Nano Letters最新文献

Molecular logic gate circuits show promise for decoding multibiomarker patterns in diagnostics, but achieving precise logic control and high-fidelity amplification remains challenging. Here, we develop a logic-gate-controlled positive-feedback DNAzyme circuit for one-pot detection of dual miRNA (termed DECODER). DECODER utilizes an engineered dual-catalytic-core 8–17 DNAzyme as the logic switch. Each core is specifically activated by a target miRNA to cleave one of the two rA sites on a designed probe. Fluorescence is emitted only upon dual cleavage, enabling the AND logic operation. The cleavage generates new 3′ ends that act as primers to initiate two independent RCA reactions. The programmed RCA products hybridize to form E6 DNAzymes, which cleave more probes and establish a self-sustaining positive-feedback loop, amplifying the initial AND logic signal with high fidelity. DECODER achieves a detection limit of 79.8 fM within 75 min. In serum tests, it diagnosed early stage nonsmall cell lung cancer with 88.3% accuracy, demonstrating strong translational potential.

Hydrogenation in redox-active oxides is widely used to modulate electronic structure and, in turn, optical, magnetic, and transport properties in electrochromic, energy-storage, and ionotronic devices. Quantitatively resolving hydrogenation is therefore critical for rational device design. However, a general operando framework that directly quantifies potential-dependent proton concentration while decoupling ionic and electronic transport and linking both to defect thermodynamics remains limited. Herein, using La_0.6Sr_0.4FeO_3-δ thin films as a model system, we develop an integrated methodology that combines operando spectro-electrochemistry, electrochemical impedance spectroscopy, and defect-chemistry analysis to interrogate hydrogenation across applied potentials. The operando spectro-electrochemical signal, calibrated by coulometric titration, maps absorbance changes to proton concentration, enabling direct determination of its potential dependence. Impedance spectroscopy separates ionic and electronic contributions, yielding potential-dependent chemical capacitance and ionic conductivity. Defect-chemistry analysis further supports the reliability of the observed potential-dependent trends. We believe this approach is readily transferable to other redox-active oxides.

Organic electrode materials represent promising candidates for aqueous zinc-ion batteries (AZIBs) due to their structural tunability, sustainability, and cost-effectiveness. However, their practical application is impeded by sluggish ion transport, dissolution, and limited reversible capacity. Herein, an ultralight aerogel (F-COF@rGO) was constructed through the self-assembly of fluorine-rich covalent organic framework nanospheres and reduced graphene oxide into a three-dimensional hierarchical porous network. The incorporation of highly electronegative fluorine atoms enhances Zn²⁺ affinity, promotes electron delocalization, and improves conductivity, collectively facilitating Zn²⁺/H⁺ cointercalation and stabilizing reversible redox transitions. As a result, F-COF@rGO delivers a high reversible capacity, excellent rate capability, and outstanding long-term durability. In situ/ex situ characterizations and density functional theory calculations reveal that Zn²⁺/H⁺ costorage can be attributed to the synergistic porous architecture and fluorine-ligand-induced selective ion migration. This work establishes a molecularly engineered composite strategy for a fluorinated COF-based aerogel, advancing sustainable, high-performance organic electrodes for next-generation aqueous energy storage.

Controlling the collective optical properties of chiral plasmonic systems is essential for advancing photonic and chiral sensing technologies. Using template-assisted self-assembly, we engineered one-dimensional chiral plasmonic linear arrays composed of highly anisotropic chiral gold nanoparticle chains in an end-to-end configuration, achieving tunable plasmonic and chiroptical properties. While isolated chiral NPs exhibit intrinsic plasmonic circular dichroism (CD), their periodic arrangement introduces surface lattice resonances, yielding sharp extrinsic CD peaks. Orientation- and angle-dependent CD measurements enable a clear differentiation between intrinsic and extrinsic CD contributions. Notably, at specific angles of incidence, the assembled arrays exhibit a significant enhancement in the chiroptical response, demonstrating the dynamic tunability of their optical activity. The chiroptical properties of the arrays can be transferred to a luminescent dye, thereby yielding circularly polarized emission. These chiral superlattices supporting intrinsic and extrinsic chiroptical properties offer a robust platform for photonic devices, ultrasensitive chiral sensing, and enantioselective applications.

