Hydrate Single Crystals Research Articles

One‐Step Synthesis of Melem‐Based Supramolecular Assemblies and Their Photocatalytic Properties

In this work, melem‐based supramolecular assemblies were obtained in one step by thermal treatment of melamine in an autoclave in the presence of sodium chloride. The detailed analysis showed that the obtained powder consists of two phases: poorly crystalline Na‐PHI flakes and rod‐shaped melem hydrate single crystals (several micrometers long and ~300‐500 nm wide). Melem hydrate crystals absorb light in the visible range (Eg = 2.7 eV) and demonstrate photocatalytic activity in the reaction of partial oxidation of benzyl alcohol to benzaldehyde by air under visible light with high selectivity for the target product. At 60% conversion of benzyl alcohol, the selectivity of benzaldehyde formation is above 95%.

Investigation on the growth aspects and properties of rubidium hydrogen succinate hydrate single crystal for NLO applications.

A novel semiorganic nonlinear optical single crystal of rubidium hydrogen succinate hydrate (RbHSH) was grown at room temperature using the slow evaporation solution growth technique (SEST) with water as a solvent for nonlinear optical applications. The grown crystal is a triclinic system with a centrosymmetric space group of P1̄ and the compound is stabilized by intramolecular O-H-O and C-H-O bonding. FTIR spectral studies were used to determine the various functional groups present in the material. The optical transmission spectra of the grown crystal demonstrated that a transparency of 89%, with a low cut off wavelength of 240 nm and an energy band gap of 5.21 eV, which is beneficial to developing advanced photonic and optoelectronic devices in the solar blind UV area. The grown crystal is thermally stable upto 174 °C. The electrical properties of RbHSH crystal exhibit low dielectric loss and a low dielectric constant at high frequencies tends to have good optical characteristics. Mechanical analysis demonstrated that the grown crystal shows the normal indentation size effect (ISE) and falls into the hard material category with n = 1.4. Photoconductivity measurements revealed negative photoconductivity. Photoluminescence studies showed that RbHSH emits blue light with a wavelength of 484 nm. Hirshfeld surface analysis was used to analyze intermolecular interactions in the RbHSH crystal. The grown RbHSH crystal piezoelectric charge coefficient have been calculated (d33 = 13 pC N-1) and it is suitable for piezoelectric device applications. Under continuous-wave laser excitation, the third order nonlinear refractive index (n2), absorption coefficient (β), and susceptibility (χ(3)) of the RbHSH crystal were found to be 1.6639 × 10-12 (cm2 W-1), 1.1739 × 10-5 (cm W-1) and 4.86331 × 10-9 esu, respectively.

Investigation on the growth, structure and physical properties of pyridin-1-ium-2-carboxylate benzimidazole (1:1) hydrate single crystal

Investigation on the growth, structure and physical properties of pyridin-1-ium-2-carboxylate benzimidazole (1:1) hydrate single crystal

In Situ Investigation on the Morphology and Formation Kinetics of a CO2/N2 Mixed Hydrate Film

The influence of N2 molecules on the morphology and growth kinetics of CO2 hydrate films under different gas compositions and subcooling degrees (ΔT) was studied using a gas bubble suspended in water and in situ Raman spectroscopy, and some perspectives about the CO2/N2-CH4 replacement were put forth in this work. The evolution morphologies and formation of hydrate films were studied via optical microscopy and in situ Raman spectroscopy, respectively. The results demonstrated that the size of the hydrate single crystal on the hydrate film was related to the N2 concentration and ΔT; the roughness of the hydrate film was inversely proportional to the N2 content and ΔT; and the hydrate formation rate was highest in the 80% CO2 + 20% N2 gas system, in which the function of N2 on the hydrate formation may primarily be to improve the hydrate film’s roughness and enlarge the gas pore size on the film, which makes molecular mass transfer easier to carry out, and to stabilize the CO2 hydrate structure. Raman results showed that the amount of CO2 stored in the hydrate phase was still greater than that of N2 molecules due to CO2 molecules being more stable in the hydrate phase, despite the fact that N2 molecules were more competitive for mass transfer during the evolution of hydrate films because of their smaller size. With an increase in N2 concentration and ΔT, the amount of CO2 molecules trapped in the hydrate phase decreased, which is partly due to the low concentration of CO2 in the gas mixture as well as the fact that the hydrate film was much dense and impeded mass transfer of CO2 molecules. The experimental results implied that the morphology of the hydrate film and the composition of the CO2/N2 mixed gas are important to achieve better replacement efficiency during the exploitation of natural gas hydrates via the CO2/N2-CH4 replacement method.

