Latest ArticlesCharge-transfer complexes (CTCs) have emerged as promising n-type organic thermoelectric (TE) materials due to their inherent high electrical conductivity and tunable transport polarities. In this study, we performed a comprehensive first-principles investigation on the TE properties of nine CTCs comprised of 2,7-dialkyl[1]benzothieno[3,2-b][1]benzothiophenes (CnBTBT, n = 4, 8, 12) as donors and fluorinated derivatives of tetracyanoquinodimethane (FmTCNQ, m = 0, 2, 4) as acceptors, aiming to identify high-performance n-type organic TE materials and elucidate the underlying structure–property relationships. Our calculation results, based on the Boltzmann transport equation and deformation potential theory, reveal that the length of the alkyl side chains and the number of fluorine substitutions significantly impact their electronic structures and TE properties. Notably, the CnBTBT–FmTCNQ CTCs with shorter alkyl chains and more fluorine substitution demonstrate superior n-type characteristics, particularly C4BTBT–F4TCNQ, which achieves an excellent power factor of 671 µW cm-1 K-2 at an optimal charge carrier concentration. Our findings not only clarify the critical role of molecular engineering in CTC-based TE materials but also provide valuable guidance for developing high-efficiency organic TE materials with versatile practical applications.
We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl (R)-pantothenate ((R)-PaOEt), the direct precursor of D-pantothenic acid. Firstly, a ketoreductase mutant designated as M2, carrying two-point mutations of F97L and M242F relative to the wild-type SSCR, was constructed by site-directed mutagenesis, exhibited simultaneously improved activity toward ethyl 2′-ketopantothenate (K-PaOEt) and isopropanol, and could effectively catalyze the stereoselective reduction of K-PaOEt to (R)-PaOEt by using isopropanol as the sacrificial co-substrate to regenerate NADPH. After screening six commercially available carriers, an amino resin LXTE-700 was identified as the best solid support for the immobilization of M2 via the glutaraldehyde activation method. Upon optimization of the immobilization process and reaction conditions, the fabricated immobilized enzyme M2@amino resin demonstrated excellent recyclability and reusability, with the complete conversion of K-PaOEt to (R)-PaOEt being still realized after 12 cycles of reuse. Finally, M2@amino resin-catalyzed synthesis of (R)-PaOEt was successfully implemented in continuous-flow, accomplishing a 6.3 times higher space-time yield than that with the batch synthesis (529.2 versus 84 g L-1 d-1). Our developed flow biocatalysis system also features an outstanding operational stability, as evidenced by the 100% conversion rate achieved after 15 consecutive days of operation.
Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science. Recently, supramolecular polymeric materials (SPMs) have drawn increased attention due to their unique properties and potential applications in self-healing, shape memory, sensors, and flexible electronics. Here, we develop an ionic cluster-optimized microphase separation strategy to enhance the toughening and energy dissipation capabilities of polydisulfide-based supramolecular polymers. The mechanical properties, including Young’s modulus and toughness, are significantly improved by integrating the quadruple H-bonding 2-ureido-4-pyrimidone (UPy) induced microphase separation with iron(Ⅲ)-to-carboxylate ionic clusters. By combining established chemical approaches with adjustable polymer phase ratios, it is revealed that the synergistic effect of these factors expands the interchain spacing, facilitates the formation of microphase domains, and enhances the tolerance of polythioctic acid-based polymers to external mechanical and thermal stimuli, meeting the practical requirements for industrial plastic applications. Moreover, the UPy-functionalized polymers incorporating iron carboxylate clusters exhibit good one-way shape memory behavior with practical applicability at a relatively low recovery temperature. Our work demonstrates a novel strategy for constructing industrially viable shape memory dynamic SPMs and paves the way for future innovations in developing SPMs.
