Corrosion is a harmful processes which by definition is a chemical or electrochemical reaction between a substance (usually a metal) and the environment which leads to a change in the properties of ...the substance and has destructive effects. In this study, new composites consisting of Al/WS2/ZnTerp-2TH with 5 and 10 wt.% ZnTerp-2TH were prepared and the results were fully compared. Al/WS2 played the role of matrix and ZnTerp-2TH played the role of reinforcement. In other words, as a novelty to prevent the corrosion of Al/WS2, ZnTerp-2TH is designed and synthesized and showed good results when the corrosion ratio was reduced by the existence of ZnTerp-2TH. Furthermore, the NMR and mass analysis of ZnTerp-2TH were carried out, and the thermal properties, X-ray diffraction, Fourier-transform infrared (FTIR) spectroscopy, morphology, energy-dispersive X-ray spectroscopy (EDX) analysis and corrosion behavior of the composites were also discussed in detail. The crystal size values of composites were calculated by the modified Scherrer method 34, 26 and 27 nm for Al/WS2, Al/WS2/5 wt.% ZnTerp-2TH and Al/WS2/10 wt.% ZnTerp-2TH, respectively. The microstructural examination of the specimens showed that the reinforcing phase (ZnTerp-2TH) has a favorable distribution on the surface of Al/WS2 when it covers the cracks and holes. In addition, the corrosion investigation results showed that the addition of ZnTerp-2TH to Al/WS2 can improve the corrosion resistance when the Ecorr and Icorr values of Al/WS2/10 wt.% ZnTerp-2TH were recorded in tandem −724 mV/decade and 5 uA cm−2.
Photovoltaic systems, such as dye-sensitized solar cells (DSSCs), are one of the useful tools for generating renewable and green energy. To develop this technology, obstacles such as cost and the use ...of expensive compounds must be overcome. Here, we employed a new MoS2/graphene hybrid or composite instead of platinum in the DSSCs. Furthermore, the correctness of the preparation of the MoS2/graphene hybrid or composite was evaluated by field emission scanning electron microscope (FESEM), and the results showed that the desired compound was synthesized correctly. Inexpensive organic dyes were used to prepare the DSSCs, and their chemical structure was investigated by density functional theory (DFT) and cyclic voltammetry (CV). Finally, the DSSCs were fabricated using MoS2/graphene composite or hybrid, and to compare the results, the DSSCs were also prepared using platinum. Under the same conditions, the DSSCs with MoS2/graphene composite illustrated better efficiency than MoS2/graphene hybrid or/and graphene.
Nanomaterials are the sixth most emerging contaminants that are entering into aquatic habitat posing a risk to the inhabiting organisms. Nanoparticles of copper ferrite have been extensively used in ...biomedical applications. However, very limited studies are available on the cytotoxicity evaluation of copper ferrite nanoparticles (CuFe2O4NPs) on different cell lines. The current work investigates on the cytotoxicity, oxidative stress and morphological variations triggered by CuFe2O4NPs in Channel catfish ovary (CCO) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT), neutral red uptake (NRU), lipid peroxidation (LPO), catalase (CAT), reduced glutathione (GSH), glutathione sulfotransferase (GST) and glutathione peroxidase (GPX) assays after 24 h of treatment. Dose dependent decline in cell survival was noticed in MTT and NRU assays. A significant increase in LPO, GST and GPX was observed in CCO cells exposed to CuFe2O4NPs after 24 h of treatment. However, the CAT and GSH levels in CCO cells exposed to CuFe2O4NPs decreased significantly after 24 h. The CCO cells exposed to 10 μg/mL concentration of CuFe2O4NPs for 24 h showed remarkable changes in their morphology. Further, the study also describes the detailed mechanism of toxicity of CuFe2O4NPs in other model cell lines to probe the risk of inhabiting organisms.
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•The cytotoxicity of CuFe2O4NPs was evaluated using CCO cells.•MTT and NRU assays revealed CuFe2O4NPs are highly toxic to CCO cells.•CuFe2O4NPs induced morphological changes in CCO cells cell after treatment.
