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We report the synthesis and characterization of multifunctional polysilane copolymers containing chiral and azobenzene chromophore as a pendant group. Multifunctional polymers of poly(methylphenylsilane) (PMPS) with (R)-N-(1-phenylethyl)methacrylamide (R-NPEMAM) and disperse red 1 methacrylate (DR1MA) were synthesized in a quartz tube using UV-technique. The molecular weights of such synthesized copolymers were found to be in the order of 103. The appearance of two glass transition temperatures in DSC indicated that the synthesized copolymers are block copolymers. The electronic absorbance of synthesized polymers was observed at 272 nm (π-π* transition of aromatic ring), 330 nm (σ-σ* transition of Si-Si chain of PMPS) and 475 nm (n-π* with π-π* transition due to azobenzene chromophore of DR1MA unit). The chirality of the synthesized polymer was confirmed through circular dichroism observed at 261 nm. Induced chirality appeared at 330 nm and 470 nm due to the association of the Si-Si chain of PMPS and the presence of azobenzene chromophore of the DR1MA unit respectively. The photoluminescence (PL) properties of the synthesized copolymers (SCDRDM-1B, SCDRDM-2B, and SCDRDM-3B) were observed at 307 nm and 415 nm when excited at 275 nm. The λem was also observed at 415 nm when excited by 325 nm. The multi-emission spectra appeared at 500 nm, 550 and 590 nm are presumed to be due to exciton coupling between azobenzene chromophore of DR1MA, and Si-Si σ-conjugation in association with the aromatic ring of PMPS and chiral unit R-NPEMAM block. [ABSTRACT FROM AUTHOR]

AbstractChemical warfare agents (CWAs) are the most feared toxic chemicals intended to debilitate the general human population and regional civilians. Therefore, prompt and urgent decontamination is needed to protect millions of lives and the associated hazardous implications. In this present study, our main goal is to evaluate the performance of Zeolite-Alpha and its various metal oxide composites as novel adsorbents for the decontamination of CWA simulants, 2-chloroethyl ethyl sulfide (CEES), and dimethyl methyl phosphonate (DMMP). Synthesized Zeolite-Alpha and their composites were characterized by XRD, FTIR, SEM-EDS, and BET analysis techniques. The CWA simulants’ decontamination (adsorption and desorption) was monitored using GC-FID and GC-MS analysis techniques. A possible reaction mechanism toward the adsorption and destruction of CWA simulants, CEES, and DMMP was also proposed. Nanocrystalline Zeolite-Alpha and its metal oxide composites are powerful adsorbents, and they showed more significant decontamination potential toward the above CWA simulants. The Cr-O-Alpha and Ag-O-Alpha showed promising results (93–98% decontamination) among all other synthesized metal oxide composites. [ABSTRACT FROM AUTHOR]

A simple and versatile method for the synthesis of 1,5-benzodiazepines is via condensation of o-phenylenediamines (OPDA) and ketones in the presence of catalytic amount of H-MCM-22 using acetonitrile as solvent at room temperature. In all the cases, the reactions are highly selective and are completed within 1-3 h. The method is applicable to both cyclic and acyclic ketones without significant differences. The reaction proceeds efficiently under ambient conditions with good-to-excellent yields. [ABSTRACT FROM AUTHOR]

Sorption and desorption of UO2 2+, Th4+ and Ru3+ on the synthetic analogue of the mica mineral muscovite has been studied by a batch technique. The synthesized gel was characterized by XRD, EDXRFS, FTIR, TGA and SEM and was found to have a composition K1.4Al4.2(Si6Al2O20)(OH)4 . 2H2O. Different parameters like acid concentration, contact time, amount of gel, composition of gel: OPC admixture, effect of temperature, desorption of metal ions from loaded muscovite and effect on crystal morphology due to loading of metal ions were studied. The results has been expressed in terms of distribution coefficient ( K d). [ABSTRACT FROM AUTHOR]

