Latest ArticlesLn-containing polyoxoniobates (PONbs) have appealing applications in luminescence, information encryption and magnetic fields, but the synthesis of PONbs containing high-nuclearity Ln-O clusters is challenging due to the easy hydrolysis of Ln3+ ions in alkaline environments. In this paper, we are able to integrate CO32− and high-nuclearity Ln-O clusters into PONb to construct an inorganic giant Eu19-embedded PONb H49K16Na13(H2O)63[Eu21O2(OH)7(H2O)5(Nb7O22)10(Nb2O6)2(CO3)18]·91H2O (1), which contains the highest nuclearity Eu-O clusters and the largest number of Eu3+ ions among PONbs. In addition, the film that was prepared by mixing 1 with gelatin and glycerol, exhibits reversible luminescence switching behavior under acid/alkali stimulation and has been used to create a fluorescence-encoded information approach. This work paves a feasible strategy for the construction of high-nuclearity Ln-O cluster-containing PONbs and the expansion of the application of Ln-containing PONbs in information encryption.
In this paper, low-temperature dielectric-blocked discharge plasma (DBD) was employed for the first time to treat silica-doped H4PMo11VO40 (HPAV) catalysts (DBD(Ar/x)-MF-Catal) and apply them in the catalytic methacrolein (MAL) selective oxidation to produce methacrylic acid (MAA). This work investigates in detail the controllable regulation of the concentration of oxidation states on silica-doped HPAV catalysts by adjusting the DBD discharge with controlled changes in voltage, current, treatment time, and treatment medium. It reports the intrinsic correlation between oxidation states and MAL oxidation performance. The research results indicated that the catalytic performance was related to the presence of oxygen vacancies and oxygen species (VO2+), and are the main reason for the selective oxidation of MAL to MAA. Besides, the generation of oxygen vacancies and VO2+ altered localized electrons, which resulted in the easier activation of O2. Theoretical calculations of DFT also proved the formation mechanism of oxygen vacancies and VO2+ and electron properties on high-performance polymers, which elucidated the intrinsic influence of catalyst components. The DBD(Ar/10)-MF-Catal catalysts with suitable VO2+ and oxygen vacancy concentrations exhibited the highest catalytic performance with 90% MAL conversion and 70% MAA selectivity and showed good stability (500 h).
Developing a heterostructure for alloying-based anode for sodium-ion batteries (SIBs) is an efficient solution to accommodate volume change upon sodiation/desodiation and boost sodium storage since it combines the merits of each component. Herein, we report a metallic and microphone-like Sn-Zn0.9Mn0.1O heterostructure via an in-situ Mn doping strategy. Based on theoretical calculations and experimental results, the introduction of Mn into ZnO (a small amount of Mn also diffuses into the Sn lattice) can not only enhance intrinsic electronic conductivity but also reduce the Na+ diffusion barrier inside the Sn phase. When evaluated as anode for SIBs, the obtained heterostructures show a high reversible capacity of 395.1 mAh/g at 0.1 A/g, rate capability of 332 mAh/g at 5 A/g, and capacity retention of almost 100% after 850 cycles at 5 A/g, indicating its great potential for high-power application of SIBs.
Optimizing the interfacial quality of halide perovskites heterojunction to promote the photogenerated charge separation is of great significance in photocatalytic reactions. However, the delicately regulation of interfacial structure and properties of halide perovskites hybrid is still a big challenge owing to the growth uncontrollability and incompatibility between different constituents. Here we use BiOBr nanosheets as the start-template to in situ epitaxially grow Cs3Bi2Br9 nanosheets by “cosharing” Bi and Br atoms strategy for designing a 2D/2D Cs3Bi2Br9/BiOBr heterojunction. Systematic studies show that the epitaxial heterojunction can optimize the synergistic effect of BiOBr and Cs3Bi2Br9 via the formation of tight-contact interfaces, strong interfacial electronic coupling and charge redistribution, which can not only drive the Z-scheme charge transfer mechanism to greatly promote the spatial separation of electron-hole pairs, but also modulate the interfacial electronic structure to facilitate the adsorption and activation of toluene molecules. The heterojunction exhibited 62.3 and 2.4-fold photoactivity improvement for toluene oxidation to benzaldehyde than parental BiOBr and Cs3Bi2Br9, respectively. This study not only proposed a novel dual atom-bridge protocol to engineer high-quality perovskite heterojunctions, but also uncovered the potential of heterojunction in promoting electron-hole separation as well as the application in photocatalytic organic synthesis.
