has been synthesized and crystallized using slow evaporation solution method. ...The grown single crystals were characterized by FT-IR and FT-RAMAN vibrational technique. The spectroscopic investigations confirmed the presence of various functional groups in the grown single crystals. The single crystal X-ray diffraction analysis revealed that the harvested single crystals possess triclinic crystal structure under centrosymmetric space group P-1. In addition, the intermolecular interactions in the molecule were figured out by Hirshfeld surface analysis. The 2AT3N crystal possesses high optical transmittance beyond cutoff wavelength (358 nm) in the entire visible region. The thermal stability of the crystals has been examined by TG/DTA/DSC measurements. The 2AT3N crystals are thermally stable up to 148.3 °C. The third-order nonlinear optical properties have been studied using Z-scan experiment (532 nm and 200 mW). The Z-scan Experimental results reveal that the 2AT3N single crystals show high-order nonlinear absorption coefficient (
β
~ 10
−5
cm W
−1
) and nonlinear refractive index (
n
2
~ 10
−9
cm
2
W
−1
). The optical limiting study on 2AT3N was carried out using open aperture Z-scan data. The grown single crystals possess reverse saturation absorption (RSA) due to excited state absorption. The structural and nonlinear optical property relationship of the molecule along with the role of nitro group substitution in the enhancement of nonlinear optical property has been discussed in detail. Nonlinear optical studies show that, the synthesized novel chalcone derivative is an advisable material for nonlinear optical applications such as optical limiter and optical switches.
The influence of optimal ultraviolet irradiation of Nafion membranes in enhancing proton conductivity and performance of passive micro-direct methanol fuel cells with silicon micro-flow channels is ...investigated for the first time. Initially, Nafion membranes are irradiated with different doses of ultraviolet radiation ranging within 0–400 mJ cm−2 and their water uptake, swelling-ratios, porosity, and proton conductivities are measured using standard procedure. Results show that there is an enhancement in proton conductivity with an optimal dose of 198 mJ cm−2 ultraviolet radiation. This enhancement is due to optimum photo-crosslinking of –SO3H species resulting in maximum pore-size which facilitates enhanced proton-hopping from one –SO3H site to another in the hydrophilic channel. Nafion membranes with three different thicknesses (50 μm, 90 μm and 183 μm) are irradiated with ultraviolet radiation with 198 mJ cm−2 dose and passive micro-direct methanol fuel cells are assembled with irradiated Nafion proton exchange membranes. The polarization plots are obtained for the assembled devices. Results show an enhancement of power density of devices nearly by a factor of 1.2–1.5 with optimally irradiated membranes indicating that optimum dose of ultraviolet irradiation of Nafion membranes is an effective technique for power enhancement of proton exchange membrane fuel cells which use fuels like methanol, ethanol and hydrogen.
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•Pore size tuning of Nafion membranes is achieved by irradiation with UV rays.•Optimum dose of UV rays on Nafion results in enhancement of proton conductivity.•Microelectromechanical systems technology is used to define flow channels in silicon.•UV exposed Nafion is tested in passive direct methanol fuel cells as a platform.•Durability test of direct methanol fuel cells with UV exposed Nafion is carried out.
A thiophene based bromo substituted novel chalcone derivative (E) -3-(4-bromophenyl)-1-(thiophen -2yl) prop-2-en-1-one (2AT4B) is synthesized and crystals are grown using solution slow evaporation ...method at ambient temperature. The single crystal XRD analysis is accomplished to confirm the three dimensional structure of the grown crystals and 2AT4B crystallizes with orthorhombic crystal system under centrosymmetric space group Pbca with the lattice parameters a = 6.0073(6) Å, b = 13.9765(14) Å, c = 28.1(3) Å, α=β=γ=900 and V = 2359.3(4) Å3. The functional groups and material purity is confirmed by FT-IR, proton NMR, and carbon NMR techniques. The crystal is subjected to mechanical and thermal analysis using vicker's microhardness test, differential scanning calorimetric, and thermogravimetric measurements and is thermally stable up to 134.04 °C. The synthesized molecule was characterized by UV–Vis–NIR spectrometer. The photoluminescence spectrum reveals violet light emission property 2AT4B crystal. In the visible region, 2AT4B crystal processes extensive optical transmission. In a continuous wave mode, the third-order NLO parameters are measured with Z-Scan technique. The open aperture data was used to study the optical limiting behaviour of chalcone crystal. Nonlinear optical studies show that the 2AT4B crystal is a promising source for applications in photonic and optical power limiting devices.
