Electrochromic technology provides an efficient method for photothermal modulation, owing to its tunable optical absorption properties. Solid-state electrolytes provide superior safety for electrochromic devices (ECDs) compared to conventional liquid electrolytes. However, the sluggish ion diffusion in solid-state electrolytes severely impedes the response speed of ECDs. In this work, an inorganic nanofiber-polymer composite-based quasi-solid electrolyte consisting of a silica (SiO2) nanofiber membrane and a poly(methyl methacrylate) (PMMA) polymer electrolyte was designed, which facilitated the rapid transportation of Li+ ions. As a nanofiller with a high aspect ratio, SiO2 nanofibers can reduce the crystallinity of polymers. Meanwhile, the mobility and arrangement of PMMA chains near the nanofiber surfaces were altered, creating an interfacial region that facilitated ion transport. Consequently, Li+ ions can migrate more rapidly along the surfaces of the SiO2 nanofibers or through the interfacial network formed around them. Moreover, the SiO2 nanofiber membrane served as a framework that provided support for the PMMA-based polymer electrolyte. The composite quasi-solid electrolyte exhibited a high ionic conductivity (4.42 mS cm-1 at 20 °C). The composite electrolyte-based ECD employed tungsten trioxide and vanadium pentoxide as electrodes and achieved reversible color changes between transparent light grayish and deep blue. The ECD exhibited a fast switching speed (0.96 s for coloring and 0.8 s for bleaching), a high coloration efficiency (CE = 247.36 cm2 C-1), and an outstanding cycling stability (maintaining 86% performance after 1500 cycles (54 785 s)).

Ordered double transition-metal (DTM) MXenes are a subfamily of two-dimensional (2D) carbides, nitrides, and carbonitrides, predicted to outperform single-metal MXenes in hydrogen evolution reaction (HER) catalysis due to the synergistic effect of two metals and their nonmetal (X) sublattice tailoring (X = C, N), resulting in tunable electronic structures. However, all synthesized DTM MXenes to date contain only carbon in the X sublattice. Here, we report the synthesis of a series of out-of-plane ordered DTM carbonitride MXenes (o-MXenes), Mo2Ti(CN)2Tx and Mo2Ti2(CN)3Tx, to systematically investigate the role of carbon to nitrogen ratio. To determine the optimal nitrogen content, we first evaluated the HER activity of the Mo2TiC2-yNyTx MXenes with density functional theory calculations and identified that 0.3 to 0.6 mol of nitrogen give enhanced performance compared to the carbide. We next synthesized and characterized 11 carbonitride MXenes with varying their C:N ratios and found nitrogen incorporation enhances HER activity compared to their carbide counterparts. Among them, Mo2TiC2-yNyTx MXene with 0.6 mol of nitrogen (y = 0.6) achieved the best performance, with an overpotential of ∼155 mV at 10 mA/cm2 under acidic conditions, compared with ∼236 mV for Mo2TiC2Tx. Our experimental and computational findings indicate that carbonitrides with ∼25-30 atom % nitrogen outperform all other o-MXene counterparts, with the improved performance arising from nitrogen-induced modulation of the electronic structure. This study identifies nonmetal sublattice control as a critical frontier in optimizing MXenes for sustainable energy applications.

Membraneless compartments formed by liquid-liquid phase separation (LLPS) regulate biochemical reactions and play a key role in both physiological and pathological processes, including viral replication. In retroviral systems, the extent of genome folding is critical for the efficient packaging of new viral particles, a process mediated by the nucleocapsid (NC) protein that chaperones RNA folding and assembly. Here, we sought to elucidate how nucleic-acid folding and structural folding influence LLPS and whether an HIV NC-derived peptide (HNP) can modulate this process through chaperone-like activity. To this end, we designed a programmable single-stranded DNA (ssDNA) library spanning varying degrees of folding and palindromic architectures, enabling systematic investigation of how nanoscale structural order governs coacervation. Using circular dichroism, FRET, SAXS, and coarse-grained simulations, we correlate DNA conformations with phase behavior and emergent condensate material properties. We find that interactions with HNP promote DNA folding and that increasing DNA order suppresses LLPS, whereas structural disorder and palindromic linkers that induce DNA dimerization enhance phase separation by facilitating multivalent interactions and in turn increasing condensate viscosity. Together, these findings identify two programmable determinants, local structural order and palindromic dimerization, that govern DNA/peptide condensate behavior, offering mechanistic insight into viral genome organization and guiding principles for tuning the physicochemical and material properties of synthetic condensates.