Releasable Water Charge-Trapping and Water-Resistant Photodetection using 1D Perovskitoid Hydrate Single Crystal.

Hydrates of hybrid organic-inorganic perovskites have been discovered with MAPbI3 and are proved to be unstable in atmosphere. However, the influence of water molecules on the performance of optoelectronic devices is still not fully understood. Here, using a dication, 2-(dimethylamino) ethylamine (DMEN2+ ), a stable quasi-1Dperovskitoid hydrate single crystal is designed and successfully synthesized, which is formulated as DMENPb2 I6 ·H2 O. In this design, both corner-sharing and edge-sharing connectivity are adopted, and water molecules are connected with the crystal through hydrogen bonding. It is discovered that such water sites distributed along the inorganic chains function both as charge traps and as releasable charge stocks. Optical excitation that overcomes the potential wells formed on these water sites may release these stocked charges and facilitate enhanced transportable charge density. Meanwhile, exciton diffusion and charge transport are strongly confined in the 1D transport channels. Above mechanisms are verified both by the transient absorption spectroscopy and by the photodetection performance. This introduces a new design strategy with a trapping-stock-releasing-transport roadmap for perovskitoid materials. Excellent water resistance endows this material with more advantages in the development of a new generation of optoelectronic devices.

Investigations on nucleation kinetics and dielectric behavior of potassium DL-malato borate hydrate (C8H10BKO11) single crystal

A single transparent crystal of potassium DL-malato borate was grown with the help of solvent evaporation technique. The lattice parameters, a = 11.3571 Å, b = 5.3225 Å, c = 21.2348 Å and α = β = γ = 90° with space group Pna21 of the grown crystal was confirmed by using the single crystal XRD analysis. The solubility of the compound was measured with the help of gravimetric analysis. The polythermal method was adopted for the determination of the metastable zone width. The solubility curve indicates that the material exhibited a positive temperature gradient of solubility. The induction period of the grown material was measured with the help of the isothermal method. It was found to decrease with increasing the supersaturation ratio and temperature. Various nucleation parameters were calculated with the help of the classical theory of nucleation, which was required for optimizing the growth condition for the growth of the good quality crystal. The low value of the dielectric loss and constant value for high applied frequency ensure the application of this material in device fabrication. The third-order nonlinear properties of the grown crystal were studied with the aid of the Z-scan technique.

Growth rate and morphology study of tetrahydrofuran hydrate single crystals and the effect of salt

Single crystals of sII THF hydrate grown using a seed/template method demonstrated an increase in growth rates. With 3.5 wt% NaCl, the growth rates are lower, resulting in a morphology of parallel intergrowths of octahedral crystals.

Investigation on third-order nonlinear parameters, mechanical and dielectric behavior of alkali metal-organic C2HLiO4 H2O single crystal

A metal-organic lithium hydrogen oxalate hydrate single crystal was developed using the solution growth method. The single-crystal XRD analysis confirmed the triclinic structure and space group P1 along with the lattice parameters a = 3.439 Å, b = 5.097 Å, c = 6.141 Å, α = 78.50°, β = 84.89°, and γ = 81.41° of the grown crystal. The average crystallite size and strain within the material were calculated and compared using Debye Scherrer and Williamson-Hall method. The existence of diverse functional groups in the LHOH crystal was verified with the help of the FTIR analysis. The Z-scan method was carried out to acquire information about the developed material's third-order nonlinear characteristics that showed the material's self-focusing effect. The dielectric behavior of the compound was studied for various temperatures and frequencies. The Vicker’s microhardness analysis was carried out to collect information about the hardness number, yield strength, elastic stiffness, brittle index and fracture toughness of the grown crystal. The hardness number decreased when the applied load was increased, which indicated the normal indentation effect of the material.