Zeolite nanoparticles are synthesized by hydrothermal method, and zeolite polypyrrole polymer nanocomposite is chemically polymerized. The polymer nanocomposite of zeolite polypyrrole is used as the gas sensing material. The sensor can detect the ammonia of the lowest concentration of 1 ppm with a response and recovery time of less than a minute. The sensor has a sensitivity of 12.34 ppm−1. The polymer composite can also degrade the methylene blue dye in the presence of UV light up to 79.4%. The powder X-ray diffraction of the materials shows the crystalline nature. The scanning electron microscope micrograph of the zeolite shows the regular hexagonal rod structure having an average length of 77.64 nm and diameter of 23.52 nm. In the case of the zeolite polypyrrole SEM micrograph, polypyrrole is encapsulating the zeolite, and also shows the polypyrrole spherical balls. [ABSTRACT FROM AUTHOR]

Present manuscript reports the hydrothermal synthesis of pristine (Zn 2 SnO 4) and copper doped Zn 2 SnO 4 spinals under subcritical conditions. XRD pattern identifies the cubic phase of pristine and its doped nanostructures. Tauc plot and density functional theory (DFT) studies claim the lowering of band gap values up to 2.5 eV upon the insertion of transition metal copper (Cu) into the host lattice. Blue shift occurs due to Moss−Burstein effect upon excess concentration of Copper is realized. Both pristine and Cu doped Zn 2 SnO 4 present light green and dark blue colour upon the irradiation of different UV (252 nm and 365 nm) lamps, respectively. Besides this, Zn 2 SnO 4 shows effectiveness in hosting Cu ions, thus could act as a prospective green/blue emitter. [Display omitted] • Hydrothermal synthesis of Pristine and Cu doped Zn 2 SnO 4 nanostructures under subcritical conditions. • Band-gap reduction up to 2.5 eV upon 10% Cu doping is achieved. • 10% Cu doped Zn 2 SnO 4 shows the blue shift due to the Moss-Burstein Effect. • Theoretical modelling of electronic structure replicates the experimental data precisely. [ABSTRACT FROM AUTHOR]

Nanostructures that absorb wide range of visible light have the potential ability to combat wastewater problems by acting as visible light active photocatalysts. Ag 3 PO 4 nanostructures are visible light active and can address wastewater problems effectively. The present work explores the visible light activeness of the Ag 3 PO 4 nanostructures for photocatalysis of methylene blue (MB) dye by compositing it with zeolite-A also known as LTA (Linde Type A). Owing to strong adsorption performance and porosity of the LTA, we expect the resulting nanocomposite material to deliver best in the field of adsorption and catalysis. The zeolite-A and Ag 3 PO 4 @zeolite-A nanocomposite were synthesized by a facile hydrothermal and wet chemical strategy under normal conditions. The nano-photocatalysts were well characterized for their structural, morphological, compositional, optical, and photocatalytic applications. The structural study revealed the crystalline nature of the composite with the coexistence of the individual phase of Ag 3 PO 4 and the zeolite-A. The morphological investigation depicts the formation of 3D cubical structures having nanoscale dimensions, compositional analysis indicated the purity of the nanostructures consisting of only desired elements. The optical analysis revealed Ag 3 PO 4 as visible light active and zeolite-A as ultraviolet active material. In the case of Ag 3 PO 4 @zeolite-A, zeolite provides a large surface area for the adsorption of MB dye, and Ag 3 PO 4 acts as a principal visible light-absorbing material, to catalyze the degradation of MB dye. The composites prepared reduced the chances of charge recombination and inhibit the photo corrosion of the visible light active material Ag 3 PO 4. [Display omitted] • Ag 3 PO 4 is successfully decorated on zeolite-A with perfect cube like morphology. • 15% Ag 3 PO 4 composite is a promising photo-catalyst in visible region of sun light. • The composite was tested as a photo-catalyst for degradation of methylene blue. • The degradation process follows pseudo first order kinetics. [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO 2) and carbon nanofibers (CNF) based material have been widely used for supercapcitor, optoelectronic as well and electrochemical sensor applications due to their interesting physicochemical properties. Present article reports the facile hydrothermal synthesis of Sr–CeO 2 /CNF electrode material under subcritical reaction conditions. Different analytical techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV–Visible spectroscopy, X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), and Transmission electron microscopy (TEM) were used for the chractrization of nanocomposite. XRD and XPS results confirm the formation of Sr–CeO 2 /CNF having cubic fluorite structure. In addition, morphological studies shows formation of dot like morphology of Sr–CeO 2 nanoparticals embedded on CNF nanorods. Surface area analysis indicated that synthesized material is mesoporous in nature and exhibited high surface area of 38.45 m2/g. The optical absorption concludes that the band gap values lies between 2.1 and 3.15 eV, suitable for optoelectronic applications. Moreover, the electrochemical study of 5 wt% Sr–CeO 2 /CNF exhibits substantial specific capacitance of 192 Fg-1 with 95.4% good cyclic stability at 5000 cycles. The composite electrode exhibit energy density and power density of 96 WhKg−1and 1440 WKg−1at 0.8 Ag-1 current density suggesting a good electrode material for supercapacitor. Finally, the nanocomposite was also studied for cyclic voltammetric electrochemical detection of Harmaline (HAR) showing good sensitivity with Limit of detection (LOD) and Limit of quantification (LOQ) of 0.82 μg mL−1 and 2.48 μg mL−1 respectively. [ABSTRACT FROM AUTHOR]

