ACS Materials Letters最新文献

At present, numerous microorganisms with high biosafety have been found and used to treat various human diseases. Among them, microalgae are abundant in nature and have simple construction. Moreover, living microalgae possess an inherent capability as a natural oxygenator through photosynthesis, offering superior O₂-producing efficiency and light-controlled performance. Meanwhile, microalgae contain luxuriant active substances, such as carotenoids, chlorophyll, proteins, and fatty acids, that provide specific biological effects in medical applications. Additionally, these microalgae can be further modified or used together with multifarious materials to improve their biocompatibility and biological function, realizing perfect oxygen supply, free radical scavenging, anti-inflammation, and immunomodulatory effects via topical, oral, or intravenous administration. This Review summarizes the research progress and specific applications of microalgae-containing biomaterials in cancer therapy, skin wound healing, gastrointestinal disease treatment, and other human diseases, providing a theoretical basis for the availability of microalgae-containing biomaterials for biomedical applications.

Electroconductive hydrogels offer a unique combination of conductivity and biocompatibility, mimicking the extracellular matrix for bioelectronic applications. Herein, we present a homogeneous, conductive, and cytocompatible hydrogel-based organic electrochemical transistor (OECT) composite, combining methacrylated gelatin (GelMA), PEDOT:PSS, and tetramethacrylated PEDOT:TOS (PEDOT-TMA:TOS). This three-component hydrogel overcomes challenges in PEDOT aggregation, low conductivity, and cytotoxicity. The hydrogel exhibited remarkable electrochemical performance with a five-order impedance reduction, sheet resistance of 1.53 kΩ sq^–1, and conductivity of 2.9 S m^–1. OECTs fabricated with the hydrogel showed a threshold voltage of 0.216 V, transconductance of 2.1 mS, and an on/off ratio of 156.7. Live/dead assays confirmed excellent cytocompatibility due to efficient radical scavenging during cross-linking. This 3D conductive hydrogel network, compatible with cellular integration, establishes a foundation for next-generation bioelectronics, including sensors, neural interfaces, and tissue engineering.

Due to its ultralow magnetic damping, yttrium iron garnet (YIG) film is widely employed in spintronic devices, especially for spin current generation. However, experimental studies have consistently revealed the formation of a thin, poorly crystallized yttrium-rich layer on the top surface of fabricated YIG films, which can significantly impede spin transparency. To address this issue, we propose using an ultrathin amorphous Fe₂O₃ layer grown directly on the YIG film at room temperature as a sacrificial layer, to compensate for the Fe deficiency in the YIG film that occurs during the high-temperature annealing process. The feasibility of this approach has been demonstrated through comprehensive structural, chemical, and magnet-transport studies. In contrast to previously reported post-treatment methods such as ion beam etching or wet acid solution etching, our approach is etching-free and thus offers significantly better compatibility.

Anthropogenic per- and polyfluoroalkyl substances (PFAS), valued for their chemical stability, are widely used in industrial and consumer products. Their persistence leads to bioaccumulation, particularly in water, posing significant risks to human health via contaminated water, food, and PFAS-treated products. Although regulations exist, gold standard analysis is time-consuming, complex, and costly, limiting real-time and in situ monitoring. Efficient, field-deployable detection technologies are urgently needed. This review reports an up-to-date and critical assessment of fluorescence-based sensors, often harnessing engineered nanomaterials, for the detection of PFAS in water with a view to portable systems for in situ monitoring. We discuss the photophysical and chemical principles of these sensors and evaluate key performance metrics─including sensitivity, selectivity, response time, and sample preparation─that affect operational efficiency and field portability. Despite challenges such as matrix interference and sensitivity limits, emerging nanomaterial designs and sensor architectures offer promise for robust, practical continuous in situ PFAS monitoring.

Two-dimensional (2D) magnetic materials show promise for spintronic applications but are hindered by low Curie temperatures (T_c). This study systematically investigates the Fe₃XY₂ material family (X = Ga, Ge, As; Y = Te, I), a rare class of 2D magnets that has demonstrated room-temperature ferromagnetism in experiments. First-principles calculations reveal that the interlayer interaction is closely correlated with the hybridization between the Fe-d orbitals and X-p orbitals. Reducing the number of valence electrons at the X site enhances intralayer ferromagnetic (FM) interactions, which serve as the dominant factor in achieving stronger magnetic ordering and higher T_c. Additionally, the chemical composition at the X/Y site significantly alters the direction of magnetic anisotropy by modulating the electronic band structure along the K–H high-symmetry path. Based on these mechanisms, two high-T_c 2D ferromagnets, Fe₃ZnTe₂ and Fe₃ZnI₂, have been successfully predicted, with an estimated T_c of 390 and 560 K, respectively.

