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The accumulation of polyethylene terephthalate (PET) and polyamide 66 (PA66) in municipal and industrial waste streams represents a major challenge to global sustainability efforts. In this work, we report the development and optimization of a low-cost, iron-recoverable, and reconstitutable Lewis–Brønsted aqueous solution (LBAS) system for the selective depolymerization of post-consumer PET and PA66 wastes. The method employs a recyclable reaction medium and operates under mild conditions (150 °C, 2 h), achieving high monomer yields with excellent selectivity. The resulting terephthalic acid, adipic acid, and hexamethylenediammonium chloride were efficiently recovered and purified using straightforward separation techniques, whereas ethylene glycol was recovered as a stream suitable for purification by conventional industrial methods. A proof-of-concept experiment confirmed that PET and PA66 can also be depolymerized in the same medium, even though cross reactions between adipic acid and ethylene glycol prevent the quantitative monomer recovery. Therefore, mixed PET/PA66 feeds require prior separation to recover the individual monomers effectively. Overall, results demonstrate a scalable and environmentally benign approach for the chemical recycling of PET and PA66, contributing to a more sustainable plastic lifecycle and circular materials economy.

Flavonoid–oxidovanadium(IV) (VO) complexes have been widely investigated as anticancer agents because of their ability to induce oxidative stress in tumor cells. In contrast, Zn complexes with ligands capable of reducing intracellular reactive oxygen species (ROS) may exert antitumor effects through a reductive-stress mechanism. Herein, we report the synthesis and characterization of a Zn–troxerutin complex, its interaction with bovine serum albumin (BSA), and its anticancer activity. This study aims to correlate the chemical and biological properties of the complex after replacing a redox-active metal ion with a redox-inactive one. The Zn–troxerutin complex exhibited the same coordination mode and 1:1 metal-to-ligand stoichiometry as the VO analog. It showed dose-dependent antiproliferative activity at higher concentrations in A549, MDA-MB-231, and HCT-116 cancer cells, while reducing intracellular ROS. In HCT-116 cells, reductive stress was associated with increased glutathione (GSH) levels and mitochondrial membrane depolarization. The complex displayed greater anticancer efficacy than free troxerutin and selectivity toward cancer cells over normal HEK293 cells. BSA binding studies yielded positive ΔH and ΔS values, indicating that hydrophobic interactions drive complex formation, with binding constants within the optimal range for drug transport. These findings highlight Zn–troxerutin as a promising anticancer agent acting through reductive-stress pathways.

Passive permeation across biological membranes is governed by a delicate balance of transient noncovalent interactions that are difficult to resolve experimentally or through conventional molecular dynamics (MD) analyses alone. Here, we present a perspective on the integration of the averaged modified independent gradient model (amIGM) based on promolecular density approximation and the graphic representation of the local electron energy density (GLED) with classical MD simulations to investigate the passive translocation of the cisplatin (cisPt) anticancer drug across a model membrane representative of the lipid composition of breast cancer cells. This multiscale framework combines atomistic sampling with real-space descriptors, enabling the dynamic characterization of hydrogen bonding, dispersion forces, steric effects, and local electronic stabilization trends along the permeation pathway. As a proof of concept, we analyze the supramolecular nanosolvation environment of cisPt at finite temperature in two representative states: bulk aqueous solution and membrane center, corresponding to the maximum of the potential of mean force (+16 kcal mol⁻¹). The combined amIGM/GLED approach reveals how the nature and spatial distribution of drug–water interactions evolve in response to the local membrane environment, providing mechanistic insight into the electronic and supramolecular factors that shape the free-energy landscape of passive permeation.

2,3-Dicyanopyrazine (DCNP) was first utilized as a π-acceptor to form charge-transfer complexes with strong π-donors, 3a,6a-diaza-1,4-diphosphapentalenes (RR’DDP), bearing peripheral methyl and annelated cyclohexyl substituents. The donor and acceptor molecules form mixed D–A–D–A stacks irrespective of the component ratio. The study of electron density topology indicated that each DCNP molecule accepts 0.22–0.24 electron charges in the crystal. The intermolecular interaction energy between donor and acceptor molecules ranges from 3.8 to 5.0 kcal/mol. An evaluation of the dark conductivity of the (cHexDDP•DCNP) sample showed an increase in current by ~5 orders of magnitude upon raising the temperature from 233 to 283 K. When RR’DDP interacts with acenaphthene- and cyclohexane-annelated 2,3-dicyanopyrazines, complexation is observed in solution, but CTC crystals do not form.

The development of efficient catalytic strategies for the chemical recycling and upcycling of poly(lactic acid) (PLA) is of great importance for advancing sustainable polymer technologies and promoting a circular plastics economy. Herein, we describe the selective alcoholysis of PLA promoted by a commercial titanium alkoxide and a phenoxy-imine pyridine zinc complex using various diols, leading to the formation of novel lactyl-based intermediates that were employed in subsequent polycondensation reactions with dicarboxylic acids. Alcoholysis reaction of PLA in the presence of ethylene glycol, 1,4-butanediol, cis-2-butene-1,4-diol and 3-allyloxy-1,2-propanediol afforded novel lactyl-containing diols, which were successfully reacted with adipic acid to produce a series of novel copolyesters. Structural characterization by one- and two-dimensional NMR spectroscopy confirmed the effective incorporation of lactyl units into the polymer backbones. Thermal analyses revealed that the introduction of lactyl moieties influences the crystallinity and thermal behavior of the resulting materials, generally leading to amorphous polymers. This approach demonstrates a straightforward and versatile route for the valorization of PLA waste into novel functional building blocks for the synthesis of potentially biodegradable polyesters with a variety of chemical features.

