Small Methods最新文献

While extensive efforts have focused on mitigating non-uniform lithium deposition, lithium stripping-an equally critical process governing reversibility and Coulombic efficiency-remains poorly understood, particularly in relation to electrolyte chemistry. Here, we demonstrate that lithium stripping behavior is governed by the time-dependent evolution of the solid-electrolyte interphase (SEI), which varies systematically across electrolyte systems. Using correlative scanning electron microscopy and cryogenic transmission electron microscopy, we reveal that different electrolytes generate distinct spatial distributions of SEI thickness along lithium dendrites, leading to fundamentally different stripping pathways. Electrolytes exhibiting slow interfacial resistance growth form spatially homogeneous SEI shells and enable uniform lithium stripping, whereas electrolytes with rapid SEI growth develop pronounced SEI heterogeneity, inducing preferential stripping near the current collector. Extending this analysis across six representative electrolyte systems, we identify a strong correlation between the SEI thickness distribution, interfacial resistance growth rate, and stripping behavior. These findings establish a physicochemical framework linking electrolyte-dependent SEI evolution to lithium stripping dynamics and provide design principles for optimizing operating protocols to maximize lithium metal reversibility.

Synergistic nanotrap polymeric adsorbents, by integrating multiple cooperative interaction modes within a single polymer network, can effectively overcome the limitations of conventional single-site sorbents in complex environments. This review examines and summarizes the latest research advances in such systems, covering both non-porous and porous polymers, and systematically correlates polymer molecular design with adsorption performance toward organic pollutants, aqueous ionic pollutants, and radioactive contaminants. We place particular emphasis on how hydrogen bonding, electrostatic interactions, π-π stacking, coordination, hydrophobic effects, and halogen bonding are introduced and integrated within polymer backbones to construct multisite nanotraps, thereby enhancing adsorption capacity, kinetics, selectivity, and resistance to interference. Finally, we discuss the key challenges and future opportunities associated with achieving deeper mechanistic understanding, operando characterization under realistic conditions, and the scalable processing and engineering application of synergistic nanotrap polymeric adsorbents, with the aim of advancing their practical implementation in sustainable environmental remediation.

Phase control of polymorphic materials is important yet challenging due to the vast synthesis parameter space and the sensitivity of certain phases to specific conditions. Recent advances in integrating artificial intelligence with laboratory automation offer promising solutions to address experimentation challenges like this. In this work, we developed an active learning-guided robotic synthesis workflow to achieve phase control during co-precipitation synthesis. This workflow was demonstrated using FeC₂O₄·2H₂O, a polymorphic compound with diverse applications. The optimal synthesis conditions for obtaining pure α-FeC₂O₄·2H₂O were identified using Bayesian optimization. Building on this, an active learning-guided workflow that can predict phase outcomes based on given synthesis parameters was showcased, enabling more efficient exploration of selective synthesis. The influence of synthesis parameters on the morphology of FeC₂O₄·2H₂O was also preliminarily examined. This study highlights how artificial intelligence with robotic synthesis can accelerate the uncovering of synthesis-phase relationships and advance controllable material synthesis.

Poly(ethylene glycol) lipids (PEG-lipids) are widely used to stabilize mRNA lipid nanoparticles, yet repeat dosing can reveal delivery trade-offs and immune liabilities arising from limited molecular definition at the nano-bio interface. This Perspective reframes the PEG dilemma not as a binary materials choice but as a surface-engineering problem defined by measurable interfacial variables. We summarize PEG-centric design levers, including chain length, terminal chemistry, PEG fraction, and mixed-length designs, and discuss recent progress in PEG alternatives alongside key translational constraints. A complementary strategy is to increase the molecular definition of PEG interfaces through discrete-molar-mass PEG-lipids and topology control. Such approaches may narrow epitope heterogeneity and clarify structure-function relationships across key interfacial properties, including surface density and spacing, dissociation and exchange kinetics, and epitope persistence. Improved molecular definition will not eliminate PEG-directed immunity in every setting, but it can improve predictability and manufacturing reproducibility, and may broaden the accessible design space for repeat-dosing mRNA therapeutics. Finally, we discuss how interface design can be paired with immune-aware dosing and monitoring strategies to support durable clinical efficacy and safety.

Aqueous zinc batteries have emerged as promising candidates for safe and sustainable energy storage. However, their practical application is severely limited by zinc corrosion, hydrogen evolution, and non-uniform dendritic growth stemming from interfacial instability and water-induced side reactions. Herein, we report dimethyl isosorbide (DMI) as an effective electrolyte additive that simultaneously regulates zinc ion solvation structure and stabilizes the zinc/electrolyte interface. DMI modulates the solvation shell by restructuring the hydrogen-bonding network while adsorbing onto zinc surfaces to form a protective molecular layer. Comprehensive spectroscopic analyses and molecular dynamics simulations reveal weakened zinc solvation power and reduced H₂O activity in the presence of DMI, leading to suppression of zinc corrosion. Notably, DMI induces a capacity-dependent crystallographic zinc evolution, enabling a transition from preferential initial growth to stable deposition at higher areal capacities. Electrochemical evaluations demonstrate prolonged cycling stability, near-unity Coulombic efficiency, and robust performance under high current density and high areal capacity conditions. Operando optical visualization and morphology analyses confirm highly uniform, dendrite-free zinc deposition and nearly reversible zinc plating/stripping. This work highlights an effective electrolyte engineering strategy for stabilizing zinc metal anodes and advancing the practical viability of aqueous zinc batteries.

