Materials Horizons最新文献

Controlling liquid metal (LM) wetting in confined microstructures is essential for reliable liquid-state electronics. Here, well-defined sawtooth microchannels are fabricated by soft replication from a metallic master, enabling systematic investigation of the relationship between channel geometry and electrical response. During injection, pressure decay produces graded LM filling within the sawtooth valleys. Upon tilting, gravity induces localized and angle-dependent LM redistribution rather than uncontrolled bulk sliding, thereby modifying the effective conductive pathway and generating an approximately sinusoidal resistance response. The resulting sawtooth LM tilt sensor exhibits a periodic response over a complete 360° rotation, with a monotonic interval from -90° to +90° that enables unique angle determination. Repeated 0.1° angular-step inputs produce distinguishable resistance changes, and the apparent system-level response time remains below 0.4 s under the tested conditions. The device maintains stable responses over 2000 rotation cycles and during intermittent measurements over a 30 day period. Its versatility is demonstrated in engineering attitude monitoring, human-motion sensing, angle-encoded information transmission, and surface-height mapping. This work presents a rational microstructure-design strategy for converting gravity-mediated LM redistribution into stable electrical outputs, providing a route toward liquid-state sensing and soft electronic systems.

Exploiting heavy main-group centers to create three-dimensional binding environments in π-frameworks offers an underexplored strategy for controlling fullerene assembly and electronic function. Herein, we report the first isolable tristannosumanenes, obtained via a one-step multi-site tin insertion into a triphenylene precursor. Single-crystal analysis showed that the tetracoordinate tin centers arrange their exocyclic substituents alternately above and below the π-plane, generating substituent-defined binding pockets whose depth is shifting from 2.1 Å (methyl) to 4.3 Å (phenyl substitution). The methyl-substituted 2a binds C₆₀ in solution with a high association constant (K_a = 6.40 × 10⁵ M^-1), whereas DFT calculations reveal that deeper pockets do not enhance intrinsic affinity (ΔE = -0.25 vs. +1.39 kcal mol^-1). FP-TRMC measurements showed contrasting photoconductivity trends upon fullerene complexation-suppression for 2a⊃C₆₀ and enhancement for 2b⊃C₆₀-correlated with their divergent packing topologies (Pnma vs. P2/n). These results establish substituent engineering at tetracoordinate tin centers as a practical strategy for altering binding-pocket geometry, fullerene organization, and charge-transport behavior in heterasumanene-based π-systems.

Two-dimensional transition metal dichalcogenides (TMDCs) have recently emerged as promising defect qubit hosts due to their low nuclear spin density. Millisecond-scale spin coherence times were predicted for ideal model qubit systems under magnetic field strengths of a few teslas, where the magnetic noise due to the dilute nuclear spin bath was significantly suppressed. However, the effects of the specific defect structure and magnetic fields remain unexplored. Combining hybrid density functional theory and cluster correlation expansion, we investigate the spin decoherence of specific defect qubit candidates, which are a carbon radical ion (S = 1/2) and an antisite defect (S = 1), under varying magnetic field strengths. A key finding is that a spin in a TMDC undergoes early collapse of coherence (ECC) within a sub-microsecond timescale depending on the defect type, host material, and magnetic field. In particular, defect spins in a Mo-based TMDC show pronounced ECC over a broad range of magnetic field strengths, leading to a clear two-step decoherence process: (1) an initial sub-microsecond (T_ECC) decay driven by single nuclear spin dynamics, followed by (2) a slower millisecond-scale decay (T₂) arising from nuclear spin flip-flop interactions. Notably, at specific magnetic field strengths, coherence associated with the slower T₂ decay is completely suppressed due to enhanced nuclear spin modulation effects, leaving ECC as the dominant decoherence mechanism. These results identify ECC as a central feature of spin decoherence in TMDCs and highlight the interplay between defect characteristics and the nuclear spin environment in determining qubit coherence.

