Chemistry Letters

Abstract In this study a new oligomeric DOPO-containing compound with flame retardant properties was obtained based on polyethyleneimine (PEI). The oligomer was synthesized using the following components: polyethyleneimine, benzaldehyde, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). The PEI-based flame retardant in an amount of 8% by weight was incorporated into the polymer matri…

Abstract Al environment in zeolites is one of the crucial factors determining their application performance. Although various strategies have been explored to control the Al environment, significant challenges remain in optimizing the synthesis conditions. Here, we report a postsynthetic approach for tuning the Al environment of FAU-type zeolite through hydrothermal treatment in the presence of f…

Abstract Lean-burn engines emit low CO2, but produce high NOx, and conventional three-way catalysts cannot purify NOx from oxygen-rich exhaust gases. NOx storage reduction (NSR) is effective but typically requires fuel-consuming “rich spikes”. We investigated an NSR process in an electric field, achieving effective NOx reduction under low-temperature (473 K) lean conditions. We developed a 0.1wt%…

Abstract Ba0.5Ca0.5F2 is a fluoride-ion conductor expected to be used in next-generation fluoride-ion batteries. We examined the local structures around Ba and Ca using K-edge X-ray absorption fine structure (XAFS) spectroscopy. Compared with pure BaF2 and CaF2, the local structures around both Ba and Ca are highly disordered in Ba0.52Ca0.48F2. The Ba–F and Ca–F bond lengths, which retain almost …

Abstract Traditional medicinal plants remain an important source of bioactive natural products. However, classical phytochemical discovery is increasingly limited by plant selection uncertainty, labor-intensive workflows, and frequent rediscovery. Recent advances emphasize integrative strategies that combine ethnopharmacological knowledge with modern analytical, metabolomics, molecular networking…

Abstract Styrene was polymerized by soap-free emulsion polymerization in water in the presence of an organic solvent to form polystyrene (PSt) nanoparticles containing the solvent. Thermal annealing under reflux produced particles with core–shell contrast in TEM, indicating radial redistribution of polymer mass. The core size depended on solvent type, while a higher initiator/monomer ratio reduce…

Abstract Single-walled carbon nanotubes (SWNTs) exhibit chirality-dependent near-infrared photoluminescence (PL) sensitive to their chemical environment. We investigated time-dependent PL responses of DNA-dispersed SWNTs upon the addition of 4 enzymes with distinct properties. Proteolytic enzymes with free cysteine residues (bromelain and ficin) and carbohydrate-hydrolyzing enzymes containing onl…

Abstract Oxygen vacancies were introduced into CaCu3Ti4O12 using bisphenol A to enhance its UV-driven photodegradation of methylene blue. Structural and spectroscopic analyses confirmed successful vacancy formation. Radical trapping identified ·OH as a key species. Optimized samples achieved 84.68% removal (0.0061 min−1), far exceeding pristine CaCu3Ti4O12 (32.78%), via oxygen vacancies. This wor…

Abstract We introduce an indirect electrochemical synthesis approach for imine-bonded COF films, using electrogenerated acid as a catalyst. A simple and tunable electrolysis system yields COF or its intermediate film under ambient conditions within minutes, and is broadly applicable across versatile monomers. Several applications based on the higher-order structures are also demonstrated.

Abstract Au/ZrO2 exhibits catalytic activity for propylene epoxidation; however, its catalytic performance is relatively lower than that of Au/TiO2. To clarify the origin of this support dependence, we investigated the reaction mechanism of propylene epoxidation over Au/ZrO2 using first-principles calculations. Our study revealed that the active species was a peroxide intermediate, Zr–OOH. Furthe…

Abstract Despite its higher oxidation potential, Bu3SnCl has been found to be a more effective Bu-transferring reagent than Bu4Sn in the photo-induced reaction of benzil in benzene. The attractive interaction between Bu3SnCl and benzil, especially in benzene, is a presumable reason for its higher reactivity. In contrast, Bu2SnCl2 and BuSnCl3 are poorly reactive in such a photoreaction.

Abstract The effects of reaction vessel scale and argon (Ar) gas pressure on the overall water splitting catalyzed by directly connected silver vanadate (Ag2V4O11) and zinc rhodium oxide (ZnRh2O4), i.e. Ag2V4O11/ZnRh2O4, were systematically investigated. Scaling up the reaction vessel 10-fold resulted in marked 30-fold increases in hydrogen (H2) and oxygen (O2) evolution rates, which were attribu…

Abstract Laser-induced microbubbles generated by photothermal effects in aqueous solutions have been widely studied, but the chemical characterization of microbubbles in non-aqueous systems remains limited. This study, therefore, focused on the temperature dependence of lithium chloride (LiCl) dissolution in tetrahydrofuran (THF) and investigated the properties exhibited by the microbubbles in TH…

Abstract A polyurethane soluble in organic solvents was synthesized via polyaddition of dicyclohexylmethane-4,4′-diisocyanate with a newly designed diol monomer containing 2-(3,5-dialkynyl-2-hydroxyphenyl)-5-tert-pentylbenzoxazole as an excited-state intramolecular proton transfer (ESIPT) luminophore. The resulting polyurethane is amorphous with a high glass transition temperature of 164 °C. Spin…

Abstract This research investigated the fabrication of face-to-face tandem solar cells using vacuum lamination to combine a normal-structure top cell with an inverted-structure bottom cell through organic recombination layers. Using carbon nanotubes, the tandem solar cell achieved a power conversion efficiency (PCE) of 2.2%, and additional graphene layers improved the interfacial contact, enhanci…

Abstract We developed a collagen microfiber-based 3D cancer tissue model that included monocytes. Using a sedimentation culture method, normal human dermal fibroblasts, endothelial cells, cancer cells, and THP-1 cells—that is, the human monocytes cell line—were cocultured under a high collagen density. THP-1 cells were differentiated into macrophages and showed M2-like polarization in the 3D tumo…

Abstract A pair of chiral molecular glasses has been created and the hybrid fibers composed of the photochromic molecular glass with the created chiral molecular glass were found to exhibit novel chiral photomechanical motions. The hybrid fibers exhibited photomechanical bending, and the bending direction was not straight relative to the incident beam but was deflected. When the chirality of the …

Abstract Human erythrocyte band 3 is an anion exchanger composed of 14 transmembrane segments (TMs). Its function is inhibited by the modification of Lys-539 on TM 5 using 4,4′-diisothiocyanatodihydrostilbene 2,2′-disulfonate (H2DIDS). Upon the exposure of band 3 to alkaline pH, another isothiocyanate group of H2DIDS can react with Lys-851 on TM 13. Thus, Lys-539 on TM 5 and Lys-851 on TM13 are c…

Abstract A molecular beacon-based platform that enables the switchable, DNA-structure-dependent generation of singlet oxygen ( 1O2) was designed. We prepared stem-and-loop structured oligodeoxynucleotides with an excellent photosensitizer, ruthenium complex, and cyclooctatetraene quencher attached at each strand end. The stem-and-loop structured oligodeoxynucleotides suppressed the photosensitize…

Abstract Ammonia is attracting attention as a carbon-free hydrogen carrier with high hydrogen content and good handling properties, although its endothermic decomposition requires high temperatures (>773 K). We previously achieved nearly complete ammonia conversion even at 398 K via an electric field (EF)-assisted catalytic reaction, in which hydrogen conduction on the catalyst surface (i.…