Chemistry of Inorganic Materials最新文献

Environmental remediation is challenged by the removal of harmful heavy metal contaminants from industrial waste streams. Because of its low cost and great effectiveness, adsorption is a commonly used separation method, particularly in environmental cleanup. Inexpensive, biodegradable orange peel-chitosan and Fe₃O₄ magnetic particles (Fe₃O₄-OP-CS) were combined in a simple process to create an innovative composite. Their structure and morphology were studied using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analyses. At room temperature, adsorption experiments were conducted, and variables such pH, initial metal ion concentration, and contact time were tuned to maximize Cd(II) removal. The results of harmful Cd(II) sorption using the synthesized composite showed that its adsorption kinetics and sorption isotherm confirm to the pseudo-second-order and Langmuir models, respectively. The thermodynamic analysis showed that Cd(II) adsorption is exothermic and spontaneous. In comparison to previously reported materials, the new composite also displayed a high adsorption capacity (qmax) of 251.88 mg/g. The composite showed three cycles of reuse and might still be able to promise a maximum saturated adsorption capacity of more than 92%, and tolerance to related metal ions (Mn, Fe, Pb, and Cr) present in Cd (II). In addition to Cd(II) sorption for preconcentration and remediation before Cd testing from waste, digested tobacco, and battery samples, the proposed method is also credible for Cd(II) sorption.

Inorganic lead halide perovskites have appeared as favorable and novel materials for their effective use in photovoltaics. The synthesis route of such materials via the simple wet chemistry technique renders these inorganic halide perovskites the ideal property for light-harvesting materials. Despite these novel properties, the inherently unstable nature under increased heat and ambient moisture conditions is still a conjecture that needs to be addressed. This work shows the wet chemistry method as a synthesis route of the novel RbPbCl₃ perovskite using four different solvents for photovoltaic applications. Interestingly, the synthesized perovskite was stable in only one solvent with a band gap of 2.6 eV, whereas the material degraded in the other three. The DFT calculations performed post-geometric optimization revealed well-defined electronic bandgap and optical properties, nearly imitating the experimental data of our synthesized perovskite. The copious properties such as electronic, optical, and formation energy revealed that the perovskite possesses huge charge screening ability, a low recombination rate of electron-hole pairs, board absorption spectrum, and high stability. Henceforth, establishes its suitability for photovoltaic devices. The close fit of the experimental results with our theoretical trend demonstrates the importance of developing a computational strategy to screen for new perovskite materials for photovoltaic cells.

Water pollution by contaminants such as dyes and drugs is a serious environmental problem. Currently, the objective is to develop materials that are effective in removing these contaminants. Graphene oxide (GO) and graphitic carbon nitride (g-C₃N₄) have been used as adsorbents for the efficient removal of organic pollutants and are useful to improve the photoactivity of iron oxide (Fe₃O₄). In this work, the Fe₃O₄, Fe₃O₄–C₃N₄, Fe₃O₄–GO, and Fe₃O₄–GO–C₃N₄ powders were structurally characterized by the X-ray diffraction technique and morphologically by the field emission scanning electron microscopy technique. Optical properties were studied using UV–visible spectroscopy and VSM analysis was performed to determine the remanence magnetization. The adsorption and photocatalysis were tested against methylene blue (MB), methyl orange (MO) and ketoprofen. XRD patterns for Fe₃O₄ and heterojunctions showed Fe₃O₄ formed as a single phase. As for morphological observation, Fe₃O₄ and g-C₃N₄ are formed by nanoparticles without defined morphology, while GO is formed by sheets. As for the VSM analysis, all samples show ferromagnetic behavior. The Fe₃O₄, Fe₃O₄–C₃N₄, Fe₃O₄–GO, and Fe₃O₄–GO–C₃N₄ samples have a bandgap of 2.07, 2.21, 2.14, and 2.19 ​eV, respectively. Therefore, all samples absorb visible radiation in waves greater than 560 ​nm. Heterojunctions containing g-C₃N₄ completely adsorb the MB and MO dyes, being necessary to extend the activity time when concentration increases or when the dyes are put together. Both Fe₃O₄ and Fe₃O₄–GO have photocatalytic properties toward MO dye. All materials studied in this manuscript have good adsorption and photocatalytic capacity against the anti-inflammatory drug ketoprofen.