To overcome delayed vascularization and wet-state mechanical deterioration in critical-sized bone defect repair, we developed a composite scaffold inspired by the natural Haversian system. The scaffold features longitudinally interconnected primary channels surrounded by anisotropic micropores, forming a hierarchical network that enhances directional mass transport, tissue infiltration, and vascular ingrowth. Rather than adopting a uniform composition, we engineered a spatially heterogeneous distribution of inorganic components. While brushite and hydroxyapatite are integrated into the initial chitosan matrix, calcium phosphate is deposited via subsequent mineralization on the internal surfaces of the scaffold, providing widespread interfaces for cell adhesion and osteogenesis. Conversely, a tightly integrated silica-rich layer is selectively localized along the mechanically vulnerable primary-channel walls. This localized silica reinforcement, combined with the coordinated incorporation of calcium phosphates, significantly reinforces the scaffold's mechanical reliability in the wet state. Concurrently, the sustained release of bioactive calcium, phosphorus, and silicon species provides robust osteogenic and angiogenic cues. In vitro and in vivo evaluations demonstrated that this synergy of enhanced mass transport, localized mechanical reinforcement, and spatially programmed biochemical signals effectively promotes coupled vascularized bone regeneration. This study establishes an integrated compositional and structural design strategy, wherein spatially programmed simple constituents reconcile permeability, wet-state mechanical support, and biological activity for advanced bone repair.

Conjugated polymers are used to sort polychiral mixtures of single-walled carbon nanotubes (SWCNTs), generating highly valuable materials of precisely defined optical and electrical characteristics. However, the underlying interactions between these components are not understood to a sufficient extent, so to harvest a specific SWCNT chirality, a trial-and-error approach is usually utilized, which necessitates the use of a broad spectrum of conjugated polymers. Despite the labor- and cost-intensive nature of such a tactic, its success is still uncertain. In this study, we examined the interplay of a variety of synthesized conjugated polymers with SWCNTs to get a fundamental understanding of their modus operandi. We discovered that heteroatoms embedded in the polymers substantially enhanced the binding strength of the polymer molecules to SWCNTs. The performed multiscale calculations revealed that the presence of such elements increased the interaction between the polymer molecules and SWCNTs. Interestingly, the conjugated polymers exhibited a bifurcation phenomenon when free of heteroatoms. The robustness of the polymer/SWCNT hybrid hinged upon its assuming a particular initial orientation in space. Our findings provide insight into the design of polymers capable of strong and selective binding with specific types of SWCNTs in a reproducible manner. This insight is supposed to facilitate the long-awaited implementation of monochiral SWCNTs in a broad spectrum of applications.

Architected materials gain stiffness from beams, plates or minimal-surface shells, yet beam lattices lose efficiency to bending and nodal stress concentration and closed-cell lattices are difficult to manufacture and to clear of powder or resin. Open-cell minimal-surface shells print readily, but their zero mean curvature suppresses the stretching needed for hydrostatic load transfer. We make mean curvature the central design parameter and offset the limits of any single cubic constant-mean-curvature family by hybridization. Here we introduce an open-cell hybrid shell metamaterial combining four such families with differing wall spans and non-redundant load paths, Schwarz Primitive (SP), Schwarz Diamond (SD), Schoen I-graph wrapped polyhedron (IWP) and Schoen F-graph rhombic dodecahedron (FRD), whose non-zero curvature carries load by stretching rather than bending. A Bayesian surrogate search over 116 high-fidelity simulations identifies the optimal hybrid. At volume fraction 0.45 it reaches 97.3% of the isotropic Hashin-Shtrikman bulk-modulus reference for a porous solid, staying within 7% across 0.25 ≤ v ≤ 0.55 with only weak cubic anisotropy. Carbon-fiber-reinforced nylon specimens printed by desktop fused-deposition modeling reproduce the ranking and recover 82-89% of the corresponding specimen-scale predictions, with stiffness 28.8-35.5 GPa and peak compressive stress 205-231 MPa across printing and in-plane directions, 40% and 48% above the strongest single-family baseline in the printing direction. Static finite-element integration into a virtual-reality headset and smartwatch case indicates 45% and 63.5% mass reductions at matched stiffness or strength. Curvature-guided hybridization thus offers a manufacturable route to open-cell shell metamaterials approaching a declared isotropic Hashin-Shtrikman hydrostatic reference.

