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Herein we have reported a fluorescent probe (MB-M) based on MB derivative for Cu2+ ions detection. The probe was well characterized by 1H NMR, 13C NMR and HR-MS spectrum. Probe MB-M showed naked-eyes recognition to Cu2+ as color change from colorless to indigo. The probe exhibited promising features such as high fluorescence and UV-vis selectivity, fast response (5 mint), workable at pH 2-7, and low limit of detection (LOD = 0.33 µM). Probe MB-M was also used for Cu2+ ions imaging in HepG-2 cells and detection in daily life (Test Strip and lake water). Moreover, non-covalent interaction (NCI) and quantum theory of atoms in molecules (QTAIM) analysis were used to study the interaction between MB-M and Cu2+ ions. By examining the electronic characteristics of the complex using natural bond orbital (NBO), electron density difference (EDD), and frontier molecular orbital (FMO) analysis, the sensitivity of MB-M towards Cu2+ ions were investigated. The results illustrated that the interactions between MB-M and Cu2+ ions involved chemisorption.
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Cobre , Corantes Fluorescentes , Cobre/análise , Cobre/química , Corantes Fluorescentes/química , Humanos , Células Hep G2 , Imagem Óptica/métodos , Íons , Espectrometria de Fluorescência/métodos , Limite de DetecçãoRESUMO
Cerium-based Metal-Organic frameworks (Ce-MOFs) are attracting increasing interest due to their similar structural features to zirconium MOFs. The redox behavior of Ce(III/IV) adds a range of properties to the compounds. Recently, perfluorinated linkers have been used in the synthesis of MOFs to introduce new characteristic into the structure. We report the synthesis and structural characterization of Ce(IV)-based MOFs constructed using two perfluorinated alkyl linkers. Their structure, based on hexanuclear Ce6O4(OH)4 12+ clusters linked to each other by the dicarboxylate ions, has been solved ab-initio from X-ray powder diffraction data and refined by the Rietveld method. The crystallization kinetics and the MOF formation mechanism was also invesitigated by Synchrotron radiation with XAS spectroscopies (EXAFS and XANES). The MOFs present the same fcu cubic topology as observed in MOF-801 and UiO-66, and they showed good stability in water at different pH conditions. The electronic structure of these MOFs has been studied by DFT calculations in order to obtain insights into the density of states structure of the reported compounds, resulting in band gaps in the range of 2.8-3.1â eV. Their catalytic properties were tested both thermally and under visible light irradiation for the degradation of methyl orange (MO) dye.
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The focus of this paper is laid on synthesizing layered compounds of CuMoO4 and Ti3C2Tx using a simple wet chemical etching method and sonochemical method to enable rapid detection of rutin using an electrochemical sensor. Following structural examinations using XRD, surface morphology analysis using SEM, and chemical composition state analysis using XPS, the obtained CuMoO4/Ti3C2Tx nanocomposite electrocatalyst was confirmed and characterized. By employing cyclic voltammetry and differential pulse voltammetry, the electrochemical properties of rutin on a CuMoO4/Ti3C2Tx modified electrode were examined, including its stability and response to variations in pH, loading, sweep rate, and interference. The CuMoO4/Ti3C2Tx modified electrode demonstrates rapid rutin sensing under optimal conditions and offers a linear range of 1 µΜ to 15 µΜ, thereby improving the minimal detection limit (LOD) to 42.9 nM. According to electrochemical analysis, the CuMoO4/Ti3C2Tx electrode also demonstrated cyclic stability and long-lasting anti-interference capabilities. The CuMoO4/Ti3C2Tx nanocomposite demonstrated acceptable recoveries when used to sense RT in apple and grape samples. In comparison to other interfering sample analytes encountered in the current study, the developed sensor demonstrated high selectivity and anti-interference performance. As a result, our research to design of high-performance electrochemical sensors in the biomedical and therapeutic fields.