Enhanced third-order nonlinear optical properties of methyl orange dye-doped potassium penta borate octa hydrate (MOPPB) single crystals using CW diode laser for optical limiting applications

We report pure potassium penta borate octa hydrate (PPB) and methyl orange dye-doped potassium penta borate octa hydrate (MOPPB) for optical limiting applications. The crystals were grown by slow evaporation solution growth technique at ambient conditions. The single crystal X-ray diffraction (SXRD) evinces the orthorhombic class of the pristine and MOPPB crystals. Formation of PPB and incorporation of MO dye in PPB was confirmed through Fourier transform infrared (FTIR) study. Calculated hardness number and stiffness constant with Vicker’s Micro hardness study portrays the soft nature of the title crystals. The decrease in bandgap of MOPPB is due to the additional energy levels introduced between the valence band and conduction band which in turn increases the net polarizability of the crystal. Relative second harmonic generation (SHG) efficiency of pure PPB and MOPPB is 0.45 times and 0.40 times that of SHG output of KDP. Z-scan studies shows that both crystals show reverse saturable absorption (RSA) ascribed due to two-photon absorption (TPA) process. MOPPB [β = 1.68 × 10–5 m/W, n2 = 10.2 × 10–12 m2/W, χ(3) = 3.5 × 10–9 m2/V2] possess higher NLO coefficients than pure PPB [β = 0.98 × 10–5 m/W, n2 = 4.62 × 10–12 m2/W, χ(3) = 6.1 × 10–9 m2/V2] which assured the superiority of azo dye incorporation in PPB crystals. Pristine and MOPPB crystals depict the optical limiting (OL) behavior under continuous wave (CW) diode laser irradiation at 785 nm. Thus, the linear and nonlinear properties bestow the MOPPB single crystal as a versed material for OL devices used for the safeguard of optical components from laser damage.

Comments on the paper “Synthesis and characterization of inorganic nonlinear optical material: Potassium sodium hydroxide borate hydrate (KSB) single crystal”

The authors of the title paper (Mater. Lett. 188 (2017) 156–158) claimed to have grown potassium sodium hydroxide borate hydrate (KSB) single crystal and reported its mechanical properties in a subsequent paper (Mater. Lett. 215 (2018) 165–168). In this letter, many points of criticism concerning the crystal growth, structure characterization and interpretation of the spectral and thermal data of the so-called KSB crystal are described to prove that it is a dubious material.

Structural, linear and non linear optical, electrical, piezoelectric and thermal investigation on new semi-organic single crystal for microelectronics and high power laser applications: A brucinium di-hydrogen borate hydrate

Abstract The fine quality of brucinium di-hydrogen borate hydrate (BDHBH) single crystal was harvested from the saturation solution by slow evaporation technique. Crystal structure was solved by SHELEX program and which confirms that the title crystal belongs to monoclinic crystal system with non-centro symmetric space group P21. Linear optical parameters such as transparency range, cut-off wavelength, optical band gap, electro-negativity and refractive index of the title crystal were computed by UV–Visible study. The high surface laser threshold damage (SLDT) value shows its suitability in laser application coupled with high power output. Second order non-linear behavior was confirmed by Kurtz-Perry powder technique. The lesser value of FWHM shows the better quality of the grown crystal. Title compound is a utensil candidate for blue emission applications in field of optical device fabrications which is demonstrated by fluorescence optical study. The grown crystal exhibits RISE which is analyzed by Viker's micro hardness measurements. Dielectric study shows, the dielectric constant decreases exponentially by increasing frequency which confirms the normal dielectric performance and low dielectric loss indicates that, the lower concentration of defects in the title compound. Piezoelectric charge coefficient and piezo-voltage of BDHBH crystal were found to be 2 p C/N and 0.0175 p V m N−1 respectively. The multiple decomposition stages of the title compound were discussed in detail by various thermal analyses such as TGA, DTA and DSC.

Novel report on structural, optical and electrical investigation into brucinium 4-methyl-3-nitrobenzoate 0.5 hydrate single crystal: a promising material for high-power laser, ultrahigh cooling, sensor and detector applications

A new brucinium 4-methyl-3-nitrobenzoate 0.5 hydrate (B4M3NB0.5H) NLO single crystal was harvested from saturated solution by solvent evaporation method. Crystal system and symmetric type of B4M3NB0.5H compound were analyzed by structure analysis. Linear optical parameters of title compound were discussed in detail by UV–visible analysis. Lifetime values of the molecule were quantified by fluorescence study, and it confirms the good crystalline perfection of the grown crystal. The SHG efficiency is 5.11 times superior to the KDP material. By utilizing Nd:YAG laser as an input, SLDT measurement of the crystal was done. The grown crystal has good crystalline nature which is analyzed by HRXRD study. Dielectric behavior of B4M3NB0.5H crystal was discussed in detail. With the help of theoretical approach, few of the solid-state parameters were calculated and listed. Piezoelectric charge coefficient and piezovoltage were calculated to be 4.5 p C/N and 0.0417 p V m/N, respectively. The TGA and DTA spectrum confirms that the title compound is thermally stable up to 101 °C.