Understanding chemotaxis at the molecular level is challenging, as individual enzyme molecules cannot sense chemical gradients across their nanometer-sized bodies. Typical theoretical models encompass chemotaxis under constant, externally imposed gradients; however, this overlooks a critical feedback loop, where the active enzymes themselves reshape the imposed gradients through catalysis. In this work, we investigate the principles of active molecular chemotaxis using a Fokker-Planck model for an ATP-driven kinase-phosphatase system. Using experimentally relevant enzyme concentration ranges (∼nM), we demonstrate that the chemotactic velocity of enzymes does not simply respond linearly to chemical gradients, as commonly observed in microscale systems driven by diffusiophoresis. Instead, it emerges from a nonlinear coupling between the enzyme's spatial distribution, its conformational state (free/bound-state ratio), and chemical gradients modulated by catalytic reactions. As a result, the spatial profile of chemotactic velocity transitions between monotonic and nonmonotonic regimes, depending on substrate availability. Furthermore, we find that high catalyst concentrations can amplify the effective interaction between enzymes, forming a cascade that is critical for collective assemblies such as metabolon formation. To understand these complex interactions, we construct chemotactic velocity maps as a function of enzyme concentration, energy, and substrate availability, offering a set of design principles. This work clarifies the distinct roles of energy, gradients, and enzyme free/bound states in molecular motion, highlighting a fundamental difference between nano and microscale systems, and provides a theoretical framework for designing advanced autonomous active molecular systems.

Lasers are essential optical modulation sources because of their narrow line width and high coherence. Two-dimensional transition-metal dichalcogenides (TMDCs) exhibit strong exciton binding energy and high material gain and are promising candidates for use in compact, low-threshold semiconductor lasers. Although their intrinsically short exciton lifetimes imply faster modulation compared with bulk semiconductors, no direct TMDC laser modulator has yet been realized. This paper presents a high-speed, room-temperature direct modulator based on a threshold-gain-tunable monolayer tungsten disulfide (WS2) microdisk laser. In this modulator, gate voltage can be tuned to modulate the intensity of the lasing output through both carrier density variation and threshold gain control, achieving 50% greater modulation depth compared with normal spontaneous emission. Electrical tuning simultaneously affects the carrier density, dielectric environment, and optical confinement between the WS2 monolayer and the cavity. Radiofrequency measurements revealed a 3 dB intensity modulation bandwidth exceeding 120 MHz. Overall, these results demonstrate the feasibility of high-speed direct optical modulation with TMDC lasers, creating opportunities for the development of compact, energy-efficient optoelectronic systems.

Targeting apoptotic pathways holds promise for cancer treatment; however, single-pathway approaches often struggle to overcome apoptosis resistance and metastasis. Overexpression of Inhibitor of Apoptosis Proteins (IAPs), particularly Survivin, is critically linked to these therapeutic challenges. Herein, a multistage-responsive nanoCRISPR (MIRV) system targeting the IAPs member Survivin in the nucleus and mitochondria in the cytoplasm was developed to suppress tumor growth and metastasis via cascade-amplified endogenous apoptosis and epithelial-mesenchymal transition (EMT) inhibition. By leveraging the tumor-specific targeting, enzyme-triggered penetrating and deshelling, and reactive oxygen species (ROS)-responsive capabilities, MIRV precisely delivers the Survivin-targeting CRISPR/Cas9 system and the pro-apoptotic peptide D(KLAKLAK)2 to the nucleus and cytoplasm of tumor cells, respectively. Survivin depletion-triggered endogenous apoptosis and EMT inhibition, cooperating with peptide-induced mitochondrial dysfunction, enabled MIRV to markedly suppress subcutaneous tumor growth and peritoneal metastasis with minimal side effects. Taken together, the MIRV system provides an effective strategy for the simultaneous induction of apoptosis and suppression of EMT in antitumor and antimetastatic therapies.