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Antioxidantes , Nanocompostos , Titânio , Cromatografia Gasosa , RutinaRESUMO
Zinc sulfide/graphitic Carbon Nitride binary nanosheets were synthesized by using a novel sonochemical pathway with high electrocatalytic ability. The as- obtained samples were characterized by various analytical methods such as Transmission Electron Microscopy (TEM), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS) to evaluate the properties of ZnS@CNS synthesized by this new route. Subsequently, the electrical and electrochemical performance of the proposed electrodes were characterized by using EIS and CV to establish an electroactive ability of the nanocomposites. The complete properties like structural and physical of ZnS@CNS were analyzed. As-prepared binary nanocomposite was applied towards the detection of anticancer drug (flutamide) by various electrochemical methods such as cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometry. The glassy carbon electrode modified with a ZnS@CNS composite demonstrates a remarkable electrocatalytic efficiency for detecting flutamide in a pH 7.0 (PBS). The composite modified electrode shows synergistic effect of ZnS and CNS catalyst. The electrochemical sensing performance of the linear range was improved significantly due to high electroactive sites and rapid electron transport pathways. Crucially, the electrochemical method was successfully demonstrated in biological fluids which reveals its potential real-time applicability in the analysis of drug.
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Antineoplásicos , Eletrodos , Grafite , Compostos de Nitrogênio , Sulfetos , Ondas Ultrassônicas , Compostos de Zinco , Compostos de Zinco/química , Sulfetos/química , Antineoplásicos/química , Grafite/química , Flutamida/análise , Flutamida/química , Técnicas Eletroquímicas/métodos , Técnicas de Química Sintética , Eletroquímica , Limite de Detecção , Catálise , Nanocompostos/química , Nanoestruturas/químicaRESUMO
Chemical environment and precursor-coordinating molecular interactions within a perovskite precursor solution can lead to important implications in structural defects and crystallization kinetics of a perovskite film. Thus, the opto-electronic quality of such films can be boosted by carefully fine-tuning the coordination chemistry of perovskite precursors via controllable introduction of additives, capable of forming intermediate complexes. In this work, we employed a new type of ligand, namely 1-phenylguanidine (PGua), which coordinates strongly with the PbI2 complexes in the perovskite precursor, forming new intermediate species. These strong interactions effectively retard the perovskite crystallization process and form homogeneous films with enlarged grain sizes and reduced density of defects. In combination with an interfacial treatment, the resulted champion devices exhibit a 24.6% efficiency with outstanding operational stability. Unprecedently, PGua can be applied in various PSCs with different perovskite compositions and even in both configurations: n-i-p and p-i-n, highlighting the universality of this ligand.
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Magnetic spinel ferrite nanoparticles (MSF-NPs) are potential candidates for biomedical applications, especially in cancer diagnosis and therapy due to their excellent physiochemical and magnetic properties. In the current study, MSF-NPs were fabricated by sol-gel auto combustion method. The crystal structure and surface morphology were confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The magnetic properties were studied by VSM (vibrating sample magnetometer). As increasing Gd3+ concentration, the saturation magnetization values decreased from (17.8-2.3) emu/g, while the coercivity decreased from (499-133) Oe at room temperature. Finally, the fabricated MSF-NPs were tested against anticancer activity by MTT assay. The IC50 = 21.27 µg/mL value was observed, showing the strong antiproliferative activity of these nanoparticles. These results suggested that the obtained MSF-NPs would be useful for remote-controlled hyperthermia therapy for cancer treatment and MRI application due to their excellent magnetic properties. These distinct properties make MSF-NPs most suitable for cancer treatment and bright Contrast Agents (T1-MRI).
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Over the past decade, perovskites have received considerable attention because of their record power conversion efficiency (25.7%) in solar cells. These materials have also received recent research interest in thermoelectrics, most likely due to their high carrier mobility, large power factor, and ultralow thermal conductivity. Therefore, in the present work, we have examined the optoelectronic and thermoelectric properties of A2NaIO6 (A = Ca, Sr) double perovskites using first-principles calculations. Stability has been confirmed using reliable and accurate descriptors of formation energy and phonon calculations. The optimized lattice constant and volume show an increasing tendency with changing A site cation (Ca â Sr). The computed band structures depict the semiconducting nature with direct band gap values of 2.64 eV (Ca2NaIO6) and 2.48 eV (Sr2NaIO6). The absorption was found to start in the visible range where the reflectivity was less than 10%. Moreover, the high Seebeck coefficient, large electrical conductivity, and fairly low thermal conductivity result in ZT values of 0.724 for Ca2NaIO6 and 0.686 for Sr2NaIO6 at 1000 K. With their optimum band gap, excellent light absorption capacity, and high ZT values, A2NaIO6 emerge as promising candidates for optoelectronic and thermoelectric applications.