In this paper, we report the fabrication of WO 3 nanostructures via hydrothermal route. This is the first report on pristine WO 3 nanoparticles being synthesized in a relatively short timed (4h) hydrothermal reaction. The obtained material was characterized in detail by a number of techniques: X-ray powder diffraction, scanning electron microscopy (SEM), optical studies, and Fourier transform analysis. From the observed results, these WO 3 nanoparticles exhibit a diameter approximately between 3 and 30 nm. Density functional theory calculations confirm the electronic band gap of 3.4 eV in accordance to experimental band gap obtained from optical absorption spectra. Cyclic voltammetry of the prepared WO 3 nanoparticles reveal the exhibition of remarkable electrochemical activity. In addition, the WO 3 particles were exposed to phenol and it was observed that 90.8% of phenol was degraded during the reaction time of 1.5 h. According to The International Commission on Illumination (CIE) the synthesized material shows blue emission and is suitable for blue LEDs. • Rapid synthesis of WO 3 nanostructures via hydrothermal route with a diameter of about 3–30 nm is achieved. • DFT calculations confirm the electronic band gap of 3.2 eV in accordance to experimental band gap. • Degradation of Phenol is observed up to 90% of Phenol during the reaction time of 1.5 h. [ABSTRACT FROM AUTHOR]

The present article reports the hydrothermal synthesis of quaternary Cu 2 MnSnS 4 (CMTS) nanostructures under subcritical reaction conditions. The effect of different chalcogen (sulfur) precursor sources (l -cysteine, elemental sulfur and sodium sulfide) on the growth and properties of the nanostructures is studied. The sulfur precursors showed prominent influence on the structural and morphological properties of the nanostructures. Structural properties indicated the growth of single phase crystalline materials. The crystal phase was controlled and determined by the reactivity of the sulfur sources. Metastable wurtzite phase was achieved with the mildly reactive precursor while tetragonal phase was obtained in the case of highly reactive precursors. Morphological studies showed formation of nanoflakes and anisotropic two-dimensional irregular nanostructures. Surface area analysis indicated that the nanoflakes are mesoporous in nature and exhibited a high specific surface area of 32.24 m2/g. The electrical studies demonstrated p-type conductivity of the material. Optical properties revealed optimum energy band gap value (~1.7 eV) of the nanostructures, suitable for the solar energy conversion applications. The magnetic properties indicated ferromagnetic behavior of the CMTS nanoflakes. The nanostructures were investigated as catalysts for photocatalytic decolaration of malachite green (MG) dye under UV–Visible light illumination. The nanoflakes showed good activity against the dye and photodegraded 95% of the dye in an illumination duration of 140 min. The photocatalysts exhibited good stability during the photocatalytic processes. [ABSTRACT FROM AUTHOR]

