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•SnO2-nanowire have been synthesized using PFG400 as a structural directing agent at room temperature.•The SnO2-nanowire/GCE sensor was first used to detect hydrogen ...peroxide.•Theoretical calculations indicate that the adsorption capacity of SnO2 (110) crystal surface for H2O2 is superior to that of SnO2 (101) crystal surface.•This sensor has good practicality for detecting H2O2 in orange juice and tap water.
In this paper, SnO2-nanowire was synthesized and constructed as non enzymatic sensor to detect hydrogen peroxide (H2O2). In 0.1 M PBS, the prepared SnO2-nanowire/GCE amperometric sensor exhibits a well performance against H2O2, with the linear detection range of 1.4 μM ∼ 6.66 mM and detection limit of 0.34 μ M. This superior electrochemical sensing performance is mainly due to the mesoporous structure, large specific surface area, and high conductivity of the SnO2 nanowire. Theoretical calculations indicate that the adsorption capacity of SnO2 (110) crystal surface for H2O2 is superior to that of SnO2 (101) crystal surface. In addition, the sensor can detect hydrogen peroxide in tap water and orange juice, showing its potential applications.
Two fused N‐heterocyclic scaffolds were selectively functionalized giving access to novel pharmaceutical targets that offer a better life to the whole world. More information can be found in the ...Research Article by P. Knochel and co‐workers (DOI: 10.1002/chem.202200733).
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•Adsorption behaviors of ibuprofen and naproxen by UiO-66 and UiO-66-NH2.•Adsorption mechanisms of ibuprofen and naproxen were revealed by DFT calculation.•π-π EDA, H-bonding, LAB ...complexing, and anion-π interaction were involved.•The binding energies followed the order of π-π > hydrogen bonding > LAB > anion-π.
Ibuprofen (IBP) and naproxen (NAP), two typical anti-inflammatory drugs, were frequently detected in natural waters. Therefore, their adsorption to various materials has drawn great interests. However, the adsorption mechanisms of IBP and NAP at a molecular level were not well-known. This study investigated the adsorption of IBP and NAP by two types of metal organic frameworks (MOFs), UiO-66 and UiO-66-NH2, and the adsorption mechanisms were revealed at macro and micro molecule levels based on experiments and density functional theory (DFT) calculations. Greater adsorption of IBP onto MOFs was observed compared with NAP, which is incurred by its higher binding energies with adsorbents than NAP as revealed by DFT calculations. Four mechanisms, including π-π EDA interaction, Lewis acid/base complexing (LAB), hydrogen bonding, and anion-π interaction, were simultaneously involved in the adsorption of IBP/NAP by MOFs. The binding energies followed the order of π-π > hydrogen bonding > LAB > anion-π. The decreasing adsorption of IBP and NAP with rising pH was induced by the facilitated aggregation of MOFs at pH < pHpzc and the electrostatic repulsion between IBP/NAP and MOFs at pH > pHpzc. Direct competition for adsorption sites accounted for the competitive adsorption between IBP and NAP, and the extra type of binding site (amino group) and less amount of adsorption sites induced the less competition between IBP and NAP onto UiO-66-NH2 compared with UiO-66. This study, at a molecular level, provides adsorption mechanisms of acidic pharmaceuticals with MOFs.
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•A universal strategy was adopted to produce defective Zr-MOFs like NH2-UiO-66.•The defective SS-NH2-UiO-66-X originated from the missing linker and Zr-O clusters.•SS-NH2-UiO-66-X ...displayed effective and selective adsorption toward Pb(II).
Within this work, a green and facile approach was proposed to modulate NH2-UiO-66 for purpose of obtaining SS-NH2-UiO-66-X (“X” implied the dosage of used SS) using seignette salt (SS). The generation of abundant vacancies with the formation of hierarchical pores boosted their sorption performance for lead (Pb(II)), which strengthened the mass transfer of Pb(II) in SS-NH2-UiO-66-X interior. Particularly, the optimal SS-NH2-UiO-66-5 exhibited good adsorption capacity toward Pb(II) (186.14 mg g−1) and fast diffusion rate (32.1 mg g−1·min0.5) at 25 °C and initial pH = 5.46, which were about 34.2 and 66.9 times higher than those of the pristine NH2-UiO-66, respectively. SS-NH2-UiO-66-5 could selectively capture the Pb(II) from simulated wastewater containing different co-existing ions. The mechanism was proposed that the defect sites played a significant role in boosting the Pb(II) capture performance, which was further affirmed by X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectra (XPS). The density functional theory calculations (DFT calculations) illustrated that the hierarchical pores and rich vacancies enhanced the Pb(II) mobility toward the adsorption active sites and reduced the adsorption energy between SS-NH2-UiO-66-X and Pb(II). This defect engineering approach could be introduced to modulate other Zr-MOFs like MOF-801, UiO-66 and MOF-808, which presented a general strategy to fabricate defective Zr-MOFs for the boosted adsorption performance toward pollutants removal from wastewater.
