Organic nonlinear optical (NLO) materials offer excellent opportunities for high-density integration of flexible photonics and optoelectronics that are relevant to communication and computing technologies. Most organic NLO materials nowadays rely on permanent dipole moments in NLO molecules, which require complicated asymmetric molecular structures, bonding schemes, and alignment procedures. Here, we report on the observation of efficient second-harmonic generation (SHG) from a supramolecular nanostructure self-assembled from a basic chromophore. Using polarization-dependent SHG measurements in combination with transient absorption spectroscopy and Monte Carlo simulations, we identify the origin of the SHG to be light-induced transient dipole moments associated with charge-transfer states in the nanostructures. These findings highlight opportunities to harness NLO responses across a broad class of organic molecular assemblies by exploiting light-induced transient effects.

The growing demand for metal-air batteries and fuel cells has spurred extensive research into low-cost, highly efficient, noble-metal-free electrocatalysts to overcome the sluggish oxygen reduction reaction (ORR) at the cathode. Herein, we propose a chemical assembly strategy to engineer an asymmetrically structured Fe-N4 single-atom active site densely embedded within a hierarchical micro-nanoporous aerogel. The asymmetric Fe-N4 single-atom moiety, modulated by N and Cl codopants, enhances intrinsic ORR activity, while the porous aerogel geometry facilitates rapid electron and mass transport. As a result, the resulting catalyst demonstrates high ORR performance, achieving half-wave potentials of 0.92 V in alkaline media and 0.82 V in acidic media, in stark contrast to conventional Fe catalysts with planar coordination symmetries. When used in the H2-O2 fuel cell, a peak power density of 755 mW cm-2 is achieved. Furthermore, Zn-air batteries utilizing this catalyst deliver high peak power densities of 395 mW cm-2 and 161 mW cm-2 for liquid- and solid-state batteries, respectively, while maintaining excellent stability under repeated cycles and various mechanical deformations. Complementing these experimental results, we introduced an explainable XGBoost machine-learning model to accurately predict battery power density, uncovering critical performance trends driven by voltage, catalyst atomistic architecture, and device configurations. This work not only presents a method for fabricating high-performance single-atom aerogel catalysts but also offers valuable design principles for advancing the commercial viability of electrocatalysis-based energy systems.

Artificial photosynthesis through proton reduction or CO2 reduction to generate chemical fuels has gained increasing attention as an attractive strategy for solar-to-fuel conversion. In these systems, the oxygen evolution reaction (OER) provides the necessary electrons and protons for driving the overall reaction but represents the rate-limiting step due to its inherently sluggish kinetics. Therefore, efficient overall artificial photosynthesis requires photocatalysts that can drive both the oxidation and reduction half-reactions, which impose stringent demands on catalyst design. Covalent organic frameworks (COFs) offer a versatile platform for designing such photocatalysts, owing to their strong light-harvesting capabilities , periodic architectures, and highly tunable frameworks that allow programmable catalytic sites and adjustable electronic band structures. While notable progress has been made in developing COF photocatalysts for the OER and overall artificial photosynthesis, these advances remain scattered across the literature and existing reviews, and a dedicated, systematic overview of the OER and its central role in integrated artificial photosynthetic processes is still lacking. This Review systematically summarizes recent advances in COF-based photocatalysts for the OER half-reaction and overall artificial photosynthesis. Our aim is to offer a comprehensive roadmap that establishes fundamental design principles for next-generation COF-based photocatalysts toward efficient and sustainable artificial photosynthesis.

