Reversible Plasmonic Circular Dichroism <i>via</i> Hybrid Supramolecular Gelation of Achiral Gold Nanorods

The fabrication of chiroptical plasmonic nanomaterials such as chiral plasmonic gold nanorods (GNRs) has been attracting great interest. Generally, in order to realize the plasmonic circular dichroism (PCD) from achiral GNRs, it is necessary to partially replace the surface-coated cetyltrimethylammonium bromide with chiral molecules. Here, we present a supramolecular approach to generate and modulate the PCD of GNRs through the hybrid gelation of GNRs with an amphiphilic chiral dendron gelator. Upon gelation, the PCD could be produced and further regulated depending on the ratio of the dendrons to GNRs. It was revealed that the wrapping of the self-assembled nanofibers around the GNRs is crucial for generating the PCD. Furthermore, the hybrid gel underwent a thermotriggered gel–sol and sol–gel transformation, during which the PCD can disappear (solution) and reappear (gel), respectively, and such process can be repeated many times. In addition, the hybrid gel could also undergo shrinkage upon addition of a slight amount of Mg²⁺ ions, during which the PCD disappeared also. Thus, through the gel formation and subsequent metal ion- or temperature-triggered phase transition, PCD can be reversibly modulated. The results not only clarified the generation mechanism of PCD from the achiral GNRs without the chiral modification on the surface but also offered a simple and efficient way to modulate the PCD

Kinetic Charging Inversion in Ionic Liquid Electric Double Layers

The charging kinetics of electric double layers (EDLs) has a pivotal role in the performance of a wide variety of nanostructured devices. Despite the prevalent use of ionic liquids as the electrolyte, relatively little is known on the charging behavior from a microscopic perspective. Here, we study the charging kinetics of ionic liquid EDLs using a classical time-dependent density functional theory that captures the molecular excluded volume effects and electrostatic correlations. By examining variations of the ionic density profiles and the charging density in response to an electrode voltage, we find that at certain conditions, the electrode charge shows a rapid surge in its initial response, rises quickly to the maximum, and then slowly decays toward equilibrium. The electrode charge and voltage may have opposite signs when the cell width is commensurate with the layer-by-layer ionic distributions. This unusual charging behavior can be explained in terms of the oscillatory structure of ionic liquids near the electrodes

Effects of chain length and anions on ion transport in PEO-lithium salt systems

Understanding the transport mechanism of Li+ in solid polymer electrolytes is beneficial for improving the safety and energy density of lithium-ion batteries. In this work, we investigate the effects of chain length of poly (ethylene oxide) (PEO) and anions (TfO-, TFSI-, PFSI-) on ion transport properties in PEO-lithium salt systems using all-atom molecular dynamics simulations. We found that the Li+ and PEO monomers are co-diffusion, regardless of the PEO chain length and the type of anion. The diffusion of Li+ becomes slower with PEO chain length and reaches an asymptotic value. In addition, the motion of the Li+ is the slowest in PEO/LiTfO systems. We conclude that the free volume of the systems plays a decisive role in the transport properties of Li+.</p

Additional file 1 of Transcriptome exploration of ferroptosis-related genes in TGFβ- induced lens epithelial to mesenchymal transition during posterior capsular opacification development

Supplementary Material 1

Self-Assembled Single-Walled Metal-Helical Nanotube (<b>M‑HN</b>): Creation of Efficient Supramolecular Catalysts for Asymmetric Reaction

Ever since the axial chiral catalysts were developed for asymmetric reactions with excellent chiral discrimination and high efficiencies, the interest in the supramolecular catalyst has also been extensively investigated. Here, with a hint from the typical molecular catalyst, we developed a series of metal-coordinated nanotube (M-helical nanotube, <b>M-HN</b>) catalysts for asymmetric reactions. The <b>M-HN</b> catalyst was fabricated on the basis of the self-assembly of an l-glutamic acid terminated bolaamphiphile, which formed a single-walled nanotube. On one hand, through the coordination of transition metal ions with the carboxylic acid groups on the nanotube surface, a wide variety of single-walled <b>M-HN</b> catalysts could be fabricated, in which the coordination sites could serve as the catalytic sites. On the other hand, using a slight amount of these catalysts, significant reactivity and enantioselectivity were realized for certain asymmetric reactions under mild conditions. Remarkably, <b>Bi­(III)-HN</b> could catalyze the asymmetric Mukaiyama aldol reaction with high enantioselectivity (up to 97% ee) in an aqueous system; <b>Cu­(II)-HN</b> catalyzed the asymmetric Diels–Alder reaction with up to 91% ee within 60 min. It was suggested that a synergetic effect of the aligned multicatalytic sites and stereochemical selectivity of the <b>M-HN</b> lead to an excellent catalytic performance. Through this work, we proposed a new concept of a single-walled nanotube as catalyst and showed the first example of nanotube catalysts presenting high reactivity and enantioselectivity that rivaled a chiral molecular catalyst