Herein we report the use of an air- and moisture-stable dinuclear Pd(I) complex as an efficient catalyst for the formation of C(sp2)-SeR bonds. The privileged reactivity of the Pd(I) dimer allows the ...direct use of selenolates as nucleophiles in the cross-coupling. While previous methodologies suffer from catalyst poisoning through the formation of Pd-ate complexes, the mechanistically distinct dinuclear Pd(I)-catalyst circumvents this challenge. A wide variety of aryl bromides and iodides were efficiently coupled under relatively mild reaction conditions with broad functional group tolerance. Mechanistic and computational data are presented in support of direct Pd(I) reactivity.
Designing new metal-based molecular antibiotics is an efficient approach to overcome the growing threat of antimicrobial resistance. In this paper, novel Cr(III), Fe(III) and Cu(II) complexes ...comprising substituted aryl imidazole ligand (MSEB), namely (2-(1-(2-hydroxyethyl)-4,5-diphenyl-1H-imidazole-2-yl)(4-bromophenol)) have been synthesized and characterized using infra-red (IR), ultraviolet-visible (UV-Vis) and 1H, 13C NMR spectroscopic techniques, together with elemental (CHN) and thermogravimetric analyses, molar conductance, and magnetic susceptibility measurements. The combined results along with the DFT calculations revealed a 1:1 (M: L) stoichiometric ratio and the complexes adopted distorted-octahedral geometries to afford Cr(MSEB)Cl2(H2O)2, Fe(MSEB)(NO3)2(H2O)2 and Cu(MSEB)Cl(H2O)3 respectively. Biological studies showed that all complexes exhibited powerful antimicrobial activity against various strains of bacteria and fungi, S. aureus (+ve), E. coli (-ve) and P. aeruginosa (-ve) bacteria and T. Rubrum, C. albicans, and A. flavus fungi. Moreover, the three metal-complexes showed high in vitro cytotoxicity against Colon (HCT-116), Breast (MCF-7), and hepatic cellular (HepG-2) carcinoma cell lines, with MSEBCu complex being the most cytotoxic one. Finally the binding interactions of the complexes with CT-DNA were explored using UV-Vis spectroscopy, viscosity and gel electrophoreses measurements.
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•Some new aryl imidazole complexes were synthesized.•The investigated compounds were characterized via various physicochemical tools.•Antimicrobial activities of the prepared compounds were screened.•Interaction of the prepared complexes with CT-DNA was investigated.•Anticancer activities of the prepared ligand and its complexes were checked.
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•The composite photocatalyst with multi charge transfer channels was constructed.•The multi charge transfer modes enhanced charge mobility and separation of e--h+.•The composite ...exhibited significantly enhanced activity for SMZ degradation.•Condensed dual descriptors based DFT helped to precisely predict the reactive sites.
Rational design of highly efficient multi-heterojunction photocatalyst with separated charge transfer channels still remains a challenge. Herein, a novel La2Ti2O7/g-C3N4/AgI photocatalyst is constructed via a facile electrostatic self-assembly plus selective deposition–precipitation method. The results demonstrate that the spatially isolated La2Ti2O7 and AgI are both decorated tightly on g-C3N4 nanosheets and form separated heterojunctions, which provide much more separated charge transfer channels and surface reaction sites. Therefore, the samples exhibit remarkably boosted photodegradation performance for sulfamethoxazole (SMZ). DFT results indicate that the atoms with the most positive and negative value of condensed dual descriptors (CDD) are the mostly vulnerable to reactive species. Aromatic amine oxidation, the cleavage of sulfonamide bond and hydroxylation of aromatic rings are mainly SMZ degradation pathways. This study provides a new insight for the guideline of rational design/development of new multicomponent photocatalysts for potential application on treatment of emerging pollutants in waters.