Photoluminescence (PL) power efficiency, represented by the ratio of emitted to absorbed light energy, is a crucial factor for applications like radiative cooling. Yet, unlike PL quantum yield, achieving near-100% power efficiency in PL emitters remains mostly elusive. Here, we use spectrally resolved absolute radiometry method to study the PL quantum yield and power efficiency of solution-dispersed CsPbBr3 quantum dots (QDs). The samples were optimized by ligand engineering and controlled aging over the span of several months. Absorption edge changes reveal that the aging causes self-healing of intraband defect states that are otherwise contributing to a decrease of the PL quantum yield. In the optimized samples, we observed PL quantum yield reaching 100% and the PL power efficiency also approaching unity. This result means that all the absorbed excitation light energy is reemitted as luminescence. For the excitation wavelength of 532 nm, the emitted light energy comprises ∼ 80% of anti-Stokes PL and 20% of Stokes-shifted PL, while for the wavelength of 543 nm, the emission is composed entirely of anti-Stokes PL. These parameters are promising for many potential advanced applications, such as radiative cooling.

Nerve regeneration after spinal cord injury (SCI) is severely hindered by a hostile microenvironment, where excessive reactive oxygen species (ROS) and uncontrolled inflammation form a vicious cycle, triggering secondary injury cascades. However, most current treatments are single-target strategies, obtaining marginal benefits for the intricate pathological mechanisms after SCI. Herein, we developed a nanozyme-switched efferocytosis initiation platform, termed CM-ApoV, by integrating mesenchymal stem cell-derived apoptotic vesicles (ApoVs) with cerium-melatonin nanozymes (Ce-MT). As a distinct subtype of extracellular vesicles, ApoVs are enriched with functional proteins that mediate immunomodulation. Besides, phosphatidylserine (PtdSer) exposed on the surface of ApoVs serves as a critical "eat me" signal that enables targeted recognition and efferocytosis by microglia, thereby promoting microglial repolarization and modulating their functions. Ce-MT nanozymes were anchored onto ApoVs to enhance their ROS scavenging capacity. In the meanwhile, the reversible attachment and detachment of Ce-MT mask PtdSer during systemic circulation and enable re-exposure of PtdSer in an oxidative microenvironment at the injured site. Consequently, the CM-ApoV system comprehensively remodels the pathological network and establishes a favorable microenvironment for neuronal repair. In a rodent model of SCI, CM-ApoV promoted neuronal survival, modulated microglial function, and reduced glial scar formation, ultimately leading to a significant improvement in motor function. Overall, this system highlights the synergistic therapeutic potential of the nanozyme-ApoV hybrid platform and provides a feasible strategy for multidimensional treatment of SCI.

Although sonodynamic therapy (SDT) has shown promise in reducing atherosclerotic plaque burden, its clinical application remains confined to superficial lesions, as deep-seated plaques such as those in coronary arteries lack precise imaging guidance and lesion-specific energy delivery. Here, we report an intravascular ultrasound (IVUS)-guided SDT strategy that integrates high-resolution imaging and precise treatment within a single catheter system. Osteopontin (OPN)-targeted bismuth-based nanoparticles (BSNPs), endowed with piezoelectricity through defect-induced symmetry breaking, selectively accumulate in foam cells. Pulsed ultrasound emitted by the IVUS catheter triggers BSNPs to generate reactive oxygen species (ROS) through the modulation of pulse-repetition time (PRT) and pulse width (PW), thereby inducing foam cell apoptosis and promoting plaque regression. With IVUS guidance, the SDT process can be visualized in real time, ensuring precise lesion-specific treatment. Systematic in vitro and in vivo studies demonstrate the effective antiatherosclerotic effect with minimal adverse effects. This imaging-integrated piezo-sonodynamic platform establishes a multifunctional catheter-based ultrasound theranostic strategy, providing a precise and clinically translatable approach for treating atherosclerosis.

The effect of preparation conditions on the properties of glassy polymers has been a subject of intense research, and these glassy polymers also age with deleterious consequences on properties. Here, we surprisingly find a similar preparation dependence for polymer-grafted nanoparticle melts (PGNP), even when the chains are in the melt. Specifically, we show that processing PGNPs by spin-casting vs slowly casting them from solutions yields temporally stable states with vastly different properties, including surface morphologies, mechanical properties, and gas transport. We propose that these differences arise because the end-grafted polymer brushes, especially for high grafting density and short chain lengths, are in an extremely long-lived colloidal glassy state, even though the chains themselves are mobile. Simulations suggest that there are strong variations in the chain interpenetration states between adjacent nanoparticles driven by solvent evaporation rates. With slower evaporation, there is evidently increased chain interpenetration leading to mechanical property improvements, while collapsed brushes dramatically increase gas permeability properties under fast evaporated conditions. These results strongly argue that processing protocols are an unappreciated control variable in determining the temporally stable properties of this class of materials.