Synthesis,Characterization of Cr Doped TeO2 Nanostructures and its Application as EGFET pH Sensor

In the present work, Cr doped tellurium dioxide nanostructures (CTO NS)(1 wt %, 6 wt %, 8 wt % and 12 wt %) synthesized by co precipitation method and characterized by CV, UV-Visible, SEM, XRD, XPS spectroscopic analysis. Electron beam deposited thin film of CTO NS having 12 wt % of Cr exhibited EGFET-pH sensitivity of 62.03 mV/pH at 250 °C in buffer solutions of pH 6–12, linearity 0.9345, drift rate of 1.12 mV/h and deviation of 0.01145 as compared with 1 wt %, 6 wt % and 8 wt % of CTO NS.     

Enhanced photoluminescence properties of Gd (x-1) Sr x O: CdO nanocores and their study of optical,structural, and morphological characteristics

Synthesis of Gd doped Sr_x O: CdO (x = 1.4, 1.6, 1.8) nanostructures (NS) was achieved through the coprecipitation method by using CTAB (cetyl trimethyl ammonium bromide) with the purpose to investigate the effect of Gd doping on the optical, structural, morphological, and photoluminescence properties at room temperature. Mixed phase of tetragonal crystal structure verified via X-ray diffraction technique, no structural variation was observed except lattice distortion. Size of the crystallites (D), morphology studied by SEM (scanning electron microscopy) analysis, nanoparticles (NPs) crystalized roughly flake-like morphology with homogeneous particle distribution centered at ~ 78 nm, ~56 nm, ~65 nm, ~88 nm for pure and Gd _(x-1) doped Sr _xO: CdO nanostructure, respectively. Fourier transform infrared spectroscopic investigation (FTIR) revealed the presence of Gd–O–Gd, Cd–O, Sr–O, and OH peaks appeared at ~1321 cm ^?1, ~1550 cm ^?1, ~1400 cm ^?1–3300 cm ^?1 with small variation in vibration modes due to Gd doping. Optical absorptivity observed in the range of 325 nm–359 nm (redshifted) with absorption edges at 346 nm, 364 nm, and 380 nm for Gd _(x-1) doped Sr _xO: CdO nanostructure, respectively. This redshift on the bandgap was discussed in terms of new band levels below conduction band. The energy gap was calculated using Kubelka-Munk theory and was found to be in the range of 3.22 eV–2.61 eV. X-ray photoelectron spectroscopy (XPS) performed to determine chemical composition and binding energies of Gd 3d _3/2, Sr 3d _3/2, and Cd 3d _3/2, O1s, and C1s observed at 150.8 eV, 141.6 eV, 411.0 eV, 530.4 eV, and 285.6 eV indicating Gd⁺³ ion replaces Sr⁺² in all concentrations. Our results showed that Gd-doped Sr _xO: CdO nanoparticles exhibited enhanced photoluminescence (PL) properties in contrast to the pure Gd₂O₃ with Gd⁺³ randomly incorporated into crystal structure, probably in tetrahedral sites. The composition of Gd _0.6 doped Sr _x O: CdO NS exhibited photoluminescent emission spectra, peaks centered at 433 ± 3 nm, 449 ± 3 nm, and 469 ± 2 nm (λ _excitation = 318 nm) and for Gd _0.8 doped Sr _x O: CdO nanostructure showed broad emission peak at 412 ± 2 nm to 433 ± 2 nm (λ _excitation = 380 nm), which indicates a reduction in defects with an increase in Gd doping. The transitions can be ascertained with shielding of 4f shells of Gd ⁺³ ions by 6s, 5d shells by the interaction of other Gd ⁺³ ions.     