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Ti3C2-MXene material, known for its strong electronic conductivity and optical properties, has emerged as a promising alternative to noble metals as a cocatalyst for the development of efficient photocatalysts used in environmental cleanup. In this study, we investigated the photodegradation of crystal-violet (CV) dye when exposed to UV light using a newly developed photocatalyst known as Ti3C2-MXene/NiO nanocomposite-decorated CsPbI3 perovskite, which was synthesized through a hydrothermal method. Our research investigation into the structural, morphological, and optical characteristics of the Ti3C2-MXene/NiO/CsPbI3 composite using techniques such as FTIR, XRD, TEM, SEM-EDS mapping, XPS, UV-Vis, and PL spectroscopy. The photocatalytic efficacy of the Ti3C2-MXene/NiO/CsPbI3 composite was assessed by evaluating its ability to degrade CV dye in an aqueous solution under UV-light irradiation. Remarkably, the Ti3C2-MXene/NiO/CsPbI3 composite displayed a significant improvement in both the degradation rate and stability of CV dye when compared to the Ti3C2-MXene/NiO nanocomposite and CsPbI3 perovskite materials. Furthermore, the UV-visible absorption spectrum of the Ti3C2-MXene/NiO/CsPbI3 composite demonstrated a reduced band gap of 2.41 eV, which is lower than that of Ti3C2-MXene/NiO (3.10 eV) and Ti3C2-MXene (1.60 eV). In practical terms, the Ti3C2-MXene/NiO/CsPbI3 composite achieved an impressive 92.8% degradation of CV dye within 90 min of UV light exposure. We also confirmed the significant role of photogenerated holes and radicals in the CV dye removal process through radical scavenger trapping experiments. Based on our findings, we proposed a plausible photocatalytic mechanism for the Ti3C2-MXene/NiO/CsPbI3 composite. This research may open up new avenues for the development of cost-effective and high-performance MXene-based perovskite photocatalysts, utilizing abundant and sustainable materials for environmental remediation.
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Herein, nanostructured Gd-doped ZnFe2O4 (GZFO) has been synthesized via the sol-gel route and its CNT-reinforced nanohybrid was formed via an advanced ultrasonication method. The as-synthesized, hybrid electroactive materials have been supported on aluminum foil (AF) to design a flexible electrode for hybrid capacitor (HC) applications. Nanostructured material synthesis, Gd-doping, and CNT reinforcement approaches have been adopted to develop a rationally designed electrode with a high surface area, boosted electrical conductivity, and enhanced specific capacitance. Electrochemical impedance spectroscopy, galvanostatic charge/discharge, and cyclic voltammetry processes have been used to measure the electrochemical performance of the prepared ferrite material-based working electrodes in a 3M KOH solution. A nanohybrid-based working electrode (GZFO/C@AF) shows superior rate capacitive and electrochemical aptitude (specific capacitance, rate performance, and cyclic activity) than its counterpart working electrodes (ZFO@AF and GZFO@AF). The hybrid working electrode (GZFO/C@AF electrode) shows a high specific capacitance of 887 F g-1 and good retention of 94.5% for 7000 cycles (at 15 Ag-1). The maximum energy density and power density values for the GZFO/C@AF electrode are 40.025 Wh Kg-1 and 279.78 W Kg-1, respectively. Based on the findings of the electrochemical experiments, GZFO/C@AF shows promise as an electrode material for hybrid capacitors that provide energy to wearable electronic devices.
