Materials Chemistry Frontiers最新文献

Lymphatic system diseases, such as lymphoma and lymphedema, present significant diagnostic and therapeutic challenges due to the complex structure of the system and the risk of damaging healthy tissues by using conventional treatments. In recent years, inorganic nanomaterials (INMs) have emerged as powerful theranostic agents due to their tunable sizes, unique optical/magnetic properties, and facile surface functionalization. This review comprehensively summarizes the latest advancements in leveraging a range of INMs, using techniques including X-ray and photoacoustic imaging, high-resolution fluorescence tracking, and controlled drug delivery in the management of lymphatic diseases. We elaborate on their roles not only as contrast agents for precise anatomical and functional imaging of lymphatic vessels and nodes but also as targeted therapeutic platforms for photothermal therapy, and combination treatments. A significant portion is dedicated to the design and application of all-in-one nanoplatforms that integrate real-time diagnostic monitoring with spatially controlled therapeutic intervention, thereby achieving true “visualized therapy.” The significance of this work lies in articulating how these nano-engineered strategies can overcome biological barriers, enable high-precision theranostics, and potentially revolutionize patient outcomes. Finally, we discuss the current challenges regarding long-term biocompatibility and clinical translation and provide an outlook on the future integration of INMs with emerging technologies for personalized medicine.

By the combination of chemical liquid-phase reduction, in situ self-oxidation and thermal treatment, tri-layer Co@Co_xFe_1−x@Fe@Fe₃O₄ thorny core–shell composite magnetic particles were synthesized, and their microstructure, static magnetic properties, and electromagnetic wave absorption performance were investigated. Results show that the tri-layer Co@Co_xF_1−x@Fe@Fe₃O₄ thorny particles largely retained the morphology of thorny Co@Fe@Fe₃O₄ particles, but some particles are aggregated, resulting in an increase in the particle size. The tri-layer Co@Co_xF_1−x@Fe@Fe₃O₄ thorny particles exhibit a typical core–shell structure with an internal core and 200–300 nm thick external coating. The center of the particle contains Co, while the outer layer comprises Fe and O. With heat treatment, a discernible transition phase of CoFe and Co₇Fe₃ was formed at the Co/Fe interface. With the increase in self-oxidation temperature, the specific saturation magnetization of the Co@Co_xF_1−x@Fe@Fe₃O₄ particles exhibits a slight increase before a downward trend, while the coercivity decreases slightly and then increases. At an oxidation temperature of 70 °C, the tri-layer Co@Co_xFe_1−x@Fe@Fe₃O₄ thorny particle samples exhibit optimal absorption performance, with a minimum reflection loss of −24.42 dB at a coating thickness of 1.6 mm and a maximum effective absorption bandwidth of 4.80 GHz.

Martensitic single-crystal-to-single-crystal phase transitions, being rare in organic crystals, can result in several phenomena with promising potential applications, including thermosalient effect, shape memory and self-healing. We report here the first charge-transfer cocrystal of 9,10-dimethylanthracene and 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane, exhibiting a unique combination of dynamic properties stemming from a martensitic phase transition. This organic material demonstrates thermosalient and self-healing behavior, alongside shape recovery during heating and cooling cycles. These effects are driven by collective rotational and translational movements of rigid molecular frameworks, resulting in significant structural changes, while maintaining the process reversibility. Raman spectroscopy, combined with DFT calculations and electron density distribution analysis, provides insight into intermolecular interactions and the potential mechanism of the phase transition. Concurrently, the system displays characteristics of a narrow-gap semiconductor based on transport properties.

Quantum dot light-emitting diodes (QLEDs) are promising optoelectronic devices for next-generation display applications. Poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS) has been widely utilized as the hole injection layer (HIL) in QLEDs due to its high conductivity. However, the strong acidity and hydroscopicity of the PSS component cause corrosion of the electrodes, which leads to device instability. Herein, a near-neutral pH PEDOT:PMA powder is synthesized as the HIL using phosphomolybdic acid hydrate (PMA) as an oxidizing agent, which exhibits higher chemical stability, electrical conductivity and work functions than PEDOT:PSS. Benefiting from improved hole mobility and better carrier balance, the state-of-the-art red QLEDs achieve the highest external quantum efficiency (EQE) of 32.24%. In addition, X-ray photoelectron spectroscopy results reveal that the permeation of dissociated indium from ITO to PEDOT:PMA is greatly delayed compared to that at the ITO/PEDOT:PSS interface, thereby enhancing the stability of the device. This work highlights a promising strategy for a stable PEDOT derivative, which could play a pivotal role in advancing high performance QLEDs.

Two-photon absorbing fluorophores have emerged as powerful imaging agents, offering advantages such as high spatial resolution, deep light penetration, minimal photobleaching, minor photodamage, and low autofluorescence. However, existing two-photon absorbing fluorophores still face the limitation of a small two-photon absorption cross-section. The conventional approaches toward fluorophores with a large two-photon absorption cross-section involve enhancing intramolecular charge transfer, extending the π-conjugation length, increasing the number of π-conjugation paths, improving coplanarity, etc. These approaches are promising but hindered by synthesis complexities, large molecular weight (low membrane permeability), poor solubility, low photostability and aggregation-caused quenching. Herein, we summarize an emerging strategy, namely molecular regioisomerism, which could improve the two-photon absorption performance through adjusting molecular symmetries, molecular π-conjugations, molecular orbital distributions, molecular dipoles, and/or intermolecular interactions. This review can guide the design and synthesis of regioisomers of organic chromophores with good two-photon absorption performance, as well as deepen the research on the structure–property relationship of the regioisomers.