•The single crystal XRD analysis: Orthorhombic crystal system under centrosymmetric space group Pbca.•Thermal stability upto 134.04 °C, Microhardness better than standard crystal urea Hv = 16 kg/mm2.•Nonlinear absorption coefficients and Nonlinear refractive index: (β ~ 10−5 cmW−1) and (n2 ~10−9 cm2W−1).•Photoluminescence: Violet light emission property.•Optical limiting threshold: 3.01 kJ/cm2.
The work presented here reported the thickness dependent structural, linear and nonlinear optical properties of nanostructured Cd
1−
x
Zn
x
O thin films. Thin films were prepared with two different ...thickness (≈ 0.5 µm and 1 µm) by employing a spray pyrolysis (SP) technique for different Zn-doping levels (Cd
1−
x
Zn
x
O with the
x
value of 0.00, 0.01, 0.05 and 0.1). X-ray diffraction studies confirm the polycrystalline nature having a cubic crystal structure. In terms of an aspect ratio of the columnar structure and dispersion in hexagonal (1 1 1) basal plane orientation, a thickness dependency of structural evolution was discussed. The Scherrer rule was employed to determine the crystallite size and found to be decreased. FESEM images indicate grains which are uniform and grain size slightly increased with an increase in dopant concentration, annealing and thickness of the films, respectively. The optical energy band gap (
E
g
) of the prepared films was found to be increased from 2.50 to 2.67 eV. The NLO parameters of the samples were measured from the Z-scan data under DPSS continuous wave laser excitation at 532 nm and the results reveal that reverse saturable absorption (RSA) and self-defocusing natures are the attributed and observed nonlinearity of the nanostructures. The third-order NLO components such as
β
,
n
2
and
χ
(3)
are found to be enhanced with one order of magnitude higher with the influence of thickness from 1.25 × 10
–4
to 2.47 × 10
–3
(cm W
−1
), 7.08 × 10
–9
to 3.35 × 10
–8
(cm
2
W
−1
) and 4.06 × 10
–7
to 1.96 × 10
–6
(esu) respectively. The inspiring results of NLO parameters are also due to the increasing localized defect states on grain boundaries as the film thickness increases, suggesting the prepared films are a promising material for nonlinear photonic device applications.
•The single crystal XRD: Polymorphic nature under centrosymmetric space group P 21/c.•Thermal stability up to 131.02 °C and Microhardness Hv =21 kg/mm2.•Wide optical transparency in the visible ...region and Blue light emission property.•Third order nonlinear optical susceptibility χ(3): 1.66 × 10−7(esu).•Optical limiting threshold: 2.674 kJ/cm2.
The polymorphic molecule of (E)-1-(thiophen-2-yl)-3-(4-chlorophenyl) prop-2-en-1-one (2AT4C) was synthesized and grown its single crystals using slow evaporation solution growth technique. The molecular geometry and its structural deviations are studied using single crystal x-ray diffraction method. Further, for the 2AT4C molecule, the intermolecular interactions and the percentage of interactions using 2D fingerprint plots were analyzed by Hirshfeld surface analysis. The FT-IR and FT-Raman spectroscopic techniques confirm the presence of bonding, stability of coordination compounds, and material validation. The physical properties of 2AT4C crystal have been discussed using simultaneous TG/DTA/DSC thermal analysis and the vicker's microhardness test. Their physical stability in terms of melting point and vicker's hardness number was found to be 131.02 °C and Hv=21kg/mm2 respectively. PL studies project the blue light emission (378 nm) property of the grown crystal and UV-visible spectroscopic study reveals the wide optical transparency in the entire visible region with an optical band gap 3.47 eV. The third order nonlinear optical parameters such as nonlinear absorption coefficient, nonlinear refractive index, optical susceptibility, and optical limiting threshold were measured using z-scan technique under CW regime. The outstanding results of the various measures are confirms the potentiality of 2AT4C crystal for nonlinear and optoelectronic device applications.