This study reports the synthesis and photophysical properties of a star‐shaped, novel, fluoranthene–tetraphenylethene (TFPE) conjugated luminogen, which exhibits aggregation‐induced blue‐shifted ...emission (AIBSE). The bulky fluoranthene units at the periphery prevent intramolecular rotation (IMR) of phenyl rings and induces a blueshift with enhanced emission. The AIBSE phenomenon was investigated by solvatochromic and temperature‐dependent emission studies. Nanoaggregates of TFPE, formed by varying the water/THF ratio, were investigated by SEM and TEM and correlated with optical properties. The TFPE conjugate was found to be a promising fluorescent probe towards the detection of nitroaromatic compounds (NACs), especially for 2,4,6‐trinitrophenol (PA) with high sensitivity and a high Stern–Volmer quenching constant. The study reveals that nanoaggregates of TFPE formed at 30 and 70 % water in THF showed unprecedented sensitivity with detection limits of 0.8 and 0.5 ppb, respectively. The nanoaggregates formed at water fractions of 30 and 70 % exhibit high Stern–Volmer constants (Ksv=79 998 and 51 120 m−1, respectively) towards PA. Fluorescence quenching is ascribed to photoinduced electron transfer between TFPE and NACs with a static quenching mechanism. Test strips coated with TFPE luminogen demonstrate fast and ultra‐low‐level detection of PA for real‐time field analysis.
Detecting explosives: A tetraphenylene‐based luminogen (TFPE) exhibits aggregation‐induced blue‐shifted emission (AIBSE). Nanoaggregates of this luminogen have good selectivity and high sensitivity towards 2,4,6‐trinitrophenol (PA) over other nitroaromatic compounds (NACs, see figure).
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•Straightforward synthesis of anthrapyrazolone-based novel fluorescent polymeric hydrogel (P(OEGMA-co-DIMA)), for the detection of TC in aqueous medium.•The quenching investigations ...of P(OEGMA-co-DIMA) shows the potential quenching of TC with highest Ksv value of 9.99 x 103 M−1 and a LOD of 1.3 nM.•Therefore, P(OEGMA-co-DIMA) can be used for quick detection and identification of TC contamination in different water and milk samples without any interference.
Tetracycline (TC) antibiotics are essential for treating bacterial infections; however, overuse and improper disposal place the environment in danger and promote the growth of drug-resistant microorganisms. Monitoring their impact on living organisms is vital. Polymeric-based hydrogels offer promise in antibiotic detection due to their versatility and biocompatibility, despite their uncommon use for this purpose. In this study, we have synthesized a fluorescent polymeric hydrogel, P(OEGMA-co-DIMA) utilizing oligo(ethylene glycol)methyl ether methacrylates (OEGMA) and laboratory-synthesized fluorescent anthrapyrazolone containing monomer, 2-(benzo1,2,3-cd:4,5,6-c’dbis(indazole)-2(7H)-yl)ethyl methacrylate (DIMA) for the fluorometric detection of TC in the aqueous medium. The P(OEGMA-co-DIMA) hydrogel exhibited exceptional affinity towards TC while exhibiting high selectivity. The chemosensing behavior of the hydrogel was also compared with the DIMA monomer. Upon adding TC, emission analysis revealed a notable quenching in the emission intensity of the P(OEGMA-co-DIMA) hydrogel as well as the DIMA monomer. The Stern Volmer rate constants (Ksv) of the hydrogel (Ksv = 9.99 x 103 M−1) in water and DIMA (Ksv = 25.63 x 103 M−1) in acetonitrile showed a higher quenching rate constant with a limit of detections (LODs) of 1.3 nM and 0.11 nM. Turn-off fluorescence behavior occurs via a static quenching mechanism through a photoinduced electron transfer process and intermolecular hydrogen bonding. To validate the selectivity, the interference analyses in an aqueous medium with different antibiotics are provided. To rationalize the real-time applicability of the hydrogel, studies were extended to water samples obtained from deionized water, tap water, lake water, and also in milk samples. The recovery rate and LOD for real samples ranged from 83.8% to 111% and 0.83 to 3.6 nM, respectively.