Although supported metal nanoparticles (NPs) have demonstrated great potential in heterogeneous catalysis, the regulation of their interaction with the support framework remains a significant challenge. Herein, we employed a pore-wall functionalization strategy to construct four covalent organic frameworks (COFs) with distinct chemical microenvironments. Palladium nanoparticles were incorporated into the frameworks (Pd@TA, Pd@TA-4F, Pd@TA-OCH₃, and Pd@TA-OHex), and the materials were applied in the multicomponent reaction of carbon dioxide. Impressively, modifications in the pore-wall microenvironment exhibited a regular modulating effect on the catalytic performance of the Pd NPs. Among them, Pd@TA-OCH₃, which combines electron-donating effects and low steric hindrance, demonstrated the best catalytic performance. Furthermore, due to the altered surface microenvironment, Pd@TA-OCH₃ exhibited optimal enrichment and adsorption (k = 0.32 h⁻¹) behavior toward the substrates. In-depth catalytic and adsorption experiments, along with DFT calculations, confirmed the structure–activity relationship between the microenvironments of the COFs and their catalytic performance.

Perovskite solar cells (PSCs) have emerged as promising low-cost photovoltaics, combining high efficiency with solution-processable and scalable fabrication. Realizing stable PSCs via ambient-condition processing is critical for practical, large-area manufacturing. Natural additives offer a sustainable means to direct perovskite crystallization and improve film quality; however, the relationship between their molecular structure and perovskite nucleation, defect passivation, and stability—especially under high-humidity conditions—remains underexplored. Here, we systematically investigate the impact of starch structures, focusing on the ratio of linear amylose to branched amylopectin, on perovskite formation at 50% relative humidity. We demonstrate that amylose-rich starch templates the growth of highly oriented, compact perovskite films with significantly suppressed defect densities. This molecular templating enhances the optoelectronic quality of the perovskite absorber, resulting in a 15% improvement in the power conversion efficiency of all-solution-processed carbon-based PSCs. Moreover, devices incorporating amylose exhibit markedly improved operational stability, with suppressed burn-in and a doubled T₈₀ lifetime under ISOS-L-1 testing. These results reveal the crucial role of natural polymer structures in modulating crystallization pathways and defect chemistry under real-world conditions. Our findings establish a design principle for sustainable, ambient condition-processable PSC fabrication and provide a blueprint for eco-friendly additive engineering in hybrid optoelectronic materials.

A series of dicationic pyrazolium hexafluorophosphate (PF₆⁻) salts connected by a butylene bridge were synthesized with side linear alkyl chains ranging from C₁ to C₁₂. Thermal analysis revealed that most compounds exhibit one or more solid–solid phase transitions (T_ss), and several compounds displayed clear characteristics of organic ionic plastic crystals (OIPCs), with entropy of fusion (ΔS_f) values below 40 J mol⁻¹ K⁻¹. Among them, 1,4-bis[N-(N′-octylpyrazolium)]butane PF₆⁻ exhibited the softest plastic crystal morphology, as confirmed by polarized optical microscopy (POM) and wide-angle X-ray scattering (WAXS), and achieved a high ionic conductivity of 1.31 × 10⁻³ S cm⁻¹ at 70 °C upon incorporation of 30 mol% lithium bis(trifluoromethanesulfonyl)imide (LiTf₂N). These findings demonstrate that the structural tunability of dicationic pyrazolium salts plays a key role in modulating solid-state ionic conductivity, providing insights into the design of next-generation electrochemical materials.

Due to its high efficiency and minimally invasive nature, PTT has received widespread attention. However, traditional PTT leads to the generation of excessive reactive oxygen species (ROS) and inflammatory responses, which exacerbates tumor metastasis and limits its therapeutic efficacy. In this study, we synthesized a polyethylene glycol modified iridium nanoparticle (IrNpP) with high photothermal conversion capacity and ROS scavenging activities. The IrNpP effectively inhibits the tumor cell growth and suppresses the tumor tissue growth. More importantly, the IrNpP extensively eliminates ROS, which significantly mitigates the inflammatory response and effectively inhibits tumor metastasis. Besides, the IrNpP exhibits negligible side effects, suggesting its high potential for biomedical applications. This strategy effectively achieves ablation of tumor cells while minimizing the side effects of photothermal therapy, overcoming the shortcomings of PTT in tumor treatment and providing a new avenue for its application.

Hydrogels, with their highly hydrophilic, three-dimensional polymer network structure, offer great potential as antimicrobial biomedical materials. However the overuse of antibiotics has led to drug-resistant bacteria, highlighting the need for multifunctional biomaterials that do not rely on antibiotics to combat infections. In this study, a multifunctional photothermal antimicrobial hydrogel (PHDF hydrogel) was synthesized using a one-pot method from polyvinyl alcohol, borax, dopamine-grafted hyaluronic acid, and ferric chloride. The hydrogel's self-healing properties were achieved through the formation of borate bonds between polyvinyl alcohol and borax, metal–ligand bonds between dopamine and Fe³⁺, and hydrogen bonds between macromolecules, prolonging its action time. The catechol–Fe³⁺ complex demonstrated outstanding photothermal antibacterial performance, achieving approximately 99% antibacterial efficacy against Staphylococcus aureus and Escherichia coli upon exposure to near-infrared light. In addition, the hydrogel has adjustable rheological properties, antioxidant properties, tissue adhesion, injectability and good hemocompatibility and cytocompatibility, making it a promising antimicrobial material.