The synergistic effect between photocatalytic and peroxymonosulfate (PMS) activation has been widely applied in the field of sewage treatment. In this work, we synthesized a ...two-dimensional/two-dimensional (2D/2D) CoAl-LDH/BiOBr Z-scheme photocatalyst via a simple method. Then, multiple detection results demonstrated that CoAl-LDH was successfully anchored onto BiOBr, as well as formed an intimate interaction. Moreover, the photocatalytic degradation performance of the catalysts/PMS/vis system had been explored under several conditions (e.g., different catalyst doses, PMS doses, anions and pollutants). The 8 wt% CoAl-LDH/BiOBr composite exhibited the highest degradation efficiency (96%) of ciprofloxacin (CIP). In addition, radicals quenching experiments and electron paramagnetic resonance (EPR) indicated that •O2ˉ and 1O2 were the primary radicals for CIP degradation. The photoelectrochemical measurement and photoluminescence (PL) confirmed that 8 wt% CoAl-LDH/BiOBr exhibited the highest separation and transfer rate of charge carriers. The liquid chromatography-mass spectrometer (LC-MS) analysis revealed that oxidation of the piperazine ring and defluorination were the main CIP degradation pathways. Density functional theory (DFT) calculation, including the laplacian bond order (LBO) and Fukui index, which was consistent with the results of LC-MS. This study explained the superiority of the synergistic effect between photocatalysis and PMS activation on the degradation of pollutants.
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•A novel 2D/2D CoAl-LDH/BiOBr Z-scheme photocatalyst is prepared.•The synergistic effect between photocatalytic and PMS activation.•The reactive sites of ciprofloxacin are firstly revealed by laplacian bond order and Fukui index according to DFT calculation.•The possible degradation pathways of ciprofloxacin and the toxicity of degraded intermediates are suggested.••O2ˉ and 1O2 are the main radicals for ciprofloxacin degradation.
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•A facile defect-engineering approach was used to synthesis UiO-67.•The high toluene uptake is obtained due to missing and compensating linker defects.•Water molecule exhibited ...promoting effect on the toluene adsorption of UiO-67.•Synergic effects between π-π, OH-CH3 and OH-π obviously enforced toluene adsorption.
A facile defect-engineering approach enabled by introducing monocarboxylic acid modulators (acetic acid, formic acid and benzoic acid) was conducted in this paper. The greatest toluene uptake (480 mg g−1) was obtained on defective UiO-67 synthesized with benzoic acid due to highest missing linker defects and higher compensating linker defects. It is worth mentioning that water molecule exhibited creative promoting effect on the adsorption behavior of defective UiO-67. The original structure of defective UiO-67 was inevitably destroyed under water-containing environment due to the coordination between water molecule and metal cluster. 1H NMR analysis demonstrated that slight loss of BPDC linkers and benzoate linkers due to occupied binding sites, more extra adsorption sites were generated in this process. Furthermore, adsorption mechanisms were studied via density functional theory (DFT) calculations. The synergic effects between π-π, OH-CH3 and OH-π hydrogen bonding strength obviously enforced toluene adsorption, and OH-π exhibited strongest interaction. Moreover, under the circumstance of structural changes due to water molecules, abundant μ3-OH groups were exposed and hydrogen bond interaction was strengthened, which greatly promoted toluene adsorption. Finally, experimental results as well as computational studies forecasted the potentials of defect-tunable MOFs as promising materials in gas adsorption.
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•K/halogen atoms co-doping modulates the band structure and electron density.•Oxygen adsorption and activation sites are constructed in CN-KX catalysts.•Abundant O2− generate over ...CN-KI catalyst due to O2adsorption andelectron transfer.
Graphite carbon nitride (g-C3N4) is a promising photocatalyst,but its inadequate reactive sites, weak visible light responsiveness, and sluggish separation of photogenerated carriers hamperthe improvement of photodegradation efficiency. In this work, potassium (K) and halogen atoms co-modified g-C3N4 photocatalysts (CN-KX, X = F, Cl, Br, I) were constructed to adjust the electrical and band structure for enhanced generation of reactive oxygen species. Through an integration of theoretical calculation and experimental exploration, the doping sites of halogen atoms as well as the evolution of crystal, band, and electronic structures were investigated. The results show that a covalent bond is formed between the F atom and the C atom, substitution of the N atom occurs with a Cl atom, and doping of Br, I, or K atoms takes place at the interstitial site. CN-KX photocatalysts exhibits lower band gap, faster photogenerated electron migration, and enhanced photocatalytic activity. Specifically, the CN-KI photocatalyst exhibits the highest photodegradation efficiency because of its smaller interplanar spacing, formation of the midgap state, and adjustable local electron density. Equally, the doping of I atom not only provides a stable adsorption site for oxygen (O2) but also facilitates electron transfer, promoting the production of superoxide radicals (O2−) and contributing to the process of photodegradation.