The electromagnetic interference (EMI) shielding performance of Cu@Ag core-shell composites is significantly determined by the silver shell morphology and core-shell interface properties. However, in-situ regulation of these features remains challenging due to the unclear formation mechanism for the Ag shell. Herein, we present a ligand-regulated synthesis in which ammonia is employed to precisely control the growth of the silver shell during liquid-phase reduction. Ammonia forms stable [Ag(NH₃)₂]⁺ complexes with silver ions, which modify the deposition kinetics. Such a shift transitions the coating process from rapid, anisotropic plating to controlled, uniform growth. Consequently, the morphology of the silver shell evolves from plate-like to particle-like structure, accompanied by the formation of an Ag-Cu transition layer at the core-shell boundary. These structural refinements dramatically reduce the electrical resistivity from 6.42 Ω·cm to 6.37 × 10^{- 4} Ω·cm. And the optimized structure exhibits superior EMI shielding effectiveness of 85.4 dB across 5.85-18 GHz range, with a peak radiation suppression of 26.8 dB. Moreover, the SE is further enhanced to 101.7 dB through a stratified stacking strategy. This work demonstrates ligand regulation as an effective strategy for enhancing EMI shielding performance.

Research on graphene transfer technology is very important for the practical applications of graphene films. Among the graphene transfer schemes, the electrochemical bubbling process is an efficient and scalable method. However, since this method involves the rapid exfoliation of graphene, ensuring the quality of the bubbling-transfer graphene remains a challenge. Herein, glucose is introduced into the bubbling solution, and its intercalation effect between graphene and the metal substrate weakens the coupling between them, making graphene easier to exfoliate. Graphene grown on a variety of different substrates is transferred by the glucose-assisted electrochemical bubbling method. The single-layer and bilayer graphene transferred by glucose assistance show excellent electrical properties, further demonstrating the high quality of graphene. This work provides a universal method for the transfer of graphene, which is expected to become the basis for its future applications.

Hydrophobic cathode interlayers (CIL) can prevent water molecules into active layer, resulting in an enhanced long-term stability for organic solar cells (OSCs). However, the intrinsic liposolubility limits the application of hydrophobic CIL in conventional OSC devices. Herein, we report a series of novel hydrophobic water/alcohol-soluble conjugated polymers (H-WSCPs) (PFN-F50, PFN-F25, and PFN-F12.5) through simple side chain engineering. H-WSCPs combining alcohol solubility and hydrophobicity have potential application for improvement in the stability of conventional OSC devices. The solubility in alcohol solvents avoids erosion of the active layer during the processing. These fluorinated H-WSCPs present almost unchanged photoelectric characteristics compared with PFN-Br, achieving a comparable power conversion efficiency with that of PFN-Br-based OSCs in conventional devices. More importantly, through the introduction of the fluorinated alkyl chain, these polymers obtain excellent hydrophobicity, resulting in an increased water-resistance capability. CIL adopting fluorinated H-WSCPs can effectively prevent moisture from destroying the active layer, leading to an extended lifetime for OSC devices. After illumination for 600 h, the PFN-F25 conventional device maintained 75% of the initial value. This work provides a simple method to design hydrophobic CIL for conventional OSCs with high stability.

Protonic ceramic fuel cells (PCFCs) are promising electrochemical power generation devices, yet the ion diffusion behavior within their electrolyte bulk under real operating conditions remains poorly understood, hindering further development from both materials design and operation parameters optimization. This study tackles this issue of the benchmark protonic BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3-δ (BZCYYb) electrolyte using a combined tool of electrochemical impedance spectroscopy (EIS), single cell testing under varying conditions, H₂O-temperature-programmed desorption coupled with mass spectrometry, time-of-flight secondary ion mass spectrometry characterization, and theoretical calculations. Before the hydration, EIS test confirms BZCYYb is an excellent oxygen-ion conductor at intermediate temperatures. Upon exposure to humidified air, it transitions to a mixed proton and oxygen-ion conductor due to water uptake. Under dry hydrogen atmosphere, protonation proceeds via a newly identified mechanism, hydrogenation of oxygen at grain boundaries, along with hydration from in situ water generation at the cathode during polarization, eliminating the need for pre-humidified fuel gas when operating on hydrogen. At temperatures above 600°C, dehydration dominates, even in humidified conditions, further shifting the electrolyte to a mixed proton and oxygen-ion conductor. These findings offer critical insights for the ion diffusion in protonic perovskites and facilitate the rational design of next-generation PCFCs.

Miniaturization and rising power densities exacerbate localized hot spots on electrically insulating substrates, where heat spreads non-selectively. A boron nitride nanotube (BNNT)/epoxy "thermal guide" is developed for selective, geometry-programmable heat routing. A viscosity-tuned BNNT/epoxy ink is processed by micro-nozzle extrusion; confinement-induced shear aligns BNNTs into an orientation-defined architecture, as confirmed by small-angle X-ray scattering and supported by flow simulations identifying nozzle size as a key alignment control. Aligned bulk composites exhibit pronounced in-plane anisotropy (k_y/k_x ≈ 2.53; 2.96 vs 1.17 W m^{- 1} K^{- 1}, parallel vs transverse to the fiber direction), and infrared thermography visualizes alignment-guided heat transport: at 5 cm from a 70°C source, the y-axis-oriented specimen reaches 55.8°C after 30 s, compared with 48.1°C for the x-axis-oriented specimen. Dielectric integrity is retained at network-forming loadings, with volume resistivity of ∼10¹³ Ω·m at 20 wt.% BNNT and low dielectric loss. Dispenser printing enables ∼200 µm-wide guides; contacting a 70°C source at the guide terminus produces >20°C terminal contrast relative to the surrounding region outside the printed pattern. This method therefore enables electrically safe thermal routing to guide heat from a localized source to a target region while suppressing parasitic lateral diffusion into heat-sensitive areas.