Adsorption of a Polyelectrolyte Chain at Dielectric Surfaces: Effects of Surface Charge Distribution and Relative Dielectric Permittivity

The characteristics of a surface, such as surface charge distribution and permittivity, play significant roles in polyelectrolyte (PE) adsorption. However, systematic studies of these effects are rare in the literature. In this work, we employ a local lattice Monte Carlo algorithm to investigate the effects of dielectric contrast, charge fraction, and surface charge density on the adsorption behavior of a PE chain onto surfaces with different charge distributions. We consider three surface charge distributions: uniform (smeared), regular (periodic), and random. For the same total surface charge, the random charge distribution results in the strongest PE adsorption, while the uniform distribution shows the weakest. In the absence of dielectric contrast, the adsorption behaviors of a PE near the regularly charged surface are similar to those near the uniformly charged surface. In the presence of dielectric contrast, the image repulsion inhibits PE adsorption onto the uniformly charged surface. Surprisingly, surfaces with discrete charge distributions (regular and random) exhibit enhanced adsorption compared to that of the case with no image charge. In addition, the competition between image charge repulsion and electrostatic attraction from the surface results in nonmonotonic variation of the adsorbed amount with the PE charge fraction

Evolution of Useless Iron Rust into Uniform α‑Fe₂O₃ Nanospheres: A Smart Way to Make Sustainable Anodes for Hybrid Ni–Fe Cell Devices

The large amount of iron rust yielded in steel industries is undoubtedly a useless and undesired product since its substantial formation and recycle/smelting would give rise to enormous financial costs and environmental pollution issues. To best reuse such rusty wastes, we herein propose a smart and applicable method to convert them into uniform α-Fe₂O₃ nanospheres. Only after a simple and conventional hydrothermal treatment in HNO₃ solution, nearly all of the iron rust can evolve into sphere-like α-Fe₂O₃ products with a typical size of ∼30 nm. When serving as actives for electrochemical energy storage, the <i>in situ</i> generated α-Fe₂O₃ nanospheres exhibit prominent anodic performance, with a maximum specific capacity of ∼269 mAh/g at ∼0.3 A/g, good rate capabilities (∼67.3 mAh/g still retains even at a high rate up to 12.3 A/g), and negligible capacity degradation among 500 cycles. Furthermore, by paring with activated carbons/Ni cathodes, a unique full hybrid Ni–Fe cell is constructed. The assembled full devices can be operated reversibly at a voltage as high as ∼1.8 V in aqueous electrolytes, capable of delivering both high specific energy and power densities with maximum values of ∼131.25 Wh/kg and ∼14 kW/kg, respectively. Our study offers a scalable and effective route to transform rusty wastes into useful α-Fe₂O₃ nanospheres, providing an economic way to make sustainable anodes for energy-storage applications and also a platform to develop advanced Fe-based nanomaterials for other wide potential applications

Molecular Theory for Electrokinetic Transport in pH-Regulated Nanochannels

Ion transport through nanochannels depends on various external driving forces as well as the structural and hydrodynamic inhomogeneity of the confined fluid inside of the pore. Conventional models of electrokinetic transport neglect the discrete nature of ionic species and electrostatic correlations important at the boundary and often lead to inconsistent predictions of the surface potential and the surface charge density. Here, we demonstrate that the electrokinetic phenomena can be successfully described by the classical density functional theory in conjunction with the Navier–Stokes equation for the fluid flow. The new theoretical procedure predicts ion conductivity in various pH-regulated nanochannels under different driving forces, in excellent agreement with experimental data

Self-Assembled Polydiacetylene Vesicle and Helix with Chiral Interface for Visualized Enantioselective Recognition of Sulfinamide

An l-glutamic acid terminated amphiphilic diacetylene was designed and found to self-assemble into vesicles in water and supramolecular gel with helical structures in mixed methanol/water solvent. Both the vesicles and the helices underwent topochemical photopolymerization under UV irradiation and changed to a blue color. During the self-assembly and photopolymerization, the chirality of localized l-glutamic acid was successfully transferred to polydiacetylene (PDA), which resulted in obvious CD signals in the PDA blue phase. Interestingly, the CD signals for PDA vesicles and helices were opposite due to the different packing modes in the PDA skeleton. However, although these two assembly systems own opposite supramolecular chirality, both of them showed the same enantioselective recognition of sulfinamide enantiomers, in which the assemblies with <i>S</i>-enantiomer turned red while the other remained blue in the presence of the <i>R</i>-enantiomer. It is suggested that the chiral interface composed of l-glutamic acid played an important role in the enantioselective recognition. This work revealed the function of molecular and supramolecular chirality in the supramolecular self-assembly system