• Synthesis of sensor material by hydrothermal and Oxidative polymerization method and their characterization. • Fabrication of thin films by spin coating method on glass substrate. • Explanation of gas sensor setup and optimize the concentration in ppm for exposed gas. • Gas sensing study and proposed a most favorable mechanism on the bases of obtained results. • Explanation of stability and selectivity of the sensor. • Summery and conclusion. This work is an attempt to search for highly selective sensing material for 2-Chloroethyl ethyl sulfide (CEES, mustard gas simulant) vapors. Zeolite was modified with conducting polyaniline by the polymerization of anilinium cation. The nano composite of polyaniline/zeolite-Mor (Pani/Zeolite-Mor) was obtained by the chemical oxidative polymerization method. The polymer films and its composites with zeolite were used for detecting the toxic gas vapors. The sensing response of Pani and Pani/Zeolite-Mor was found to be 97.4 and 253.5 KΩ at 25 ppm of CEES. High sensing response of sensor was observed due to the zeolite framework, which provides greater pore volume and surface area. Pani/Zeolite-Mor sensor exhibited quick sensing response (11%) within 24 s at 25 ppm for CESS and relatively slower recovery (28.5 s) to the base line without heating. We also found that Pani/Zeolite-Mor show much higher response to CEES than NH 3 , ethanol and HCN due to the presence greater no of electronegative atom (high dipole moment value) in the molecular structure of CEES than ethanol and HCN. Our results demonstrated that Pani/Zeolite-Mor sensor was selective to CEES. During experiment 36% humidity and 31 ˚C (±2) temperature was recorded inside the gas chamber. Sensor shows good stability (2 months), low cost and easy to fabricate. All synthesized samples were characterized by using XRD, FT-IR, SEM-EDX, TGA-DTA and BET techniques. [ABSTRACT FROM AUTHOR]

Conductive polymers are gaining considerable attention as a potential material for supercapacitor electrodes due to their favorable properties. Among these, polyaniline (PANI) stands out as a cost-effective and easy to synthesize, making it a promising candidate for improving energy storage applications. This study presents the synthesis of a hybrid composite consisting of PANI and NiMnO 3 (NMO) perovskite using the chemical oxidative polymerization method. The morphology and structure of the composite were analyzed by using scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. XRD results showed that the addition of NMO transformed the amorphous structure of PANI into a semicrystalline form, leading to enhanced conductivity. SEM images revealed a more uniform and compact structure, with NMO distributed unevenly within the polymer matrix. Optical analysis indicated that a reduction in the band gap of PANI@NMO reached 2.5 eV. N 2 adsorption-desorption measurements confirmed an increase in the surface area and pore volume. The photocatalytic activity of the PANI@NMO nanocomposite was tested by degrading methylene blue (MB) dye under UV/visible light. The nanocomposite showed high efficiency, degrading 87.75% of MB dye after 125 min of irradiation as compared to their counter parts. Additionally, electrochemical tests demonstrated an improved electrochemical performance of the composite due to enhanced crystallinity, increased surface area, and reduced electron-hole recombination rate. These results suggest that the PANI@NMO nanocomposite has great potential for use in supercapacitors and photocatalysis.