Chirality enlightens promising antitumor strategies. However, the limited understanding of chirality-associated cellular metabolism regulation and cell death mechanisms impede the rational design of chirality-dependent functional nanoplatforms for safe and effective antitumor therapy. In this work, we engineered a propargylamine-linked chiral covalent organic framework (CCOF) and conducted a comprehensive examination of its interactions with living organisms and its cytotoxicity. Our findings demonstrate that CCOF enters tumor cells in a chirality-dependent manner, induces mitochondrial autophagy, and thereby promotes cell death. Furthermore, the efficiency of autophagy activation is influenced by chirality, with (S)-DTzP-COF being more potent than (R)-DTzP-COF. Subsequent high-throughput transcriptomics analysis unveiled the mechanisms underlying CCOF's efficacy against tumors. Additionally, CCOF demonstrates enantiomer-dependent performance in the photocatalytic oxidation of oxygen under laser irradiation, both in vitro and in vivo. Under laser irradiation, the proposed CCOF nanoplatform achieves the desired antitumor effect in three different subcutaneous tumor models. This study represents an application of CCOFs in oncology, uncovering a chirality-dependent mechanism of mitochondrial autophagy induction, with (S)-DTzP-COF engaging the Notch signaling pathway in addition to both (R)-DTzP-COF and (S)-DTzP-COF being involved in the Mitogen-Activated Protein Kinase (MAPK) signaling pathway. These discoveries lay a robust foundation for the advancement of chiral nanomaterials in biomedical application.

Purely organic room-temperature phosphorescence (RTP) is easily quenched by water and oxygen in aqueous systems, severely restricting its application in bioimaging. As two main strategies for achieving aqueous RTP, nanocrystallization and supramolecular self-assembly are not applicable to chromophores that lack crystal luminescence and matrix compatibility. Here, we provide an optional strategy, endogenous oxygen depletion-based emulsion polymerization nanospheres (NSs), for achieving aqueous RTP for the aforementioned chromophores. The aqueous RTP probe is constructed by encapsulating chromophores with high reactive oxygen species (ROS) generation capabilities into poly(methyl methacrylate) (PMMA) NSs prepared via emulsion polymerization. The dense and hydrophobic structure of PMMA NSs, combined with the high ROS generation efficiency of the incorporated chromophores, effectively suppresses phosphorescence quenching by water and oxygen, thereby enabling visible aqueous RTP in an air-exposed environment. In contrast, no RTP is observed in nanocrystalline and supramolecular systems with the same chromophores. The applications of these PMMA NSs in subcutaneous, tumor, and lymphatic tissue bioimaging are successfully demonstrated, with the signal-to-background ratio reaching as high as 556. This strategy is expected to provide a feasible route for developing aqueous-phase RTP nanoprobes and to advance the broader application of organic RTP probes in bioimaging.

Photoacoustic (PA) imaging combines the molecular specificity of optical absorption with the resolution and depth of ultrasound, enabling noninvasive molecular imaging in vivo. However, robust and accurate PA multiplexing is hindered by the broad spectra and poor photostability of existing contrast agents, and interference from endogenous absorbers. Here, we demonstrate four-channel PA multiplexing using PEGylated silica-coated gold nanorods with narrow, spectrally distinct plasmon resonances spanning the near-infrared window. A reproducible three-step seed-mediated synthesis yields monodisperse, spectrally tunable gold nanorods. Co-hybrid silica encapsulation with PEGylation enhances photostability and standardizes both particle dimensions and surface chemistries across the panel. With only a commercial OPO laser and a straightforward non-negative least-squares algorithm, we achieve accurate signal separation across a full-factorial set of in vitro and in vivo models, maintaining mean absolute errors below 4.3%. We further show that the nanorod library remains clearly distinguishable in the presence of endogenous oxyhemoglobin and deoxyhemoglobin and can be unmixed using VisualSonics native spectral deconvolution. This platform doubles existing PA multiplexing capabilities to four exogenous channels without requiring multimodal imaging, complex laser setups, or complicated computational pipelines. This work establishes a framework for future applications in noninvasive biomarker mapping, multicellular therapies, and spatially resolved diagnostics.