As a common electronic adhesive, ultraviolet (UV) curing polyurethane acrylate adhesive has both flexibility and wear resistance of polyurethane, excellent weather resistance and optical properties of acrylate. Despite the extensive applications, it is still difficult to solve the problems caused by the shrinkage of adhesive. Here, a new type of photosensitive adhesive for bonding electronic components based on supramolecular interaction was designed and synthesized. The supramolecular interaction of cyclodextrin and adamantane moieties introduced into the adhesive polymer entitles the viscosity of the adhesive to rise rapidly during use, thereby preventing adhesive loss and dislocation of electronic components. UV light could further cure the adhesive and position the electronic components. The adhesive shrunk < 2% when cured by UV light, so it can be used for electronic packaging and high-resolution, defect-free lithography.
Carbon dots (CDs), a class of emerging fluorescent nanomaterials, have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties, excellent biocompatibility, and ease of synthesis and functionalization. Recently, numerous CDs have been developed that allow precise subcellular localization through surface modifications or covalent conjugation with targeting ligands such as peptides, small molecules, Golgi-specific agents, and cell membrane-specific agents. This review begins with an overview of the synthesis strategies of CDs, highlighting their exceptional optical properties, stability, biocompatibility, and significance for subcellular imaging. The mechanisms by which CDs target specific organelles, including the nucleus, mitochondrion, lysosomes, Golgi apparatus, and cell membrane, are discussed. These mechanisms include specific targeting molecules, pH-sensitive targeting, charge-driven interactions, and hydrophobic and hydrophilic dynamics. Furthermore, we summarize their applications in subcellular imaging, such as the long-term dynamic monitoring of organelles, sensing, reactive oxygen species scavenging, and therapy. By presenting a comprehensive review of CDs in subcellular imaging, we aim to pave the way for further development of CDs in bioimaging and related biomedical applications.
Shape memory polymers used in 4D printing only had one permanent shape after molding, which limited their applications in requiring multiple reconstructions and multifunctional shapes. Furthermore, the inherent stability of the triazine ring structure within cyanate ester (CE) crosslinked networks after molding posed significant challenges for both recycling, repairing, and degradation of resin. To address these obstacles, dynamic thiocyanate ester (TCE) bonds and photocurable group were incorporated into CE, obtaining the recyclable and 3D printable CE covalent adaptable networks (CANs), denoted as PTCE1.5. This material exhibits a Young’s modulus of 810 MPa and a tensile strength of 50.8 MPa. Notably, damaged printed PTCE1.5 objects can be readily repaired through reprinting and interface rejoining by thermal treatment. Leveraging the solid-state plasticity, PTCE1.5 also demonstrated attractive shape memory ability and permanent shape reconfigurability, enabling its reconfigurable 4D printing. The printed PTCE1.5 hinges and a main body were assembled into a deployable and retractable satellite model, validating its potential application as a controllable component in the aerospace field. Moreover, printed PTCE1.5 can be fully degraded into thiol-modified intermediate products. Overall, this material not only enriches the application range of CE resin, but also provides a reliable approach to addressing environmental issue.
Cyclo[n]Thiophenes (CnTs) are a distinctive class of π-conjugated macrocyclic molecules that have attracted growing attention owing to their structural aesthetics and organic electronic characteristics. However, the development of CnTs has been largely impeded by inefficient synthetic route. In this work, we employ a bridge strategy using bipyridine as bridge to link two quaterthiophene units resulting in Φ-shaped bicyclosystem. This strain-retaining approach improves the synthesis efficiency of the macrocycles. Two new macrocyclic molecules, (4T-2hexyl-2Me)2-DPBP and (4T-2hexyl)2-DPBP, were successfully synthesized in total yield 17% and 16%, respectively. Single-crystal structure of (4T-2hexyl-2Me)2-DPBP reveals that the bipyridine bridge is orthogonally strapped by two quaterthiophene units. Notably, both compounds exhibit aggregation-induced emission enhancement (AIEE) behavior-an unprecedented feature among CnT-based macrocycles. Theoretical calculations reveal that this AIE phenomenon originates from the restriction of intramolecular motion (RIM) in the aggregated state, which suppresses the non-radiative decay channels. These results demonstrate a generalized strategy for the synthesis of functional π-conjugated macrocyclic molecules based fluorescent materials.