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Preconcentration for on-site detection or subsequent determination is a promising technique for selective sensing explosive markers at low concentrations. Here, we report divinylbenzene monolithic polymer in its blank form (neat-DVB) and as a composite incorporated with sodalite topology zeolite-like metal-organic frameworks (3-ZMOF@DVB), as a sensitive, selective, and cost-effective porous preconcentrator for aliphatic nitroalkanes in the vapor phase as explosive markers at infinite dilution. The developed materials were fabricated as 18 cm gas chromatography (GC) monolithic capillary columns to study their separation performance of nitroalkane mixture and the subsequent physicochemical study of adsorption using the inverse gas chromatography (IGC) technique. A strong preconcentration effect was indicated by a specific retention volume adsorption/desorption ratio equal to 3 for nitromethane on the neat-DVB monolith host-guest interaction, and a 14% higher ratio was observed using the 3-ZMOF@DVB monolithic composite despite the low percentage of 0.7 wt.% of sod-ZMOF added. Furthermore, Incorporating ZMOF resulted in a higher percentage of micropores, increasing the degree of freedom more than bringing stronger adsorption and entropic-driven interaction more than enthalpic. The specific free energy of adsorption (ΔGS) values increased for polar probes and nitroalkanes, denoting that adding ZMOFs earned the DVB monolithic matrix a more specific character. Afterward, Lewis acid-base properties were calculated, estimating the electron acceptor (KA) and electron donor (KB) constants. The neat-DVB was found to have a Lewis basic character with KB/KA = 7.71, and the 3-ZMOF@DVB had a less Lewis basic character with KB/KA = 3.82. An increased electron-accepting nature can be directly related to incorporating sod-ZMOF into the DVB monolithic matrix. This work considers the initial step in presenting a portable explosives detector or preconcentrating explosive markers trace prior to more sophisticated analysis. Additionally, the IGC technique allows for understanding the factors that led to the superior adsorption of nitroalkanes for the developed materials.
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Substâncias Explosivas , Estruturas Metalorgânicas , Zeolitas , Polímeros , Alcanos , Bases de LewisRESUMO
The pad dry cure method was used to coat linen fibers with a smart nanocomposite that has photoluminescence, electrical conductivity, flame resistance, and hydrophobic properties. Environmentally benign silicone rubber (RTV) was utilized to encapsulate rare-earth activated strontium aluminate nanoparticles (RESAN; 10-18 nm), polyaniline (PANi) and ammonium polyphosphate (APP) into linen surface. The flame resistance of the treated linen fabrics was evaluated for their self-extinguishing capabilities. The flame-retardant qualities of linen were retained for 24 washings. Additionally, the superhydrophobicity of the treated linen has markedly improved upon increasing the concentration of RESAN. The colorless luminous film deposited onto linen surface was excited at 365 nm and emitted a wavelength of 518 nm. In accordance with the results of CIE (Commission internationale de l'éclairage) Lab and luminescence analysis, the photoluminescent linen gave rise to diverse colors, including off-white in daylight, green beneath UV radiation and greenish-yellow in a darkened room. The treated linen displayed sustained phosphorescence, as evidenced by decay time spectroscopy. The bending length and air permeability of linen were evaluated for their mechanical and comfort assessment. Finally, the coated linens exhibited remarkable antibacterial activity along with strong UV protection.
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Retardadores de Chama , Nanocompostos , Celulose/química , Estrôncio , Nanocompostos/química , Condutividade ElétricaRESUMO
In the current study, cellulose/MoS2/GO nanocomposite has been synthesized by a hydrothermal method. Reports published regarding efficiency of Mo and graphene oxide-based nanocomposites for environmental remediation motivated to synthesize cellulose supported MoS2/GO nanocomposite. Formation of nanocomposite was initially confirmed by UV-visible and FTIR spectroscopic techniques. Particle size and morphology of the nanocomposite were assessed by scanning electron microscopy (SEM), and it was found having particle size ranging from 50 to 80 nm and heterogeneous structure. The XRD analysis also confirmed the structure of the nanocomposite having cellulose, MoS2, and GO. The synthesized nanocomposite was further tested for biomolecule protective potential employing different radical scavenging assays. Results of radical DPPHâ (50%) and ABTS â+ (51%) scavenging studies indicate that nanocomposites can be used as a biomolecule protective agent. In addition, nanocomposite was also evaluated for photocatalytic potential, and the results showed excellent photocatalytic properties for the degradation of 4-nitrophenol up to 75% and methylene blue and methyl orange up to 85% and 70%, respectively. So, this study confirmed that cellulose supported/stabilized MoS2/GO nanocomposite can be synthesized by an ecofriendly, cost-effective, and easy hydrothermal method having promising biomolecule protective and photocatalytic potential.