Benzaldehyde is a vital intermediate for the synthesis of pharmaceuticals and agrochemicals. Traditional chemical synthesis methods are costly and cause environmental pollution. Therefore, developing novel green synthesis approaches is growing increasingly important. A photoelectrochemical (PEC) system was constructed using a WO₃/SnO₂ n–n heterojunction photoanode, with N-hydroxysuccinimide (NHS) acting as a selective hydrogen-atom-transfer mediator. The preparation parameters were optimized, and the material was characterized by SEM, TEM, XRD, XPS, and UV–vis diffuse reflectance spectroscopy. PEC properties and catalytic performance were evaluated. The optimized WO₃/SnO₂ exhibited extended light absorption and efficient charge separation. Under ambient conditions, the PEC system delivered 98% yield and 100% selectivity for benzaldehyde without using hazardous oxidants or causing substrate overoxidation. This work provides a green and efficient approach for benzaldehyde synthesis, offering theoretical and technical support for the PEC production of high-value fine chemicals and pharmaceutical intermediates.

This study presents an integrated, waste-based route to produce chemically purified cellulose (CPC), cellulose nanofibers (CNF), cellulose nanocrystals (CNCs), and carbon dots (CDs) from Tectona grandis (teak) leaves. CPC was obtained by sequential dewaxing, chlorite bleaching, sulfite treatment, and alkaline extraction. CNFs were prepared by high-shear processing and sonication, while CNCs were produced by controlled sulfuric-acid hydrolysis. CDs, including sulfur- and nitrogen-doped variants, were synthesized via hydrothermal carbonization of leaf powder. Materials were characterized by proximate/ultimate (elemental) analysis, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), atomic force microscopy, UV–vis/fluorescence spectroscopy, dynamic light scattering/zeta potential (ζ), and thermogravimetric analysis (TGA). Proximate/ultimate analysis indicates the leaves are a suitable feedstock (C ≈ 40.42 wt%, holocellulose ≈ 42.19 wt%, α-cellulose ≈ 18.18 wt%). XRD analysis yields a CNC crystallinity index of ≈63.19%. Microscopy confirms rod-like CNC morphology and nanoscale CDs. TGA shows thermal behavior consistent with a stable cellulose fraction, and preliminary antibacterial testing (Escherichia coli) was performed using the pour-plate method. The presented water-based procedures convert a combustible forest residue into value-added nanomaterials.

Advanced oxidation processes are among the mainstream and high-efficiency technologies for treating pharmaceutically active compounds and other water pollutants. However, most current electro-Fenton (EF) processes still rely on the use of Fe²⁺ and oxidizing agents, and the secondary pollution problem caused by metal ion leaching resulting therefrom has not yet been effectively addressed. Herein, we report a dual-system four-electrode EF cell that requires no addition of chemical reagents. The system employs a 300-nm-thick NiFeMnCu (NFMC) thin film, which not only functions as an OER collector for oxygen generation from both Anode I and Anode II, but also serves as a working electrode with a two-electron pathway to produce H₂O₂ through the electrochemical reduction of O₂ at Cathode I. Furthermore, by integrating the Cathode II, NFMC cathode for the second-step sequential electrocatalytic reaction, the generation of H₂O₂ and its conversion to ·OH can be achieved. This catalytic system can effectively avoid problems such as metal sludge accumulation. When cefadroxil is used as the target pollutant, its removal can be completed within 30 min. Owing to the adoption of low-cost, durable, and scalable electrode materials, this process possesses high feasibility for practical application.

Dye-sensitized solar cells are gaining recognition as a promising technology increasingly drawing the interest of a burgeoning array of IoT devices and wireless sensors, providing a solution to the escalating need for cordless power. We have chosen four organic sensitizers incorporating triphenyl imidazole and phenothiazine as double donors alongside a carboxylic acid as an anchoring group. Sensitizers have either benzothiadiazole (LG-P6 and LG-P8) or phenyl (LG-P5 and LG-P6) as an auxiliary acceptor, separated from the anchoring carboxylic acid group by an ethynyl bridge. The devices are fabricated using the I^-/I₃ ^- redox couple and evaluated under AM1.5G and indoor light conditions. The sensitizers having benzothiadiazole displayed efficiency of 5.98% and 2.81% under 1-sun conditions. Further, we have systematically evaluated device performance from 1000 to 100 lx WW CFL, WW LED, DL CFL, and DL LED light conditions. We observed efficiencies of 19.73% under 1000 lx WW CFL and 24.23% under 100 lx WW LED conditions using the LG-P6 sensitizer, which is one among the highest efficiencies reported without cosensitization to the best of our knowledge. Further, we adopted interfacial charge transfer studies using different perturbation techniques to explain the photovoltaic results.

One of the most important processes in creating sustainable monomers for high-performance polymers is the catalytic dehydration of sorbitol obtained from biomass to isosorbide. This study investigated a series of sulfated Zr_xSn_{1 - x}O₂ (x = 0.1-0.9) mixed oxides prepared by coprecipitation method for sorbitol dehydration under solvent-free conditions. Comprehensive evaluation of different characterization techniques, i.e., X-ray diffraction, Fourier transform infrared, transmission electron microscope, N₂ physisorption, and NH₃-TPD demonstrated that surface acidity, textural characteristics, and catalytic activity were greatly affected by catalyst composition. Catalyst with intermediate Zr content (0.4-0.6) had an ideal balance of weak, medium, and strong Brønsted acid sites, which resulted in complete conversion of sorbitol and higher isosorbide selectivity. 100% sorbitol conversion and 87% isosorbide selectivity were achieved with sulfated (S)-Zr_0.5Sn_0.5O₂ at 220 °C within 3 h, exceeding many reported heterogeneous solid acids catalyst. A minor loss in catalyst activity was observed after four cycles, showing its potential for long-term isosorbide production.