Core-shell colloidal particles with a polymer layer have broad applications in different areas. Herein, we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer (RAFT) polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer layer. Chemical compositions, structures, and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed [monomer]/[chain transfer agent] ratios during seeded RAFT polymerization.
The first synthesis of flavanostilbenes with a 2-cyclohepten-1-one core was carried out by applying an effective strategy in three steps from abundant polymerized flavanol resources. A key regio- and stereoselective Cu-mediated [5 + 2] cycloaddition/decarboxylation cascade was explored and applied without the use of protecting groups, and water as an environmentally friendly solvent contributed to the cascade. The intramolecular [5 + 2] cycloaddition mechanism, involving oxidation and dearomatization of the flavanol unit as a diene, was proposed and supported by the synthesis of the intermediate. The regioselectivity of the cyclization was found to be dependent on the substitution effects of the stilbene units by the exploration of substrate scope.
The complexity of living environment system demands higher requirements for the sensitivity and selectivity of the probe. Therefore, it is of great importance to develop a universal strategy for high-performance probe optimization. Herein, we propose a novel “Enrichment-enhanced Detection” strategy and use carbon dots-dopamine detection system as a representative model to evaluate its feasibility. The composite probe carbon dots (CDs)-encapsulated in glycol-chitosan (GC) (i.e., CDs@GC) was obtained by simply mixing GC and CDs through noncovalent interactions, including electrostatic interactions and hydrogen bonding. Dopamine (DA) could be detected through internal filter effect (IFE)-induced quenching of CDs. In the case of CDs@GC, noncovalent interactions (electrostatic interactions) between GC and the formed quinone (oxide of DA) could selectively extract and enrich the local concentration of DA, thus effectively improving the sensitivity and selectivity of the sensing system. The nanosensor had a low detection limit of 3.7 nmol/L, which was a 12-fold sensitivity improvement compared to the bare CDs probes with similar fluorescent profiles, proving the feasibility of the “Enrichment-enhanced Detection” strategy. Further, to examine this theory in real case, we designed a highly portable sensing platform to realize visual determination of DA. Overall, our work introduces a new strategy for accurately detecting DA and provides valuable insights for the universal design and optimization of superior nanoprobes.
Cholelithiasis affects approximately 10%-20% of the adult population globally. And cholesterol accumulation and nucleation of cholesterol crystals are commonly recognized as the primary process in the initiation and progression of gallstones. Hydroxypropyl-β-cyclodextrin (HPCD) is a supramolecular host compound that can solubilize cholesterol, potentially serving as a preventative or therapeutic agent for cholelithiasis. However, we found that the administration of HPCD treatment did not impede the formation of gallstones in mice, mainly attributed to the pre-complexation of its cavity during the transition process. Here we synthesized a prodrug of HPCD and prepared a HPCD nanoparticle (HPCD-NP), which can be transported efficiently to the gallbladder through the hepatobiliary system following an intravenous injection. In the bile, the HPCD-NP degraded into free HPCD, bound to cholesterol crystals and gallstones within the gallbladder and effectively increased cholesterol solubilization, leading to gallstones regression. Given the established safety of both HPCD and cyclodextrin-based nanoparticles in numerous animal and human studies, HPCD-NP shows considerable promise for the prevention and treatment of human cholelithiasis.
Nor-seco-cucurbit[10]uril (ns-CB[10]) is a kinetic product with unique structure. The single bridged methylene in its structure makes the molecular cavity of ns-CB[10] more deformable when compared to ordinary cucurbit[n]uril, reducing its structural stability. Repeated experiments showed that ns-CB[10] gradually cracks in an acidic solution and changes the specificity of cucurbit[5]uril (CB[5]) and cucurbit[8]uril (CB[8]) under more robust acidic solutions and when heated. A series of experiments were designed to study the transformation behavior of ns-CB[10]. It was found that the concentration of ns-CB[10] was correlated with the content distribution of CB[5] and CB[8]. This study explores the influencing factors and mechanisms of the transformation of ns-CB[10] to CB[5] and CB[8]. The results are of great significance for the application of ns-CB[10], understanding the formation mechanism of cucurbit[n]urils. Furthermore, it provides a new pathway for synthesizing new cucurbit[n]urils.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