Si-based all-solid-state batteries are promising candidates for achieving high-energy density but are hampered by sluggish kinetics and deleterious stress accumulation at the rigid solid–solid interfaces within Si anodes. Herein, we report a mechanically and conductively adaptive interface that transforms the rigid solid–solid interfaces in Si anodes into soft, highly conductive ones through its deformation capability during cycling, enabling high-rate and long-cycle-life batteries. The interfacial phase in the lithiated state exhibits a lower Young’s modulus and higher mixed-conductivity than Si and its alloys, facilitating a uniform and low-stress field within the Si electrode that effectively stabilizes the interfacial transport. Upon delithiation, it spontaneously heals stress-induced interfacial damage, preserving a robust three-dimensional adaptive network throughout cycling. The dynamically adaptive interface enables a pouch cell to cycle stably over 150 cycles at 1C, with 94% capacity retention. Our work provides valuable insights into the stability of solid–solid interfaces that are crucial in practical all-solid-state-batteries.

High-quality perovskite films are essential for achieving efficient and stable perovskite solar cells (PSCs), requiring precise control over the precursor chemistry, crystallization kinetics, and defect passivation. However, achieving the simultaneous regulation of these coupled factors through a single strategy remains challenging. Here, we introduce sodium hydroxymethanesulfonate (SHMS) as a multifunctional additive to the perovskite precursor to enable a precursor-to-film regulation effect. In the precursor, this multifunctional additive suppresses cation side reactions via electrostatic attraction and hydrogen bonding, while inhibiting the formation of triiodide (I₃^–); in the film, it modulates crystallization kinetics through coordination interactions forming an intermediate complex with PbI₂ and passivates defects to enhance film quality and stability. The resulting inverted PSCs incorporating SHMS achieve a power conversion efficiency of 26.10% (certified value of 25.66%) with a fill factor of 87%, together with excellent thermal, moisture, and light stability. Moreover, when integrated into a solar-charged supercapacitor, the device delivers an overall energy conversion efficiency of 11.84% with an outstanding cycling stability.

Single-atom sites (SASs) and their electrocatalysts offer outstanding catalytic activity and metal efficiency. Metal–organic frameworks (MOFs), with their tunable and multifunctional architectures, serve as ideal precursors for SASs, enabling atomic-level dispersion. However, current research often overlooks critical ambiguities in SAS definitions, intrinsic limitations, and characterization reliability. Moreover, prevalent destructive treatments, such as pyrolysis or sulfidation, inevitably compromise framework integrity, raising concerns regarding the trade-off between structural designability and conductivity. Accordingly, this Mini-Review critically revisits MOF-derived SASs by scrutinizing synthesis limitations and emphasizing the quantitative assessment of atomic utilization efficiency. Representative examples of emerging framework-retaining strategies, including ligand and defect engineering, are discussed to illustrate opportunities for preserving MOF advantages. Finally, future directions are proposed, focusing on dynamic structural reconstruction and operando validation to simultaneously enhance activity, stability, and scalability for practical energy conversion applications.

We propose and theoretically demonstrate nonreciprocal negative refraction enabled by time-varying photonic structures. By engineering temporal modulations at the interfaces of hyperbolic media, we achieve isolation between forward and backward beams while preserving the hallmark property of negative refraction. Two complementary approaches are developed: in the optical regime, a multilayer AZO/ZnO hyperbolic slab is sandwiched between permittivity-modulated dielectric layers (3D time crystals); in the microwave regime, a wire medium is sandwiched between time-modulated resistive metasurfaces (2D time crystals). Both designs exploit Floquet harmonic expansions and are validated with a customized harmonic-balance finite-element solver. We report isolation exceeding 46 dB in the optical device and 11 dB in the microwave counterpart. This work introduces a general framework for nonreciprocal negative refraction across frequency regimes, expanding the design space of time-varying metasurfaces and photonic time crystals.

Curvilinear magnetic nanostructures enable control of magnetization dynamics through geometry-induced anisotropy and chiral interactions, as well as magnetic field modulation. In this work, we report a curvilinear magnonic crystal based on large-area square arrays of truncated nanospikes fabricated by conformal coating of 3D hierarchical templates with permalloy thin films. Brillouin light scattering spectroscopy reveals an anisotropic band structure with multiple dispersive and folded Bloch-type dispersive spin-wave modes as well as nondispersive modes exhibiting direction-dependent frequency shifts and intensity asymmetries along lattice principal axes. Finite element micromagnetic simulations indicate that curvature-induced variations of the demagnetizing field govern the magnonic response, enabling the identification of modes propagating in nanochannels and others localized on nanospike apexes or along the ridges connecting adjacent nanospikes. The combination of geometric curvature and optical probing asymmetry produces directional dependence of magnonic bands, establishing 3D hierarchical templates as a versatile platform for curvature-engineered magnonics.