Growth and Characterization Studies of L-Arginine Doped Zinc Sulphate Mono Hydrate Single Crystals

Single crystals of L arginine doped zinc sulphate mono hydrate were grown by adopting slow evaporation method. Crystalline nature of the material was verified with powder X ray diffraction analysis. The presence of zinc, sulphur and L arginine was confirmed through EDAX and FTIR analyses. Optical studies established the transparent nature of the grown crystal. Vickers micro hardness study proved the soft nature of the crystal. Thermo gravimetric analysis established the melting point of the grown crystal.

Structural, optical and piezoelectric investigation on brucinium bromide hydrate non linear optical single crystal for optical parametric oscillators, high-power laser, piezo-sensors and transducers applications

In the present work, a good transparent semi-organic brucinium bromide hydrate (BBH) single crystal was grown from the saturated solution by slow evaporation method. The single crystal XRD study reveals that, BBH crystallize in Triclinic crystal system with non-centrosymmetric space group P1. Presences of chemical elements such as Carbon, Hydrogen and Nitrogen are C = 38.79%, H = 44.10% and N = 3.48% respectively. The morphological study concludes that, the growth rate along ‘c’ direction is more expeditious than that of a & b. The UV–Visible spectrum confirms the good transparency of the crystal and diverse optical parameters such as cut-off wavelength, band gap, UV-resonance energy and refractive index values were calculated and relation between the different optical parameters were also discussed in detail. Chemical bonding nature of BBH crystal was identified with the aid of optical electro-negativity value. The Urbach energy value was found to be 0.1238 eV. LDT value of BBH crystal was found to be 6.43 GW/cm2 and it is compared with other standard materials such as KTP, KDP and Urea. To find the suitability of crystal in the field of nonlinear optical application, the second harmonic generation value was determined using Kurtz-Perry powder technique. The spectroscopic investigations were done by vibrational analysis in order to identify the different functional groups in BBH compound. The value of piezo-electric charge co-efficient (d33) was quantified by PM-300 piezometer. Fluorescence spectral study provides the knowledge about electron excitation and also life time of the molecules. Title crystal does not contain any internal structural grain boundaries which are confirmed by HRXRD analysis.

Investigation on organic-inorganic hybrid NLO crystal L-Valine Potassium Penta Borate octa hydrate (LVPPB) for NLO applications

An organic-inorganic non linear optical (NLO) crystal L-Valine Potassium Penta Borate octa hydrate (LVPPB) single crystals were synthesized and grown by slow evaporation technique at ambient temperature. The single crystal X-Ray diffraction (XRD) analysis portrayed the monoclinic nature of the synthesized crystal. The UV–vis cut off wavelength was observed as 225 nm. The various functional groups CH3, CH, NH3 COO_, BO3, BO4 and KO in LVPPB were identified using the Fourier transform infrared (FTIR) technique. The thermogravimetric and differential thermal analysis (TG-DTA) thermogram was utilized to determine the thermal stability of the grown crystal. The work hardening co-efficient was calculated as 2, using microhardness study. The second harmonic generation (SHG) efficiency of the LVPPB was found to be 0.9 times that of KDP.

Enhanced physical properties of potassium zinc sulphate hydrate single crystal following iodide doping

The crystal grown from mixing potassium iodide and zinc sulphate in an aqueous solution was found to be a single crystal potassium zinc sulphate hydrate. The iodide ions enter the crystal matrix as a dopant with small ratio. The evaluation of the crystal structure was achieved by single crystal diffraction and the resolved structure was monoclinic with space group P21/c. The effect of iodide doping is observed in the crystal morphology and the x-ray powder diffraction pattern. The iodide ions were detected in the grown crystal using x-ray fluorescence and energy dispersive x-ray which spotted a very small fraction of iodide in the raw materials of the crystal. The iodide doping also affected the thermal stability of the original crystal and introduced different thermal behavior. The optical properties are also affected and a noticeable band in the transmittance is observed. The iodide effect on the structure of optical energy gap is analyzed using photoluminescence spectra. Second harmonic generation test shows an unexpected behavior based on the structure of the grown crystal.