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This work successfully utilised eco-friendly green synthesis to produce Ag-TiO2 nanofibers (NFs). As pollution and energy limitations have become global issues, there is an ongoing need to develop more effective catalysts through straightforward and environmentally friendly methods. The Ag-TiO2 nanofibers (NFs) XRD pattern exhibits an anatase TiO2 and FCC crystal structure of Ag nanoparticles. The SEM investigation revealed a nanofiber-like surface morphology. The Ag-TiO2 nanofibers (NFs) exhibits an optical band gap energy is 2.5 eV. Methylene blue (MB), malachite green (MG), Congo red (CR), and crystal violet (CV) dye aqueous solutions were used to evaluate the photocatalytic performance of the synthesized Ag-modified TiO2 nanofibers (NFs) under direct sunlight irradiation. The effects of catalyst size on the efficient breakdown of MB dye were also investigated. The optimum catalyst concentration was found to be at 0.02 mg/mL. At 120 min of direct sunlight, the highest photosynthetic degradation efficiency (DE percentage) of 94% was achieved for MB dye. Ag-TiO2 nanofibers (NFs) have been demonstrated to have exceptional antibacterial activity against Gram-positive bacteria such as Staphylococcus aureus and Gram-negative bacteria E-Coli. Because of these great qualities, it seems likely that the Ag-TiO2 nanofibers (NFs) made could be a great photocatalyst for getting dye pollutants out of wastewater.
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Nanopartículas Metálicas , Nanofibras , Nanofibras/química , Nanopartículas Metálicas/química , Prata/química , Titânio/química , Antibacterianos/químicaRESUMO
Sustainable fabrication of flexible hybrid supercapacitor electrodes is extensively investigated during the current era to solve global energy problems. Herein, we used a cost-effective and efficient electrophoretic deposition (EPD) approach to fabricate a hybrid supercapacitor electrode. ZnO/CuO and ZnO/CuO/rGO heterostructure were prepared by sol-gel synthesis route and were electrophoretically deposited on indium tin oxide (ITO) substrate as a thin uniform layer using 1 V for 20 min at 50 mV/s. ZnO/CuO and ZnO/CuO/rGO heterostructure coated ITOs were then employed as the working electrode in a three-electrode setup for supercapacitor measurements. The fabricated electrodes have been investigated by Galvanostatic charge-discharge (GCD), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) to study their charge storage properties. ZnO/CuO revealed a specific capacitance of 1945 F g-1 at 2 mV/s and 999 F g-1 at 5 A g-1. However, an increased specific capacitance of 2305 F g-1 was measured for ZnO/CuO/rGO heterostructure at 2 mV/s and 1235 F g-1 at 5 A g-1. The lower internal resistance was observed for ZnO/CuO/rGO heterostructure, indicating good conductivity of the electrode material. Thus, the overall results of the current study suggest that EPD-assisted ZnO/CuO/rGO heterostructure hybrid electrode possess a substantial potential for energy storage as a supercapacitor.
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Óxido de Zinco , Cobre , EletrodosRESUMO
Dye-Sensitized Solar Cells (DSSCs) have attracted great attention due to environmentally friendly low-cost processing, excellent working ability in diffuse light, and potential to meet the power demands of future buildings due the true class of building integrated photovoltaics (BIPV). Nevertheless, DSSCs have relatively low photoconversion efficiency (PCE) due to multiple issues. Several strategies have been employed to enhance its PCE. For instance, bi-layered structure of photoelectrode i.e., mesoporous TiO2 transparent layer with top scattering layer was introduced which scatter light inside on large angles improves the harvesting ability of photoelectrode thus enhanced PCE. However, scattering layer is composed of aggregated small particles which offer sluggish electron transport due to multiple grain boundaries, consequently, unwanted recombination reaction which leads to poor PCE. This issue has been addressed for transparent layer immensely but ignored for scattering layer. Mostly for scattering layer in previous studies novel structures have been proposed to enhance scattering properties and dye adsorption only. Therefore, in this study for the first time presenting dual functional graphene/TiO2 scattering layer in which solvent exfoliated graphene is incorporated in TiO2 submicron spheres which enhanced electron transport properties, while submicron spheres scatter light effectively. Scattering and electron transport characteristics of DSSCs are thoroughly investigated with the function of graphene loading. Electrochemical impedance spectroscopy (EIS) has revealed that diffusion coefficient length and coefficient and conductivity attained maximum value at 0.01 wt%. while other important parameters such as electron lifetime and electron density in conduction band have been improved till 0.020 wt% graphene loading. However, results indicated that with 0.01 w% graphene 33% higher PCE was achieved than without scattering layer and 13% higher than scattering layer without graphene. The depraving in PCE at >0.01 wt% graphene despite of excellent electron transport improvement is attributed to the loss of diffuse reflectance and higher optical absorption by graphene.