•Role of intermolecular hydrogen bonding interactions of freebase porphyrins with 2,4,6-trinitrophenol is analyzed.•Formation of 1:2 molecular adducts analyzed with SXRD, NMR and DFT.
Three different ...types of meso‑substituted freebase porphyrins (H2TTP, H2TMP and H2DDMP) with varied number and nature of electron donating groups (-CH3 and –OCH3) were synthesized. The molecular interactions of the porphyrins with different phenol derivative were explored using single crystal X-ray, NMR and their affinity by varied spectroscopic techniques. All three freebase porphyrins undergo strong intermolecular interactions with 2,4,6-trinitrophenol (TNP) and crystallized in a triclinic crystal system with iso-structural behaviour. The crystal lattices are stabilized through intermolecular hydrogen bonding interactions (N–H∙∙∙O and C–H∙∙∙O) and electrostatic interactions. Increases in the non-planarity of freebase porphyrins enhance the reactivity which results in the formation of picrate anions with 1:2 adduct formation by proton transfer process. The role of weak intermolecular interactions was analysed and quantified through Hirshfeld surface and finger print analysis. DFT studies revealed that the electron-donating effect of the methoxy group plays a major role in decreasing HOMO-LUMO gap and in-plane co-operation through the decrease in the dihedral angles. The electron density at bond critical points follows the order H2TTP.2TNP>H2TMP.2TNP>H2DDMP.2TNP. Absorption and emission studies showed that dramatic changes in the Soret and Q-band pattern and the binding constants were altered with different phenols of varied pKa. The stabilization of molecular adducts were analyzed in correlation with 1H- NMR study to reveal the involvement of the hydrogen bonding.
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•N-doped porous carbons (PSC-3-X) were synthesized from hypercrosslinked polystyrene foam waste.•High specific surface area and heteroatoms were introduced into PSC-3-X.•The materials ...exhibit hierarchical porous structures with well-defined microporosity.•The optimized material (PSC-3-700) exhibits a specific capacitance of 327 F g−1 and excellent cycle stability.•PSC-3-700 show high electrosorption capacity of 34.8 mg g−1.
We have utilized cheap and readily available expanded polystyrene (EPS) foam waste as a raw material for the synthesis of a hypercrosslinked polymer. Using this polymeric scaffold, we have synthesized a series of nitrogen-doped porous carbons (PSC-3-X) via KOH activation at different temperatures. The optimized carbon material (PSC-3-700) exhibits a specific surface area of 810 m2 g−1 and optimum porosity suitable for capacitive applications such as supercapacitors and capacitive deionization. Moreover, the high nitrogen (5.23%) and oxygen (8.93%) contents present in the material enhances the electrochemical performance. PSC-3-700 exhibits the highest specific capacitance of 327 F g−1 at 1.0 A g−1 in 1 M H2SO4 aqueous electrolyte and 100% capacitance retention even after 10,000 charge–discharge cycles. It also displays a high electrosorption capacity of 34.8 mg g−1 for 500 mg L−1 NaCl solution at an applied voltage of 1.6 V in capacitive deionization application. The charge storage mechanism and electrosorption kinetics of the material have been investigated in detail.
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•Simple functionality and small size are the advantages of the phenothiazine to develop a low cost material.•Being simple secondary amine with an amine content of 7.5 % the molecule ...exhibits a CO2 capture capacity of 17 mg/g.•A linear response is obtained for CO2 concentration varied between 0.04 to 15 %, thus, this material can be used for direct CO2 capture from air.