Novel report on SHG efficiency, Z-scan, laser damage threshold, photoluminescence, dielectric and surface microscopic studies of hybrid inorganic ammonium zinc sulphate hydrate single crystal

Hybrid inorganic nonlinear optical crystals find huge applications in laser assisted photonic devices therefore present communication firstly aims to investigate the dielectric, microscopic and linear-nonlinear optical properties of ammonium zinc sulphate hydrate (AZSH) crystal. The inorganic AZSH complex has been synthesized and 15 × 10 × 09 mm3 single crystal was grown by slow solvent evaporation method. The powder and single crystal X-ray diffraction technique has been employed to evaluate the crystalline phase and determine the structural parameters of AZSH crystal. The optical transparency of AZSH crystal has been examined within the wavelength rage of 200–1100 nm. The enhanced second harmonic generation efficiency of AZSH crystal is 2.53 times higher than standard KDP crystal. The laser damage threshold of AZSH crystal has been determined using the Nd:YAG laser operating at 1064 nm. The close and open aperture Z-scan studies have been performed to ascertain the nature of third order nonlinear optical (TONLO) refraction and absorption of AZSH crystal. The order of TONLO parameters n2, β and χ3 is found to be 10−9 cm2/W, 10−4 cm/W, 10−4 esu respectively. The AZSH crystal is found to have violet colored luminescence emission centered at 370 nm. The dielectric constant and dielectric loss of AZSH crystal has been evaluated within 30 Hz to 1 MHz. The chemical etching technique has been imposed to examine the growth habitat and determine the etch pit density of AZSH crystal.

Investigation of inorganic nonlinear optical potassium penta borate tetra hydrate (PPBTH) single crystals grown by slow evaporation method

Borates family crystals were plays vital role in the field of non linear optics (NLO) due to needs of wide range of applications. In this report, NLO crystals (potassium penta borate tetra hydrate (KB5H8O12) are grown by slow evaporation method at room temperature (28° C) and studied their physical properties. The harvested single crystals are transparent with the dimension of 12 × 10 × 6 mm3 and colourless. X-ray diffraction of single crystals reveals that the grown crystal belongs to orthorhombic system with non-centrosymmetric space group Pba2. All the absorbed functional groups are present in the order of inorganic compounds expect 1688 cm−1 because of water (OH O blending) molecule present in the pristine. Crystals show transparent in the entire visible region with 5.9 eV optical band gap and also it shows excellence in both second and third order nonlinear optical properties. Crystals can withstand upto 154 °C without any phase changes which is observed using thermal (TGA/DTA) analysis.

Study on the mechanical properties of potassium sodium hydroxide borate hydrate (KSB) single crystals by using Vickers microhardness tester

The mechanical properties of solution grown potassium sodium hydroxide borate hydrate single crystal (KSB) have been obtained by using Vickers microhardness studies in the load range from 10 to 70 g. The variation of microhardness with load represents the load independent value of hardness (Indentation size effect). The meyer’s index number ‘n’ is calculated as 1.81 and it belongs to soft material category. Various mechanical parameters such as yield strength, elastic stiffness constant, fracture toughness, brittleness index, hardness contour and crack propagation of KSB single crystal are discussed in detail.

Investigation about nonlinear optics and antibacterial activity of pyrrolidine-2-carboxylic acid cadmium chloride hydrate single crystal

This work intends to investigate the superior properties of Pyrrolidine-2-carboxylic acid Cadmium Chloride Hydrate (PCCH) that was grown by the slow evaporation technique at room temperature. The crystalline nature of PCCH was found by powder X-ray diffraction analysis. The optical behaviour of the grown crystal was unveiled by using UV-vis-NIR. The refractive index of the crystal was measured experimentally using Metricon prism coupler for the first time. The z-scan measurement was taken to explore the third harmonic generation efficiency of the grown crystal for the first time. The structural imperfections were analyzed by performing the etching studies on the grown crystal. The first attempt of antibacterial activity of this crystal was carried at different concentrations (25, 50, 75 and 100μg/mL) in-vitro against Staphylococcus epidermis (G+Ve); Escherichia coli, Vibrio cholera (G–Ve) bacteria. These studies established that PCCH crystals might find useful applications in the field of biomedical and nonlinear optics.