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Grafite , Adsorção , Corantes , Espectroscopia DielétricaRESUMO
Considering that H2S is a hazardous gas that poses a significant risk to people's lives, research into H2S gas sensors has garnered a lot of interest. This work reports a CuO/ZnO multifaceted nanostructures(NS) created by heat treating Cu2+/ZIF-8 impregnation precursors, and their microstructure and gas sensing characteristics were examined using various characterization techniques (XRD, XPS, SEM, TEM, and BET). The as-prepared hollow CuO/ZnO multifunctional nanostructures had a high gas response value (425@50 ppm H2S gas), quick response and recovery times (57/191s @20 ppm), a low limit of detection (1.6@500 ppb H2S), good humidity resistance and highly selective towards H2S gas. The hollow CuO/ZnO multifaceted nanostructures possessed enhanced gas sensing capabilities which may be related to their porous hollow nanostructures, the manufactured p-CuO/n-ZnO heterojunctions, and the spillover effect between CuO and H2S.
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Nanoestruturas , Óxido de Zinco , Humanos , Comércio , CobreRESUMO
The inherent toxicity, mutagenicity and carcinogenicity of dyes that are discharged into aquatic ecosystems, harming the health of humans and animals. ZIF-8 based composites are regarded as good adsorbents for the breakdown of dyes in order to remove or degrade them. In the course of this research, metal-organic framework materials known as ZIF-8 and its two stable composites, ZIF-8/BiCoO3 (MZBC) and ZIF-8/BiYO3 (MZBY), were produced via a hydrothermal process and solvothermal process, respectively, for the dangerous Congo red (CR) dye removal from the solution in water using adsorption method. According to the findings, the most significant amount of CR dye that could be adsorbed is onto MZBC, followed by MZBY and ZIF-8. The pseudo-second-order kinetic model was used effectively to match the data for adsorption behavior and was confirmed using the Langmuir isotherm equation. There is a possibility that the pH and amount of adsorbent might influence the adsorption behavior of the adsorbents. According to the experiment results, the technique featured an endothermic adsorption reaction that spontaneously occurred. The higher adsorption capability of MZBC is because of the large surface area. This results in strong interactions between the functional groups on the surface of MZBC and CR dye molecules. In addition to the electrostatic connection between functional group Zn-O-H on the surface of ZIF-8 in MZBC and the -NH2 or SO3 functional group areas in CR molecules, it also includes the strong π-π interaction of biphenyl rings.
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Poluentes Químicos da Água , Purificação da Água , Animais , Humanos , Ecossistema , Poluentes Químicos da Água/análise , Corantes , Purificação da Água/métodos , Adsorção , Cinética , Concentração de Íons de HidrogênioRESUMO
The detection of hydrogen sulfide (H2S) is critical because of its potential harm and widespread presence in the oil and gas sectors. The zeolitic imidazolate framework-8 (ZIF-8) derived ZnO nanostructures manufactured as gas sensors have exceptional sensitivity and selectivity for H2S gas. In/Zn-ZIF-8 template material was synthesized by a simple one-step co-precipitation method followed by thermal annealing in air. The heat treatment resulted in In2O3/ZnO nanostructures with mixed heterostructures. The crystal structure (XRD), morphology (SEM/TEM), chemical state (XPS), surface area (BET), etc were investigated to ascertain the nature of the as-prepared material. SEM imagery revealed that the as-prepared In2O3/ZnO sensitive material had a microstructure of porous hollow nanocages with an average particle size of about 200 nm, which is beneficial to the diffusion and adsorption of gas molecules. The gas sensing performance test results of the In2O3/ZnO hollow nanocages show that their response to H2S gas is significantly improved 67.5 @50 ppm H2S (about 11 times that of pure ZnO nanocages) at an optimal temperature of 200 °C, better selectivity, lower theoretical detection limit and good linearity between gas concentration and response values. The enhanced gas sensing feat to H2S gas is mainly attributed to the formation of n-n heterojunction and the wide surface area of the newly formed In2O3/ZnO porous hollow nanocages.