In this study, a modified carbon paste electrode with silver particles (Ag–CPE) was used for ofloxacin (OFL) detection with enhanced over-potential for low concentrations. The incorporation of silver particles on carbon paste was confirmed by scanning electron microscopy. Electrochemical behavior of ofloxacin at carbon paste electrode (CPE) and Ag–CPE was studied using cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The OFL interaction with Ag⁺ was derived from the oxidation of silver during anodic scan has been investigated under different conditions. The strong binding affinity of Ag⁺ with 1.0 ​× ​10⁻⁵ ​M OFL resulted in the upward shift of the OFL potential, which shifted potential from 0.85 to 0.95 ​V. The modification of carbon paste electrode by silver microparticles has enhanced the oxidation current with over-potential of OFL at low concentrations without a decrease of the current. The influence of the sweeping potential range on OFL oxidation was optimized. The calibration curve for ofloxacin at Ag–CPE is linear in the range from 4.0 ​× ​10⁻⁶ to 1.0 ​× ​10⁻³ ​M, and the detection limit was 9.47 ​× ​10⁻⁷ ​M. Possible effects of inorganic ions and organic substances were investigated but did not cause any significant interferences. Furthermore, the repeatability, reproducibility, and stability of the present sensor were done with satisfactory results. The proposed method was successfully applied to OFL determination in tap water samples.

Schiff-base fluorescent chemosensor (E)-N-(4-(dimethylamino)benzylidene)quinolone-3-amine (DBQA) was synthesized and characterized by FT-IR,¹H NMR,¹³C NMR, ESI-MS spectrometry and Single X-ray crystallographic studies. The synthesized chemosensor (DBQA) was used for the detection of Fe³⁺ successfully. UV-visible and fluorescence spectra of (DBQA) exhibits a ratiometric behaviour along with a bathochromic shift upon the successive addition of Fe³⁺. The fluorescence spectra of chemosensor (DBQA) were recorded followed by addition of concentrations of different metal ions and NH₃. The chemosensor (DBQA) showed a favourable linear relationship between the fluorescence intensity and concentration of Fe³⁺ ion. DBQA exhibits a ratiometric response and illustrates high sensitivity (with a detection limit of 0.4 ​μM) and good selectivity for the Fe³⁺ ion over other transition metal ions. DBQA shows 0.6 ​μM detection limit for NH₃ along with ratiometric behaviour also. The association constant (K_a) of chemosensor (DBQA) was found to be 1.455×10² ​M^-1/2 for Fe³⁺. The mechanism of sensing of the present ratiometric fluorescent chemosensor (DBQA) was explained by ICT (Intra-molecular charge transfer) using DFT calculations. The interaction model of chemosensor (DBQA) with Fe³⁺ was determined to be 2:1 stoichiometry using Job's plot analysis and ESI-MS spectra which further confirms DFT studies. Moreover, tested DBQA ​+ ​Fe³⁺ was showed that remarkable anticancer activity against the HCT116 colon cancer cells by MTT assay. Novelty and importance of DBQA as it can be investigate, test or analyse of detect Fe³⁺ rapidly as compared to other tested ions. Lastly, DBQA can be investigate, test or analyse of Fe³⁺ in environmental and biological samples.

SnO₂ offers compelling advantages as an excellent electron transport layer material in perovskite solar cells. However, the defects caused by oxygen vacancies are unfavorable to the interface contact and would hinder the device performance. A simple and effective interface passivation strategy using 3-Hydroxytyramine hydrochloride (3-Hh) is developed, which realizes the bidirectional passivation of electron transport layer and perovskite. The passivation mechanism of 3-Hh is investigated. Further, the morphology of the subsequent deposited perovskite film is improved. The modified perovskite film exhibits increased grain size with better uniformity, reduced grain boundaries, lowered defect density. A relatively higher power conversion efficiency of 22.63% is achieved for the perovskite solar cells based on the bidirectional passivation of SnO₂/perovskite interface. Meanwhile, the modified devices can retain 80% and 82% of the initial efficiency after storage for 1400 ​h in air and 700 ​h in 85 ​°C, respectively. The results show that 3-Hh could be a promising multifunctional interface material to further enhance the efficiency and the stability of perovskite solar cells.

Self-compaction concrete is huge flow capable kind of concrete that flows through the appearance lacking of any shaking. Self-compacting concrete is a non-separating concrete those can be located by its own mass. It has fresh properties approximately passing capacity, flowing ability, filling ability and segregate resistance which can be estimated by conducting workability tests like L-Box, V-Funnel, U-Box, J-Ring and Slump cone flow. The characteristics of self-compacting concrete replacing by fly ash to improved the fresh state stability, rheological properties and compressive strength and steel fibers generating a highest compression and splitting tensile strengths in self-compaction concrete. The effects of fly ash as 5%, 10%, 15%, 20%, 25%, 30% weight of cement and of steel fibers as 0.5%, 1.0%, 1.5, 2% with taking of the highest (optimum) value of fly ash to get maximum strength. The strength characteristics like compression, split, tensile and flexural strengths. And longevity (durability) properties like sorpitivity, rapid chloride permeability test (RCPT) of self-compacting concrete.