Biodegradable and bioresorbable rechargeable batteries are emerging as key enabling technologies for transforming the manner in which electronic systems are powered when device retrieval, recycling, or long-term persistence is a challenge or undesirable. This review integrates recent advances in materials engineering and artificial intelligence for creating "green-by-design" secondary batteries that operate safely in the environment and on/within living organisms for a desired timeline before naturally disintegrating into non-toxic materials. The discussion first surveys sustainable chemistries and architectures that collectively enable rechargeable operation and degradation of spent batteries into benign ions and small molecules. Subsequent sections examine how established lithium-ion battery informatics can be repurposed for biodegradable alternatives. Specifically, these sections explore how workflows for property prediction, multi-objective optimization, and literature mining can integrate explicit constraints regarding battery lifetime and environmental toxicity. The review concludes by outlining grand challenges and research priorities required to transition biodegradable secondary batteries from laboratory exemplars into practical power sources intrinsically aligned with their biological and ecological contexts.

Organic-inorganic hybrid manganese halides (OIMnHs) are promising stimuli-responsive materials due to their structural tunability and rich photophysical properties. However, current research relies largely on empirical screening of numerous organic cations, and a rational design model that decouples the multiple structural variables affecting luminescence remains scarce. Here, a site-specific chemical modification strategy on a 2-amino-3,5-dimethylpyridinium scaffold [A]2[MnCl₄] is proposed to systematically decouple the effects of the anionic halide site (X-site) and the organic cation site (A-site). Through two orthogonal bromination pathways: substituting Cl^- with Br^- at the X-site and -CH3 with -Br at the functional group of the A-site, six Mn-based hybrid crystals are synthesized, which form a tightly interlinked comparative platform with minimal structural perturbation. Although A-site Br substitution reduces the PLQY from 32.4% (35DM-C) to approximately 5% (3BG and 5BG), it simultaneously imparts distinctive humidity-responsive behaviors. At 75% relative humidity, 3BG and 5BG undergo humidity-induced structural transformations into 3BY and 5BR, respectively, boosting PLQY dramatically (∼11-fold) to 55.0% and 52.9%. Taking advantage of the humidity response and broad spectral coverage of these materials, their potential for information encryption and high-color-rendering white-light illumination is further demonstrated, achieving a color-rendering index of 91.6. Systematic experiments and theoretical calculations reveal that local chemical modification of the organic cation regulates excited-state dynamics, enhancing radiative transitions and suppressing nonradiative pathways by tuning weak-interaction networks, which in turn governs the humidity-induced structural transformation and luminescence switching. This stepwise, interlocking research framework enables clear structure-property correlations.

Electrochemical ion diodes (CAPodes) integrate charge storage with directional ion transport, but the rectifying phase in nickel foam-based CAPodes remains unresolved. Here we show that rectification arises predominantly from the reversible OH^--coupled β-Ni(OH)₂/β-NiOOH redox transition rather than from metallic Ni itself. In situ Raman and ex situ XPS analyses reveal potential-dependent hydroxide/oxyhydroxide conversion on nickel foam, and the same rectification function can be reconstructed on an inert Ti substrate by electrodepositing β-Ni(OH)₂. The optimized electrode delivers a rectification ratio I (RRI) of 303.6 and a rectification ratio II (RRII) of 97.1%, outperforming commercial nickel foam, while the corresponding CAPode provides 123.7 F g^-1 at 1 A g^-1 and supports stable OR/AND logic outputs. The rectification behavior is further reproduced in β-Ni(OH)₂ powders prepared via co-precipitation, confirming that the rectification originates from the active phase rather than the substrate or synthesis route. These findings establish β-Ni(OH)₂ as the key electroactive phase in nickel-based CAPodes and provide a mechanism-guided strategy for designing redox-active ion diodes.

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