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A new organic nonlinear optical material 3-(4-chlorophenyl)-1-(pyridin-3-yl) prop-2-en-1-one (CPP) having high second harmonic generation efficiency has been synthesized by a Claisen–Schmidt ...condensation reaction method. Single crystals of CPP were grown by a slow evaporation solution growth technique. The details about the various functional groups present are obtained by FTIR, FT-Raman and 1H NMR spectroscopic studies. The single-crystal X-ray diffraction (XRD) shows that CPP crystallizes in a monoclinic crystal system with noncentrosymmetric space group P21 and the cell parameters are a=5.9339(2)Å, b=4.8881(2)Å, c=19.7804(8)Å and V=568.21(4)Å3. The second harmonic generation (SHG) efficiency of the crystal is 3.67 times that of Urea. The molecular dipoles aligned in zig-zag head to tail fashion along the crystallographic b-axis result in a net polarization and hence large SHG conversion efficiency. From UV–visible study it is found that the crystal is transparent in the entire visible region. The energy band gap of the material is found using Tauc׳s plot and by a direct method. The molecular origin of SHG efficiency is discussed in detail based on the experimental results. The position of nitrogen atom in the pyridine ring has considerable effect on the NLO response of the chalcone derivatives. The crystal is thermally stable up to 133°C and can be used for NLO device applications.
•New highly efficient NLO single crystals are grown by a slow evaporation technique.•The pyridine ring plays a significant role on the NLO property of chalcones.•The molecular dipoles aligned in zigzag head to tail fashion result in large SHG efficiency.•The single electron donor substituted at the para position of the phenylene moiety increases the SHG efficiency.
The work presented here reports the influence of Aluminium (Al) doping on CdS thin films for the structural, morphological, optical and third-order nonlinear optical (NLO) properties. Thin films of ...Pure CdS and Al-doped CdS (Cd1-xAlxS) with x = 0, 0.01, 0.05 and 0.1 are prepared on the glass substrate at 350 °C using the spray pyrolysis technique. The observed X-Ray Diffraction (XRD) patterns of CdS films are found to a polycrystalline hexagonal structure and are not much affected by Al doping. Also the films have been examined by Field Emission Scanning Electron Microscopy (FESEM) images. The transmittance of the CdS films is observed to be 50–60% in the visible region and that decreased at higher doping concentrations and with higher Al doping the direct optical band gap is decreased from 2.52 to 2.38 eV. To understand the defect states characteristics, the corresponding room-temperature photoluminescence (RTPL) spectra have also been taken and found the nonlinear behavior in a band to band-edge emission in the prepared samples upon Al incorporation. The sign and the magnitude of the third-order NLO properties were determined using the Z-scan technique with a continuous wave laser as the excitation source. It is observed that the material exhibit strong two-photon absorption (2PA) with the nonlinear absorption (NLA) coefficient (β) in the range of 10−4 cmW−1 and nonlinear refractive index (NRI) n2 ∼10−9 cm2W−1. The third-order NLO susceptibility has found to be enhanced from 3.12 × 10−5 esu to 6.36 × 10−5 esu upon Al incorporation. Optical limiting characteristics of the prepared films are studied at the experimental wavelength. The results suggest that the Cd1-xAlxS is a promising material for nonlinear optical devices at 532 nm and optical power limiting applications.
•Pure CdS and Al doped CdS (Cd1-xAlxS) thin films with x = 0, 0.01, 0.05 and 0.1 were deposited on glass substrate at 350 °C using spray pyrolysis technique.•Optical study reveals that Al doping decreases the optical energy band gap. The fabricated films possess moderate optical transparency and high absorbance.•The corresponding room temperature photoluminescence spectra provided the understanding of optical properties and defect states characteristics.•The material exhibit strong two-photon absorption (2PA) and the third-order nonlinear optical (NLO) susceptibilities.•The encouraging results of NLO studies suggest that the Cd1-xAlxS thin films are promising materials for photonic devices and optical power limiting (OPL) applications.
