The artificial hydrological cycle built by using deliquescent calcium chloride enables self-operation of a transpiration-driven electrokinetic power generator.

Nano-hydroelectric technology utilizes hydraulic flow through electronically conducting nanomaterials to generate electricity in a simple, renewable, ubiquitous, and environmentally friendly manner. Up to date, several designs of nano-hydroelectric devices have...

use of unique chemical, optical, and electrical properties of each metal component, one can obtain a homo-or heteromixture with unusual optical, electrical, chemical, and catalytic behaviors. On the basis of this knowledge, bi-, tri-, and even tetrametallic nanoscale structures have been synthesized by incorporating several metals into a single structure through various synthetic techniques. The controlled combination of multi-metals at the nanoscale offers an effective way of tuning the chemical and physical properties of nanostructures either by facilitating hybrid chemical, electronic, and magnetic interactions between metal components or by combining different properties associated with each pure component. These properties make multimetallic nanostructures a promising system for diverse applications. In particular, multimetallic nanostructures with spatial arrangement can advantageously be applied to electronics for sensing, charge transfer, and heat transfer behaviors.Controlled synthesis and positioning of multimetallic nanostructures have become increasingly important for systematic study. To date, several methods have been developed for ordered polyelemental nanostructures. For example, important advances have been made in ink-jet printing and blockcopolymer methods, in which two or three metal precursors are reduced in patterned polymer ink or a specific part of a block copolymer to produce bi-or tri-metallic nanospheres. [2] However, these approaches are considerably limited to the number of combinations of metals depending on the compatibility of elements and to the complex shape control of the nanostructures, which can change according to the demands of applications such as line shapes in electronics.In the present work, we developed a new method to fabricate a 3D polyelemental nanopattern with tunable combination, composition, shape, and array by using low-energy Ar + ion plasma. By using this approach, we achieved a 3D polyelemental nanopattern with high resolution (≈10 nm) and high aspect ratio (>20). Our system overcame limitations in terms of shape and arrangement and was adoptable to any metal combination. This method provides a simple and general approach for the fabrication of multimetallic nanopatterns regardless of the synthetic conditions of various metals. Furthermore, the structure formation during secondary sputtering was understood, andThe development of complex nanostructures containing a homo-and heteromixture of two or more metals is a considerable challenge in nanotechnology. However, previous approaches are considerably limited to the number of combinations of metals depending on the compatibility of elements, and to the complex shape control of the nanostructure. In this study, a significant step is taken toward resolving these limitations via the utilization of a low-energy argon-ion bombardment. The multilayer films are etched and re-sputtered on the sidewall of the pre-pattern, which is a secondary sputtering phenomenon. In contrast to the precursor mixing method, most metal...

Key pointsr Cellular stimuli can modulate the ion selectivity of some anion channels, such as CFTR, ANO1 and the glycine receptor (GlyR), by changing pore size.r Ion selectivity of CFTR, ANO1 and GlyR is critically affected by the electric permittivity and diameter of the channel pore.r Pore size change affects the energy barriers of ion dehydration as well as that of size-exclusion of anion permeation.r Pore dilatation increases the bicarbonate permeability (P HCO 3 /Cl ) of CFTR, ANO1 and GlyR. r Dynamic change in P HCO 3 /Cl may mediate many physiological and pathological processes.Abstract Chloride (Cl − ) and bicarbonate (HCO 3 − ) are two major anions and their permeation through anion channels plays essential roles in our body. However, the mechanism of ion selection by the anion channels is largely unknown. Here, we provide evidence that pore dilatation increases the bicarbonate permeability (P HCO 3 /Cl ) of anion channels by reducing energy barriers of size-exclusion and ion dehydration of HCO 3 − permeation. Molecular, physiological and computational analyses of major anion channels, such as cystic fibrosis transmembrane conductance regulator (CFTR), anoctamin-1(ANO1/TMEM16A) and the glycine receptor (GlyR), revealed that the ion selectivity of anion channels is basically determined by the electric permittivity and diameter of the pore. Importantly, cellular stimuli dynamically modulate the anion selectivity of CFTR and ANO1 by changing the pore size. In addition, pore dilatation by a mutation in the pore-lining region alters the anion selectivity of GlyR. Changes in pore size affected not only the energy barriers of size exclusion but that of ion dehydration by altering the electric permittivity of water-filled cavity in the pore. The dynamic increase in P HCO 3 /Cl by pore dilatation may have many physiological and pathophysiological implications ranging from epithelial HCO 3 − secretion to neuronal excitation.I. Jun, M. Cheng and E. Sim contributed equally to this work.

Plasmonic metal nanoparticles absorb light energy and release the energy through radiative or nonradiative channels. Surface catalytic reactions take advantage of the nonradiative energy relaxation of plasmons with enhanced activity. Particularly, binary nanoparticles are interesting because diverse integration is possible, consisting of a plasmonic part and a catalytic part. Herein, we demonstrated ethanol dehydrogenation under light irradiation using Ag–Ni binary nanoparticles with different shapes, snowman and core–shell, as plasmonic catalysts. The surface plasmon formed in the Ag part enhanced the surface catalytic reaction that occurred at the Ni part, and the shape of the nanoparticles affected the extent of the enhancement. The surface plasmon compensated the thermal energy required to trigger the catalytic reaction. The absorbed light energy was transferred to the catalytic part by the surface plasmon through the nonradiative hot electrons. The effective energy barrier was greatly reduced from 41.6 kJ/mol for the Ni catalyst to 25.5 kJ/mol for the core–shell nanoparticles and 22.3 kJ/mol for the snowman-shaped nanoparticles. These findings can be helpful in designing effective plasmonic catalysts for other thermally driven surface reactions.

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Efficient conversion of ethane into valuable materials is important with the availability of new natural gas resources. Recently, metal−organic frameworks (MOFs) with open iron sites (i.e., Fe 0.1 Mg 1.9 -MOF-74) have been shown to be promising material for catalyzing ethane to ethanol. In this computational study, various size-matching ligands are inserted into the Fe 0.1 Mg 1.9 -MOF-74 structure to further optimize this reaction. Our density functional theory calculations show that the presence of ligands enhances the binding affinity of the oxygen atoms of N 2 O to the iron atoms in the framework, thereby leading to an improvement in the oxidizing process. Furthermore, the reaction pathways for the new structures show reduced enthalpy barrier in the ratedetermining step in the oxidation of ethane reaction cycle compared to the original Fe 0.1 Mg 1.9 -MOF-74. These findings provide ways in which the performance of the Fe 0.1 Mg 1.9 -MOF-74 can be optimized for next-generation catalysts.

Among various class of materials, metal organic frameworks (MOFs) are one of the most promising candidates for CO2 capture from flue gases. In particular, M-MOF-74, where M represents different metals, are equipped with open metal sites that can lead to very high CO2 uptake at postcombustion flue gas conditions. However, these structures are known to have poor CO2 capture performance under humid conditions as water molecules bind strongly to the unsaturated metal sites, outcompeting the CO2. In this computational study, a pore space partition strategy is employed through a symmetry-matching regulated ligand insertion within the Mg-MOF-74 and Zn-MOF-74 structures, which mitigates the deterioration effect of water. In the case of Zn-MOF-74, higher selectivity as well as larger CO2 uptake in binary mixture conditions is obtained, thereby demonstrating that reduction in the pore size of MOFs can serve as viable strategy to capture CO2 under humid postcombustion conditions.