Globally, CO2 levels are rising and thus, dedicated efforts are driven towards CO2 capture and storage. In this work, we have demonstrated for the first time CO2 adsorption and storage by phenothiazine (Pheno) molecule. The amine functionalities of Pheno are exploited for the chemisorption of CO2. A maximum of 0.4 mmol/g of CO2 is adsorbed which equates to 17.6 mg CO2 captured/g of Pheno molecule. This value may seem less but the small size, simplistic functionalities, and cheap cost make this study relevant for CO2 mitigation. The CO2 stored on the Pheno molecule is chemisorbed to form strong carbamide (amide linkage) and thus, difficult to desorb even at a temperature of 150 °C. This shows that CO2 is stored strongly (via chemical bond formation) and safely thus, could reduce the accidents resulting from accidental leakage/desorption of CO2 which could be fatal. Pheno based sorbent shows linear response over various concentrations ranging from atmospheric concentration of CO2, 400 ppm to 15% concentrations of CO2 at ambient conditions. The adsorption efficacy of Pheno exponentially decreases with an increase in temperature above room temperature. However, the adsorption efficiency increases with an increase in relative humidity as non-condensable water molecules further provide an additional site for CO2 dissolution and bicarbonate formation which increases CO2 uptake.
A novel fluorometric chemical sensor (PY-2TH) based on 2-thiohydantoin (2TH) in conjugation with pyrene (PY) was designed by facile one-pot Knoevenagel condensation reaction and explored for the ...sensitive and selective detection of Hg2+ ion in solution and solid state methods. Different analytical techniques like NMR and LC-MS concomitantly confirmed the structure of PY-2TH. Absorption and emission studies demonstrate positive solvatochromic effects indicating intramolecular charge transfer in polar solvents. PY-2TH exhibits unprecedented selectivity for detecting Hg2+ ions in tetrahydrofuran (THF) through turn-OFF fluorescence with 90% decrease in the emission intensity with a limit of detection (LOD) of ∼4.4 ppb. The mechanistic investigation through NMR and optical studies confirm the formation of a 2:1 complex between PY-2TH and Hg2+. Thin films of PY-2TH exhibits the J-aggregate formation in the solid state leading to a shift in the emission towards the near-infrared region. Further, we have demonstrated the applicability of PY-2TH for detection of Hg2+ ions and fluorescence imaging in live Zebrafish larvae and the toxicological effects are explored. Cytotoxic evaluation on Zebrafish larval cells revealed that PY-2TH is found to be non-toxic. Detailed analysis demonstrate the potential of PY-2TH for ultra-sensitive Hg2+ ion detection and removal in aqueous environments, highlighting its applicability for identification of metal contamination in live organisms and environmental toxicity.
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•Novel fluorescent PY-2TH designed using 2-thiohydantoin and pyrene through one-pot Knoevenagel condensation reaction.•Solvatochromic effects observed in absorption and emission studies concur intramolecular charge transfer in polar solvents.•PY-2TH demonstrates remarkable selectivity for detection of Hg2+ ions, exhibiting turn-OFF behaviour with LOD of 22 nM.•Assess the metal contamination in live organisms and environmental toxicity.
Highly functionalized quinazolin‐4(3H)‐ones were synthesized from reactions of N‐aryl‐2‐aminobenzamides with trialkylamines under photocatalytic conditions by using eosin Y (EY) as a catalyst. The ...reaction proceeds under mild conditions in aqueous acetonitrile and has a broad substrate scope. Mechanistic studies disclosed the electron‐donor nature of the intermediate 2,3‐dihydroquinazolin‐4(1H)‐one (3’) in the photocatalytic cycle to afford the 2,3‐disubstituted‐quinazolin‐4(3H)‐ones (3). This methodology has been extended to synthesize benzo 4,5 imidazole1,2‐c quinazolines and 3 aa on a large scale. Furthermore, the synthesis of potent central nervous system depressant (CNS) drug molecules such as methaqualone (3 la) and mecloqualone (3 pa) was also achieved successfully.
A metal‐free, visible‐light photocatalytic approach for the construction of 2‐alkyl substituted quinazolin‐4(3H)‐ones and benzo4,5imidazo1,2‐cquinazolines using trialkylamines as carbon synthons has been developed. Some of the notable features of this methodology include the synthesis of potent central nervous system depressants (CNS) drug molecules methaqualone (3 la), mecloqualone (3 pa) and gram‐scale synthesis.