The critical need for better sorbents for CO₂ capture and separation (CCS) is at the forefront of the current research scenario, which is addressed here by synthesizing allomelanin-inspired porous organic polymers (POPs) LPOP-n (n = 1–5). An investigation into the effect of different linkers on CO₂ adsorption revealed an interesting performance trend, with LPOP-2 showing the highest CO₂ uptake, 3.50 and 3.02 mmol/g at 273 and 298 K, respectively, with impressive CO₂/N₂ selectivity. Moreover, a dynamic breakthrough experiment revealed a longer breakthrough time for CO₂ than that for N₂, verifying the feasibility of LPOP-2 for its practical application in the CCS process. Density functional theory (DFT) calculations indicated that noncovalent interactions (NCIs), like π-quadrupole interaction and H-bonding, were crucial in dictating the varying CO₂ adsorption behaviors across the LPOP-n series. This work underscores how simple materials originating from biologically active units can produce biocompatible materials for gas adsorption and separation applications.

Two-dimensional (2D) metal halide perovskite-like quantum wells can be obtained by slicing the inorganic perovskite lattices with large organic molecules, where the number of consecutive inorganic slabs (n) determines the quantum confinement. Synthesizing large-area and ultrathin 2D perovskite sheets is crucial to achieving heterostructures for future thin-sheet optoelectronic devices. In this work, we demonstrate a synthesis method in which perovskite precursor solutions are introduced on an antisolvent liquid surface. Well-defined n = 1 sheets with sub-10 nm thickness and up to 50 μm lateral size are obtained in a scalable manner. This is achieved through careful engineering of subphase and spreading phase compositions to encourage controlled perovskite crystallization at the antisolvent–air interface. Structural and spectroscopic characterizations reveal a high phase purity and a clean excitonic emission, with their overall optical properties comparable to those of the highly crystalline films fabricated by blade coating, highlighting the clear potential of this liquid surface synthesis strategy.

Highly sp²-hybridized disordered carbons stand out because of their versatile and often complex extended-range order, characterized by curved layers with rings of varying sizes, stacking disorder, and other defects. Understanding this extended-range order is crucial for grasping its role in numerous applications. In this study, we demonstrate the use of the pair-angle distribution function (PADF) analysis to address this challenging task. The three-dimensional aspect of the PADF enables the extraction of a wide range of information, including the ability to separately study intra- and interlayer disorder─a difficult task with other methods like one-dimensional pair distribution functions. Using PADF analysis thus improves our understanding of the extended-range order, which is essential for customizing carbons for specific applications. The proof-of-concept demonstration of separating inter- and intraplane disorder in layered materials also introduces a powerful new approach for studying other materials, including MXenes and layered double hydroxides.

To date, the pressure-dependent luminescence behavior of purely organic compounds represents a significant research interest within the realm of stimulus-responsive smart materials. Most previous studies have predominantly focused on fluorescence properties, while investigations into the pressure-regulated room-temperature phosphorescence (RTP) remain relatively underexplored. This work innovatively proposes a strategy to achieve pressure-induced RTP enhancement through the introduction of aromatic carbonyl and intramolecular interactions. The donor–acceptor structure and ortho-substituted position enables BP-o-DMAC to adopt a twisted V-shaped conformation with intramolecular C–H···O hydrogen bonds and a charge transfer feature. Upon compression, the intramolecular C–H···O interaction is enhanced by pressure, which effectively suppresses nonradiative energy loss, promotes spin–orbit coupling, and stabilizes triplet excitons, consequently boosting RTP efficiency within the pressure range. Comparative experiments further confirm the crucial role of intramolecular interactions in achieving RTP enhancement. This work provides a new approach for designing piezochromic materials, especially with pressure-induced RTP enhancement.

Water management, nutrient use efficiency, and pathogen prevention are the major parameters that are critical to optimize crop yields. Alternate approaches to manage these parameters are of the utmost importance. A dual-functionality biodegradable hydrogel with an inherent biocidal property and multinutrient delivery could be of potential interest. Nitrate-loaded carboxymethylcellulose–zinc–cobalt (CMC-Zn-Co) cross-linked hydrogel beads showed excellent swelling/deswelling behavior and were effective against two major plant pathogens, Xanthomonas citri. pv. citri and Ralstonia solanacearum, which cause wilt disease in plants. The hydrogel matrix facilitates the slow release of nitrate and eventual discharge of Zn and Co upon degradation. Density functional theory (DFT) studies reveal the interaction of Zn²⁺ and Co²⁺ ions with the CMC upon bead formation. Environmentally benign CMC-Zn-Co cross-linked hydrogel beads could be a one-stop solution for multinutrient fertilization, water management/soil conditioning, and pathogen prevention that would limit the administration of multiple agents, lowering production cost and boosting environmental sustainability.