Carborane-ligand-protected metal clusters have garnered significant attention due to their exceptional stability, unique electronic properties, and well-defined atomic structures. However, their widespread catalytic applications are often hindered by the shielding of active sites by the bulky carborane ligands. Herin, we developed a mixed-ligand strategy by coassembling strong carboranylthiolate ligands with weak phosphine ligands. Carboranylthiolate ligands play a role in protecting the metal core, while phosphine ligands can easily fall off and expose the metal active sites. This dynamic ligand tuning enabled superior performance in the electrocatalytic nitrate reduction reaction (NO3RR). The optimal Faradaic efficiency (FE) of the Ag3Cu2 cluster was 92.3 ± 0.5%, and the total FE was 99.2 ± 0.8% (NO3- → NO2-/NH3). The dual-ligand system demonstrates a paradigm for balancing stability and activity in nanocatalysts. Beyond NO3RR, this strategy offers a versatile approach to activate other carborane-protected clusters for diverse catalytic transformations, providing a generalizable framework for designing high-performance catalysts with precisely tunable active sites.

Carbon fiber-based electrocatalysts offer significant advantages over conventional powder catalysts, including enhanced active site exposure, superior conductivity, faster reaction rates, lower costs, and improved stability under harsh conditions. In this study, we introduce a rapid and scalable method for spinning carbon-supported metal catalysts into their fibrous forms to achieve uniform catalyst structures that enable roll-to-roll manufacturing. We demonstrate uniform ruthenium (Ru) nanoparticle-loaded carbon fibers by spinning polyacrylonitrile (PAN)-Ru phenanthroline complexes and annealing at 1200 °C for the optimum Ru particle size distribution. We found that the interaction of the Ru complex with the nitrile (-C≡N) group of PAN enabled rheological control and ensured monodisperse Ru confinement. Our investigation of the mechanism details the microstructural evolution during carbonization and oxygen plasma treatment, showing exceptional enhancement in the performance of Ru-embedded carbon fabric electrocatalysts. Ultimately, our rheology-driven spinning protocol bridges the gap between laboratory-scale synthesis and industrial manufacturing of fabric electrocatalysts, providing a versatile platform for nanoconfinement that offers critical insights into the structural evolution of metal-polymer nanocomposites for next-generation energy applications.

Conventional perovskite microcrystals commonly exhibit luminescence thermal quenching and functional singularity, severely limiting their practical utility. The inherent toxicity and instability of lead-based variants further restrict their biomedical applicability. To address these challenges, we synthesized ultrasmall (∼2.5 nm) lead-free Cs2NaGdCl6:Yb3+,Er3+ double perovskite quantum dots (QDs) through an optimized variable-temperature hot-injection approach. These QDs display an anomalous thermal enhancement in upconversion luminescence, attributed to temperature-dependent desorption of surface -OH groups, which enables highly sensitive optical nanothermometry. Simultaneously, they exhibit efficient broadband self-trapped exciton emission under UV excitation. Following surface modification with 2-aminoethylphosphonic acid (AEP), the QDs acquire good hydrophilicity and biocompatibility. Moreover, the Gd3+-rich composition confers outstanding T1-weighted magnetic resonance imaging (MRI) capability with a high relaxivity of 8.23 mM-1s-1. The successful demonstration of in vivo tumor imaging confirms their potential as effective MRI contrast agents. This study establishes ultrasmall lead-free double perovskite QDs as a versatile multifunctional platform integrating nanothermometry and bioimaging functionalities.

Harnessing deoxyribonucleases (DNases) for biodegrading antibiotic resistance genes (ARGs) provides an eco-compatible approach to control antimicrobial resistance; however, translation to high-efficiency removal is hindered by limited access to ARGs and receptor-gated enzyme secretion. Herein, a nano-zoo composite was established for ARG remediation using nanoscale zerovalent iron (nZVI) and worms (Tubifex tubifex). The optimized composite removed extracellular ARGs from 108 to 102 copies/L (99.9999% efficiency) within 72 h in laboratory microcosms and wastewaters, significantly suppressing horizontal gene transfer. Mechanistically, oxidative phase transformation of nZVI enhances inner-sphere Fe-O-P bonding to the DNA phosphate backbone, concentrating ARGs at the interface and promoting fragmentation. Transcript and protein assays demonstrate that ARG fragments activate Toll-like receptor signaling, thereby triggering a 5.71-fold increase in DNase II exocytosis. These findings support a hybrid nano-bio remediation strategy that couples interfacial capture with endogenous nuclease action, providing a scalable route to control emerging genetic pollutants in aquatic systems.