New Journal of Chemistry最新文献

Developing biodegradable light conversion films is of great significance in the agriculture and environment fields. In this work, two types of light conversion films were successfully prepared using biodegradable polylactide (PLA) and poly (butylene adipate-co-terephthalate) (PBAT) combined with different amounts of europium(III) complexes (0.1%,0.3%, and 0.5%) through solution casting. Europium(III) complexes were dispersed uniformly in PLA/PBAT, the hydrophilicity of the films increased with the addition of europium(III) complexes. The films with a light transmittance of up to 80% displayed excellent light conversion capabilities and could convert UV-vis light into red light. Meanwhile, the tensile strength and elongation at the break of the PLA/PBAT/0.5% europium(III) complex film reached 41.05 MPa and 19.29%, respectively. This work provides new ideas for research on degradable light conversion films.

In this study, we investigate the reactivity of nitrous oxide (N₂O) with lithiated diarylmethylhydrazines, leading to the formation of diarylethanes via dinitrogen extrusion. The reaction proceeds through the formation of a lithium oxytetrazene adduct generated by the interaction of the lithium salt of diarylmethylhydrazines with nitrous oxide. Upon heating at 60 °C, this adduct efficiently converts into diarylethane in good yields. Experimental data (IR, UV) and density functional theory (DFT) calculations support the formation of the lithium oxytetrazene intermediate, which subsequently eliminates lithium hydroxide and nitrogen gas, yielding diarylethane. This method demonstrates broad substrate tolerance, accommodating substituted hydrazines with both electron-donating and electron-withdrawing groups, as well as cyclic and unsymmetrical hydrazines.

1-Ethyl-3-methylimidazolium dinitramide (EMImDN), an energetic ionic liquid, was synthesized and characterized by IR, ¹H NMR, ¹³C NMR, ¹⁵N NMR, and ¹⁷O NMR techniques. The thermal properties of EMImDN were investigated through DSC and TG analyses. The TG curve revealed three consecutive exothermic decomposition events with peak temperatures at 223 °C, 277 °C and 308 °C, accompanied by an 80% mass loss between 180 °C and 280 °C. The thermal decomposition kinetics were analyzed using the Kissinger method and Flynn–Wall–Ozawa isoconversional method. The activation energies for the three decomposition stages were calculated to be 41.1, 35.9 and 43.2 kcal mol⁻¹ respectively by the Kissinger method and 39.0, 36.8 and 42.6 kcal mol⁻¹, respectively, by the FWO method. Pyrolysis GC-MS analysis identified the decomposition products, and the decomposition mechanism was predicted to involve dealkylation of the imidazole ring via bimolecular nucleophilic substitution (S_N2). The proposed decomposition mechanism was further supported by density functional theory (DFT) calculations at the B3LYP/6-311+G(d,p) level. Additionally, the molar enthalpy of formation of EMImDN (+54.5 kcal mol⁻¹), determined through combustion calorimetry, underscores the energetic nature of this ionic liquid. Notably, a 10 wt% solution of NH₃BH₃ in EMImDN exhibited hypergolicity with red fuming nitric acid. Preliminary investigations into the interactions of EMImDN with HNO₃ and NH₃BH₃ provide insights into the initial stages of this hypergolic reaction.

Folic acid (FA) is a crucial vitamin for human health, and imbalanced levels of folate can result in various illnesses. A new fluorescent probe called CQD–MSN, made from biomass carbon quantum dots and mesoporous silica, was developed through hydrothermal and template techniques to detect FA concentrations. By studying the fluorescence response and linear correlation of the CQD–MSN with FA, the optimal conditions were determined by adjusting the reaction time and pH level. The findings indicated that the best fluorescence quenching effect occurred when the pH was 7.4, and the reaction time was 4 min. At λ_ex = 355 nm and λ_em = 427 nm, the fluorescence emission spectra of CQD–MSN were notably reduced due to the combined effects of static quenching and internal filtering effect when FA was present. Under optimal conditions, the detection concentration for FA ranged from 0 to 100.0 μM, with a limit of 0.18 μM. Furthermore, CQD–MSN were effectively utilized to measure FA in real samples, including urine and rabbit serum, achieving spiked recoveries between 98.7% and 102.3%. These results demonstrated that CQD–MSN is a suitable tool for analysing FA in biosensing applications.

Designing benign catalytic systems is essential to accelerate polymerization research. This requires a thorough understanding of structural interactions between catalysts and monomers. We here report a combined approach involving bench experiments, density functional theory (DFT), and multivariate linear regression (MLR) to elucidate the structure–activity relationships of catalysts. Fluorophenol derived dual organocatalysts were designed and applied for ring-opening polymerization (ROP) of L-lactide (LLA), where the catalytic system exhibits high catalytic activity in bulk at 140 °C. Mechanistic studies revealed a synergistic catalytic process, where the dual organocatalysts activate the initiator and monomer through hydrogen bonding interaction. By applying a multivariate linear regression (MLR) model, the study identifies key electronic and thermodynamic descriptors that significantly influence the observed rate constants (k_obs) in the catalytic process.