Transition metal-based perovskites have emerged as highly promising and economically advantageous semiconductor materials due to their exceptional performance in optoelectronics, photovoltaic, photocatalysis, and photoluminescence. In this study, we employed a microwave-assisted hydrothermal process to produce a Cu-doped NiMnO 3 nanocomposite electrode material. The appearance of a peak corresponding to the (110) plane with a 2θ value of 36.6° confirmed the growth of the rhombohedral NiMnO 3 crystal structure. The presence of metal-oxygen bonds in NiMnO 3 was confirmed through FTIR spectra. XPS validates the chemical composition, providing additional support for the results obtained from XRD and FT-IR analyses. FE-SEM affirmed the anisotropic growth of small sphere-like structures that agglomerated to form broccoli-like shapes. Cu doping modified the band gap, reducing it from 2.2 to 1.7 eV and enhancing its photoluminescent (PL) activity by introducing defects. The increase in PL intensity (visible light luminescent intensity) can be attributed to a concurrent rise in complex defects and the rate of recombination of electron-hole pairs. Finally, the electrochemical activity demonstrated the pseudo-capacitor behavior of the synthesized material, with capacitance values increasing as the copper (Cu) content in the parent lattice increased., (© 2024. The Author(s).)

Mn doping in SrSnO 3 perovskite material via hydrothermal process under subcritical conditions is reported for the very first time. The present article aims to carry this perovskite suitable for blue light-emitting diodes (LEDs) and spintronic applications. The influence of various Mn doping percentages on structural, morphological, compositional, optical, photoluminescent, and magnetic properties of SrSnO 3 is demonstrated. The perovskite material is grown in an orthorhombic crystal structure having a space symmetry of Pnma along with point group of mmm as determined from the Rietveld refinement. Doping is an excellent way to modify the properties of wide-band-gap perovskite nanostructures. Incorporation of Mn is the result of exact substitution. Morphological studies indicate formation of rodlike structures with thickness in nanoscale dimensions (180-280 nm), and the thickness is a function of doping concentration. The higher doping concentration resulted in enhanced growth of the nanorods. Selected area electron diffraction (SAED) results showed the single-crystal nature of the nanorods. Thermogravimetric analysis (TGA) confirmed the high stability of the material at elevated temperatures. Also, the doped perovskite material is transparent in the visible light, active in the ultraviolet region having a band gap of ∼2.78 eV, and is tuned up to 2.25 eV as the Mn doping concentration reaches 10%. The transfer of excitonic energy from the host material to the dopant Mn 2+ ion leads to the formation of spin-forbidden [ 4 T 1 - 6 A 1 ] emission. Later on, photoluminescence study indicates an enhancement in luminescence behavior of Mn doped perovskite nanostructures. The Commission Internationale de l'éclairage (CIE) diagram drawn to find the color coordinates of the nanorods determines their suitability for blue LEDs. In addition, Mn doping results the conversion of diamagnetic SrSnO 3 into a ferromagnetic material, making the nanorods suitable for spintronic applications., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Chalcogenide nanostructures are the materials with diverse applications. Here, we report rapid hydrothermal synthesis of crystalline ZnSe quantum dots (QDs), avoiding the use of toxic chemicals. To the best of our knowledge, this is the first report on very rapid (5 h) hydrothermal synthesis of pristine ZnSe QDs. Elemental selenium is used as a source for selenium. Structural, morphological, compositional, and optical properties of the semiconductor were studied. Structural properties (X-ray diffraction) demonstrate that the particles have grown in a single cubic phase. Morphological studies show formation of agglomerated QDs (4 nm). The material possess stoichiometric ratio of the constituent elements that are uniformly distributed. Selected area electron diffraction (SAED) study indicated the material is polycrystalline in nature. Optical properties demonstrated that the QDs are suitable for optoelectronic devices exhibiting room temperature photoluminescence. Commission Internationale de l'Éclairage (CIE) chromaticity diagram shows the material exhibits violet emission and hence suitable for violet LEDs that have potential ability in clinical applications.

Sorption of As(III) has been studied on the synthesized gel close to Sodium potassium fluorophlogopite [Na0.5K0.5Mg3 (Si3 AlO10) F2] as a function of initial solution concentration at pH 2,4 and 7. The effect of parameters like equilibration time (0.5 - 24.0 hr), weight of the exchanger (30-150 mg) and temperature (25 degrees - 45 degrees c) has been investigated. The uptake of metal ion, As(III) has been expressed in terms of distribution coefficient i.e. (kd) values.