Synthesis,crystal structure and molecular docking studies of novel 2-(4-(4-substitutedphenylsulfonyl)piperazin-1-yl)quinolone-3-carbaldehyde derivatives

The present work reports the synthesis of novel 2-(4-(4-substitutedphenylsulfonyl) piperazin-1-yl) quinolone-3-carbaldehyde derivatives, namely, 2-(4-tosylpiperazin-1-yl)quinoline-3-carbaldehyde (4a), 2-(4-(4-nitrophenylsulfonyl)piperazin-1-yl)quinoline-3-carbaldehyde (4b) and 2-(4-(4-tert-butylphenylsulfonyl) piperazin-1-yl)quinoline-3-carbaldehyde (4c). These compounds have been characterized by FT-IR, ¹H-NMR, ¹³C-NMR and LCMS. Further, the structures of compounds 4b and 4c have been elucidated by single crystal X-ray diffraction studies. The asymmetric unit of 4b contains two molecules (A and B) and that of 4c contains one. The piperazine ring in both the molecules 4b and 4c has chair conformation and the aldehyde group is twisted with respect to the quinoline group, respectively, by 13.3 (3)°, 18.2 (3)° and 11.2 (3)° in Molecule A & B of 4b and 4c due to the bulky piperazinyl group present in the ortho position. The crystal structures of both features interactions of the type C-H…O, C-H…π_aryl and π_aryl… π_aryl, leading to a three-dimensional (3D) supramolecular architecture in 4b and a one-dimensional (1D) architecture in 4c. The various intermolecular interactions exhibited in 4b and 4c are well supported by Hirshfeld surface and fingerprint plots analysis. Further, the three compounds were evaluated for their in-silico antimicrobial activity. In-silico molecular docking studies were carried out in order to know the binding modes of the synthesized compounds with DNA Gyrase A and N-myristoyltranferase as target proteins for antibacterial and antifungal docking studies, respectively.     

MgSiO3 NPs catalyzed intramolecular cycloaddition reaction: A simple and stereoselective synthesis of unprecedented julolidine analogs

A new julolidine hybrid analogs have been accomplished in a regio and stereo controlled manner using heterogenous MgSiO₃ nanoparticles (NPs) catalyzed intramolecular dipolar cycloaddition reaction as a key step. The synthesized catalyst was used in the preparation of various new julolidine analogs with a good yield ranging from 65 to 85%. Further, catalyst could be recycled in several times without loss of significant activity which was an added advantage to the principles of green chemistry.     

Synthesis,characterization, X-ray diffraction studies and biological evaluation of tert-butyl 4-(2-ethoxy-2-oxoethyl)-piperazine-1-carboxylate and tert-butyl 4-(2-hydrazino-2-oxoethyl)piperazine-1-carboxylate

Two derivatives of N-Boc piperazine, an ester derivative, i.e., tert-butyl 4-(2-ethoxy-2-oxoethyl)-piperazine-1-carboxylate (1), and, a hydrazide derivative tert-butyl 4-(2-hydrazino-2-oxoethyl)piperazine-1-carboxylate (2) were synthesized and were characterized by FT-IR, ¹H & ¹³C NMR and LCMS spectroscopic studies. The structures of both 1 and 2 were further confirmed by single crystal X-ray diffraction analysis. The molecule of 1 is linear in shape with the ethyl acetate moiety adopting fully extended conformation, while the molecule of 2 is L-shaped with the molecule being twisted at the C10 atom. The crystal structure of 1 adopts a two-dimensional zig-zag architecture featuring C–H…O intermolecular interactions, while that of 2 features strong N–H…O hydrogen bonds and intermolecular interactions of the type N–H…N and C–H…N, resulting in a two-dimensional structure. Furthermore, a detailed analysis of the intermolecular interactions and crystal packing of 1 and 2 via Hirshfeld surface analysis and fingerprint plots was performed. The antibacterial and antifungal activities of both the compounds have been studied against several microorganisms, and were found to be moderately active.     

Enhanced electrical properties of CuO:CoO decorated with Sm2O3 nanostructure for high-performance supercapacitor

Journal of Solid State Electrochemistry - In the present investigation, we have synthesized samarium (Sm) nanoparticles (NPs) and anchored them onto the surface of CuO:CoO nanostructure (NS) by...