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Estruturas Metalorgânicas , Zeolitas , Óxido de Zinco , Adsorção , Comércio , DifusãoRESUMO
Photocatalysis is considered a useful technique employed for the dye degradation through solar light, visible or UV light irradiation. In this study, TiO2, g-C3N4, and TiO2-g-C3N4 nanocomposites were successfully synthesized and studied for their ability to degrade Rhodamine B (RhB) and Reactive Orange 16 (RO-16), when exposed to visible light. The analytical techniques including XRD, TEM, SEM, DRS, BET, XPS, and fluorescence spectroscopy were used to explore the characteristics of all the prepared semiconductors. The photocatalytic performance of synthesized materials has been tested against both the selected dyes, and various experimental parameters were studied. The experimental results demonstrate that, in comparison to other fabricated composites, the TiO2-g-C3N4 composite with the optimal weight ratio of g-C3N4 (15 wt%) to TiO2 has shown outstanding degrading efficiency against RhB (89.62%) and RO-16 (97.20%). The degradation experiments were carried out at optimal conditions such as a catalyst load of 0.07 g, a dye concentration of 50 ppm, and a temperature of 50 â at neutral pH in 90 min. In comparison to pure TiO2 and g-C3N4, the TiO2-g-C3N4, a semiconductor, has shown higher degradation efficiency due to its large surface area and decreased electron-hole recombination. The scavenger study gave an idea about the primary active species (-OH radicals), responsible for dye degradation. The reusability of TiO2-g-C3N4 was also examined in order to assess the composite sustainability.
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Corantes , Luz , Raios Ultravioleta , Titânio/químicaRESUMO
An ecofriendly and cost effective green method has been used for the synthesis of recyclable, high functional nanoparticles. Bimetallic nanoparticles (BmNPs), Cu-Ag, have been synthesized using beetroot extract as reducing and capping agent. Formation of BmNPs was initially confirmed by UV-visible analysis, having distinct peaks of Ag at 429 nm and Cu at 628 nm. FTIR analysis also confirmed the association of bioactive phytochemicals with Cu-Ag nanoparticles. Crystallinity and morphology of BmNPs was determined through X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS) and energy dispersion X-ray spectroscopy (EDAX). The size of spherical shape Cu-Ag BmNPs was found to be 75.58 nm and EDAX studies confirmed the percent elemental composition of Cu and Ag in synthesized nanocatalyst. Results of different analysis provided supported evidences regarding the formation of BmNPs. Catalytic potential of BmNPs was tested for the degradation of rhodamine B (Rh-B), methylene blue (MB) and methyl orange (MO) dyes. Cu-Ag BmNPs exhibited outstanding catalytic activity for the degradation of selected organic dyes and percent degradation was recorded more than 90% for each dye. In addition, antiradical property of BmNPs was tested employing DPPHâ and ABTSâ+ assays and it was found to be promising. Synthesized BmNPs also exhibited strong antimicrobial activity against Salmonella typhimurium and Bacillus subtilis. Recyclability of nanoparticles was also evaluated and recovery from dye degradation reaction mixture was successfully achieved. The recovered nanoparticles exhibited same catalytic potential for the degradation of Rh-B. The objective of the current study was to synthesize BmNPs Cu-Ag employing a cost effective green method having promising catalytic, antiradical and antimicrobial potential. Further, BmNPs were reused after recovery from catalytic reactions, proving that BmNPs can be recycled having the same efficiency as that of a freshly prepared Cu-Ag BmNPs.