In 2024, the MOE Key Laboratory of Macromolecular Synthesis and Functionalization at Zhejiang University continued its impactful researches across five core areas. In controllable catalytic polymerization, organoboron catalysts were developed for CO2 copolymerization and novel photoresist materials. Studies in microstructure and rheology elucidated universal deformation modes in graphene-based 2D membranes and improved graphene fiber properties through shear alignment engineering, defect control, and enhanced interlayer entanglement. For separating functional polymers, Janus membranes and channels were created for multiphase separation, liquid-phase molecular layer-by-layer deposition technique was developed to fabricate aromatic polyamide nanofilms, and the harmonic amide bond density was established as a valuable parameter for polyamide structural analysis. In biomedical functional polymers, a sustainable carboxyl-ester transesterification strategy was proposed for upcycling poly(ethylene terephthalate) (PET) waste into biodegradable plastics. Additionally, immunocompatible biomaterials were designed utilizing zwitterionic polypeptides and albumin-derived coatings, and Cu2+-phenolic nanoflower was designed to combat fungal infections by combining cuproptosis and cell wall digestion. Further, the researchers developed a gelatin-DOPA-knob/fibrinogen hydrogel to achieve rapid and robust hemostatic sealing, utilized a double-network polyelectrolyte-coated hydrogel for enhancing endothelialization of left atrial appendage (LAA) occluders, and the researchers also demonstrated that image-guided high-intensity focused ultrasound enables manipulation of shape-memory polymers. Finally, in the realm of photo-electro-magnetic functional polymers, precise control of through-space conjugation was shown to enhance organic luminescence. Topologically structured hydrogels were revealed to exhibit autonomous actuation. Also, solar-driven photothermal ion pumps were developed for selective lithium extraction from seawater, and high-performance non-solvated C60 single-crystal films were prepared via facile bar coating. Lastly, the researchers demonstrated outstanding dielectric properties of polyethylene (PE) lamellar single crystals. The relevant works are reviewed in this paper.
Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction (HER). Here, we reported PtNi nanoparticles with a refined size of 2.71 nm and regular strains loaded on carbon black, synthesized using the high-temperature liquid shock (HTLS) method. This approach offers significant advantages over conventional synthesis methods, including high scalability, rapid reaction rates, and precise control over the size and shape of nanocrystals. Importantly, the synthesized PtNi electrocatalysts demonstrate outstanding catalytic activity and long-term stability for HER, achieving low overpotentials of 19 and 203 mV at current densities of 10 and 1000 mA/cm2, respectively. The superior performance can be attributed to the combination of a refined particle size, lattice strains, and synergistic effects between Pt and Ni. This rapid liquid-state synthesis demonstrated here holds great potential for scalable and industrial manufacturing of micro-/nano-catalysts.
Chiral amino acids (AAs) serve as essential building blocks of proteins and play vital physiological roles in living organisms. To achieve accurate, rapid, and high-throughput analysis of chiral AAs, this work proposed a methylbenzyl isocyanate (MBIC) derivatization strategy coupled with ultra-high performance liquid chromatography-mass spectrometry or trapped ion mobility spectrometry-mass spectrometry. The integration of a chiral carbon atom with a rigid urea-based structure can significantly enhance the separation of chiral MBIC-labeled AA enantiomers. This phenomenon can be attributed to the labeled l-AAs allow the carboxyl group to form intramolecular hydrogen bonds with the amino group in the rigid urea-based structure, whereas labeled d-AAs are unable to form such bonds. The method based on MBIC derivatization coupled with ultra-performance liquid chromatography-tandem mass spectrometry achieved simultaneous separation of 19 pairs of chiral AAs using only a C18 column within 30 min, enabling quantitatively detect twelve types of chiral AAs in the serum of healthy humans and Parkinson's patients. The distribution of twenty-four chiral AAs is observed in mouse brain using MBIC labeling-based matrix-assisted laser desorption/ionization-trapped ion mobility spectrometry-mass spectrometry imaging without prior separation. Our work elucidates the principles governing the separation of chiral AAs using derivatization methods, providing valuable guidance for the separation of chiral compounds.