Three Pd(II) complexes of Schiff bases such as 2-((6-chloro-4-oxo-4H-chromen-3-yl)methyleneamino)-1H-imidazole-5(4H)-one (L1), 2-((1H-indol-3-yl)methyleneamino)-1H imidazole-5(4H)-one (L2) & 2-(thiophen-2-ylmethyleneamino)-1H-imidazole-5(4H)-one (L3) have been synthesized and characterized by analytical and spectroscopic techniques like, ¹H and ¹³C NMR, IR, UV–Vis. ESI-Mass etc. The anti-diabetic activities of both ligands and complexes were examined by α-amylase and α-glucosidase assay using acarbose as standard drug. As a result the complexes (L1)₂Pd and (L2)₂Pd exhibited a strong inhibition against α-amylase (IC50 ​= ​136.0 ​μg/ml and 167.8 ​μg/ml) and α-glucosidase (IC50 ​= ​97.34 ​μg/ml and 128.5 ​μg/ml) respectively. The molecular energy levels calculation were performed by Gaussian 09 program by Density Functional Theory (DFT) using B3LYP/6-31G∗ basis set. Molecular docking disquisition was carried out using Molecular operation environment software (MOE) indicate as finest positioned in the essential sites of receptor having docking scores −6.96 and −7.72 respectively for (L2)₂Pd and (L3)₂Pd. ADME predictions also carried for the compounds L1, L2 and L3. All the ligands were obeyed the Lipinski's rule of five and also in the acceptable range. By using the Agar well diffusion method, the antibacterial and antifungal properties of the label compounds were investigated.

In this study, the effect of DC corona poling on the photocatalytic degradation response of conventional ferroelectric BaTiO₃ nanoparticles over the methyl-violet and rhodamine B dyes has been investigated systematically. The BaTiO₃ (BT) nanoparticles were synthesized via modified sol-gel route. The synthesized BT nanoparticles were characterized by using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX), P-E hysteresis loop, impedance analyzer, photoluminescence spectroscopy and UV–vis spectroscopy. X-ray diffraction (XRD) and Raman spectroscopy confirmed the tetragonal phase of BT nanoparticles. The average particle size was found to be 130 ​nm as confirmed by SEM. The P-E hysteresis loop confirmed the ferroelectric nature of the sample and the T_c was observed nearly 130 ​°C as confirmed by dielectric study. The optical bandgap was found to be 3.74 ​eV and 3.49 ​eV for unpoled and poled samples, respectively. The degradation efficiency of the corona poled and unpoled BaTiO₃ samples for the rhodamine dye solution was 45% and 25%, respectively, whereas it was 93% and 83% for methyl violet dye solution in 120 ​min under UV–vis light. The corona poling enhanced the alignment of electric dipoles in BaTiO₃, which causes higher spatial charge separation, lowering the electron-hole recombination and hence improved the degradation efficiency.

Based on density functional theory (DFT) approach, investigations on the structural, thermodynamic, electronic, optoelectronic, phonon, mechanical, and the hydrogen gravimetric storage density of CsSnX₃ (X ​= ​O, S, Se and Te) perovskite systems is presented herein. While results of the computed lattice constant values for the investigated perovskite systems increased with an increase in the size of the anion X (X ​= ​O, S, Se, Te), the electronic bandgap values of 1.42, 1.02, 0.64, and 0.40 ​eV is obtained for CsSnO₃, CsSnS₃, CsSnSe₃, and CsSnTe₃ respectively. Among the studied systems, CsSnO₃ and CsSnS₃ are found to be dynamically stable, with CsSnO₃ material being the most stable among the studied compounds owing to its frequencies in the real state of the phonon dispersion curve. To study the hydrogen storage properties of the materials in this present study: CsSnO₃, CsSnS₃, CsSnSe₃, and CsSnTe₃ the crystal structures have been modified by replacing the heteroatoms (O, S, Se, and Te) with hydrogens which is given as: CsSnO_H₄, CsSnS_H₄, CsSnSe_H₄ and CsSnTe_H₄. The gravimetric density (GD) suggests a strong agreement with the calculated band structure and decreases as the amount of band gap becomes enormous, where the CsSnO reveals a highest capacity of 0.74 which decrease as we go from O–Te for two atomic hydrogens. The CsSnTe shows the lowest gravimetric density of 0.526. Also, the formation energies obtained for CsSnO_{3_}H₄ estimated to be −31.599 ​kJ ​mol⁻¹ ​has the highest energy however, these was observed to decrease as we go from oxygen to S ​> ​Se ​> ​Te. Moreover, the desorption temperature which is necessary for physical application reveals that the investigated materials are in line with the required range of desorption temperature for practical applications 289 ​K ​°K proposed by US-DOE, which implies that there are no barriers for hydrogen desorption from CsSnX_{3_}H₄ compounds. Therefore, it can be deduced that CsSnX_{3_}H₄ is a reversible hydrogen storage material. However, CsSnO_{3_}H₄ the best desorption temperature, this means that the presence of O atom in the perovskite improves the adsorption energy of interaction between the crystal lattice and the hydrogen molecules and decrease in the order of S ​> ​Se ​> ​Te respectively.