Various pollutants in wastewater that are produced from industrial and domestic processes are causing huge threats to human health and environmental safety. Novel porous carbon materials with specially designed surface physiochemical characteristics and pore structures are considered one of the most potential candidates for the highly efficient removal of these pollutants via adsorption. In particular, they have the inherent characteristic of being positively charged towards cationic dyes and SARS-CoV-2 virus with the unique spike protein. Based on this, in this work, we proposed and developed a new strategy for surface-negative ζ potential engineering of porous carbon materials using Fenton reagent, which is a mild, eco-friendly but potent free radical provider. After the pretreatment with Fenton reagent, the amount of oxygen-containing functional groups increased considerably, followed by a distinct decrease in the ζ potential for the porous carbon materials, which, in turn, enabled a relatively higher binding force between the adsorbent and target adsorbate, resulting in the enhanced performance of porous carbon materials in the removal of methylene blue (585.1 mg g⁻¹) and SARS-CoV-2 virus-like-particles (98.61%, 50 g L⁻¹). Thus, this work not only highlights porous carbon materials as promising candidates for the removal of cationic dyes and viruses but also provides a universal strategy for producing negatively charged porous carbon materials with high feasibility and sustainability.

Three hexaphenylmelamine phosphors substituted with fluorine at meta, ortho, and para positions were synthesized and characterized, showing increasing phosphorescence lifetimes and quantum yields. Crystal analysis and theoretical calculations suggest that the superior RTP of HPM-p-F is attributed to its higher oscillator strength, increased molecular binding energy, and favorable spin–orbit coupling.

Hydrogen is considered a promising alternative to conventional fossil fuels, as it can be easily produced from renewable energy sources. While electrocatalytic water splitting can achieve near-unity faradaic efficiency in producing hydrogen from water, the widespread implementation of large-scale water electrolysis is hindered by reliance on costly platinum group metal-based electrocatalysts. Here, we report on the rational design of Molybdenum-containing SiCN composites (Mo–SiCN) through an active-filler controlled pyrolysis (AFCOP) strategy. Our investigation into the composite's microstructural evolution revealed the formation of a Mo_4.8Si₃C_0.6 Nowotny phase at a relatively low temperature of 1000 °C. After optimization, the resulting catalyst demonstrated a Tafel slope below 95 mV dec⁻¹ and an overpotential near 575 mV at a normalized current density of 1 mA μF⁻¹. As a proof of concept, the AFCOP strategy was employed to engineer a crack-free Mo–SiCN micropattern, enabling the miniaturization of a Pt-free electrochemical water splitting (EWS) reactor. Produced via soft lithography, the Mo–SiCN pattern exhibits feature sizes ranging from 10 to 200 μm, with near-net-shape replication and a Young's modulus of ≈60 GPa.

Herein, we report an efficient strategy for the synthesis of C4-functionalized novel Pfitzinger acid derivatives via C(sp³)–H bond functionalization. This approach capitalizes on the use of a deep eutectic solvent (DES) comprising N,N′-dimethyl urea and L-(+)-tartaric acid (3 : 1 ratio) at 80 °C as the reaction medium. The 1,2,3,4-tetrahydroacridine-based Pfitzinger acid and its derivatives (methyl/benzyl esters, amides, and Weinreb amides) were used for C4 functionalization with aromatic aldehydes. All the synthesized compounds were evaluated for their dual cholinesterase and α-glucosidase inhibitory activity. Most of the evaluated products showed significant inhibitory activity against AChE, BChE and α-glucosidase enzymes in comparison with standard drug tacrine (AChE IC₅₀ = 201.05 nM; BChE IC₅₀ = 202.14 nM) and acarbose (IC₅₀ = 23 124 nM). Among the tested compounds, 6f showed inhibitory activity with IC₅₀ = 119.45 nM (for AChE) and IC₅₀ = 121.58 nM (for BChE), 6v showed inhibitory activity with IC₅₀ = 121.87 nM (for AChE) and IC₅₀ = 118.25 nM (for BChE) and 9g inhibitory activity against α-glucosidase with IC₅₀ = 21 442 nM. The docking and kinetic studies supported the experimental results obtained through in vitro experiments and predicted drug-like properties.

The pathogenesis of Alzheimer's disease is very complex, so its multifunctional treatment is of great significance, in which the synergistic therapy of the amyloid cascade hypothesis and oxidative stress hypothesis shows good results. In this study, bifunctional carbon dots (CACDs) that can inhibit amyloid aggregation and relieve oxidative stress were synthesized. Studies have shown that CACDs have a good antioxidant effect. When the concentration of CACDs is 100 μg mL⁻¹, the elimination efficiency of DPPH (2,2-diphenyl-1-picrylhydrazyl) reaches 65.57%, and the scavenging efficiency of ˙O₂⁻ and ˙OH reaches 79.6% and 73.9%, respectively. Moreover, CACDs possess outstanding scavenging abilities against the ROS in cells, thus resulting in the mitigation of cellular oxidative damage. Meanwhile, CACDs can also bind to lysozyme proteins through hydrophobic interactions to further interfere with the amyloid self-assembly process. According to thioflavin T (ThT) analysis, the inhibition efficiency of CACDs on amyloid proteins gradually increases with increasing concentration. Circular dichroism spectroscopy (CD) further indicates that the CACDs can inhibit the transition of the protein structure to the β-sheet structure. CACDs and Aβ₄₂ also have strong binding ability. CACDs have excellent biocompatibility and can alleviate the cytotoxicity caused by Aβ oligomers. The results demonstrate that CACDs have promising applications in multifunctional materials and important applications in multi-target therapy of Alzheimer's disease.