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ACS Nano Jun 2024Solid-state nanochannels (SSNs) have emerged as promising platforms for controlling ionic transport at the nanoscale. SSNs are highly versatile, and this feature can be...
Solid-state nanochannels (SSNs) have emerged as promising platforms for controlling ionic transport at the nanoscale. SSNs are highly versatile, and this feature can be enhanced through their combination with porous materials such as Metal-Organic Frameworks (MOF). By selection of specific building blocks and experimental conditions, different MOF architectures can be obtained, and this can influence the ionic transport properties through the nanochannel. Herein, we study the effects of confined synthesis of Zr-based UiO-66 MOF on the ion transport properties of single bullet-shaped poly(ethylene terephthalate) (PET) nanochannels. We have found that emerging textural properties from the MOF phase play a determinant role in controlling ionic transport through the nanochannel. We demonstrate that a transition from ion current saturation regimes to diode-like regimes can be obtained by employing different synthetic approaches, namely, counterdiffusion synthesis, where MOF precursors are kept separate and forced to diffuse through the nanochannel, and one-pot synthesis, where both precursors are placed at both ends of the channel. Also, by considering the dependence of the charge state of the UiO-66 MOF on the protonation degree, pH changes offered a mechanism to tune the iontronic output (and selectivity) among different regimes, including anion-driven rectification, cation-driven rectification, ion current saturation, and ohmic behavior. Furthermore, Poisson-Nernst-Planck (PNP) simulations were employed to rationalize the different iontronic outputs observed experimentally for membranes modified by different methods. Our results demonstrate a straightforward tool to synthesize MOF-based SSN membranes with tunable ion transport regimes.
PubMed: 38941562
DOI: 10.1021/acsnano.4c04435 -
ACS Nano Jun 2024Layered membranes assembled from two-dimensional (2D) building blocks such as graphene oxide (GO) are of significant interest in desalination and osmotic power...
Layered membranes assembled from two-dimensional (2D) building blocks such as graphene oxide (GO) are of significant interest in desalination and osmotic power generation because of their ability to selectively transport ions through interconnected 2D nanochannels between stacked layers. However, architectural defects in the final assembled membranes (e.g., wrinkles, voids, and folded layers), which are hard to avoid due to mechanical compliant issues of the sheets during the membrane assembly, disrupt the ionic channel pathways and degrade the stacking geometry of the sheets. This leads to degraded ionic transport performance and the overall structural integrity. In this study, we demonstrate that introducing in-plane nanopores on GO sheets is an effective way to suppress the formation of such architectural imperfections, leading to a more homogeneous membrane. Stacking of porous GO sheets becomes significantly more compact, as the presence of nanopores makes the sheets mechanically softer and more compliant. The resulting membranes exhibit ideal lamellar microstructures with well-aligned and uniform nanochannel pathways. The well-defined nanochannels afford excellent ionic conductivity with an effective transport pathway, resulting in fast, selective ion transport. When applied as a nanofluidic membrane in an osmotic power generation system, the holey GO membrane exhibits higher osmotic power density (13.15 W m) and conversion efficiency (46.6%) than the pristine GO membrane under a KCl concentration gradient of 1000-fold.
PubMed: 38941515
DOI: 10.1021/acsnano.4c04493 -
The Journal of Chemical Physics Jun 2024The surfaces of many minerals are covered by naturally occurring cations that become partially hydrated and can be replaced by hydronium or other cations when the...
The surfaces of many minerals are covered by naturally occurring cations that become partially hydrated and can be replaced by hydronium or other cations when the surface is exposed to water or an aqueous solution. These ion exchange processes are relevant to various chemical and transport phenomena, yet elucidating their microscopic details is challenging for both experiments and simulations. In this work, we make a first step in this direction by investigating the behavior of the native K+ ions at the interface between neat water and the muscovite mica (001) surface with ab-initio-based machine learning molecular dynamics and enhanced sampling simulations. Our results show that the desorption of the surface K+ ions in pure ion-free water has a significant free energy barrier irrespective of their local surface arrangement. In contrast, facile K+ diffusion between mica's ditrigonal cavities characterized by different Al/Si orderings is observed. This behavior suggests that the K+ ions may favor a dynamic disordered surface arrangement rather than complete desorption when exposed to deionized water.
PubMed: 38940541
DOI: 10.1063/5.0217720 -
Small (Weinheim An Der Bergstrasse,... Jun 2024Salt deposition is a disturbing problem that limits the development of passive solar-driven interfacial evaporation. Inspired by the passive fluid control mechanism of...
Salt deposition is a disturbing problem that limits the development of passive solar-driven interfacial evaporation. Inspired by the passive fluid control mechanism of the Tesla valve, a novel solar evaporator is proposed with a Tesla valve-like water transport structure to prevent salt accumulation at the evaporation interface. A unique "ion diode" salt resistance of this evaporator is significantly achieved by optimizing the two asymmetric water transport structures, consisting of one Tesla valve-like side and one wide-leg side, which establish a reverse-suppressing and forward-accelerating water transport channel. In contrast to the limited ion migration of the typical symmetric solar evaporator, such a channel caused by the water/salt ions transport difference between two water supply structures, reinforces the water/salt ions supply on the wide-leg side, thus leading to an apparent unidirectional salt ions migration from the wide-leg side to bulk water through the Tesla valve-like side. Consequently, an evaporation rate of 3.25 kg m h and a conversion efficiency of 83.27% under 2 suns are achieved in 16 wt% NaCl solution. The development of the Tesla Valve-like evaporator provides a new perspective for solving salt deposition and realizing scalable applications of solar-driven interfacial evaporation.
PubMed: 38940231
DOI: 10.1002/smll.202403606 -
Advanced Materials (Deerfield Beach,... Jun 2024The 329-type bismuth (Bi)-based metal halide (MH) polycrystalline films have potential to be applied in the new generation of X-ray imaging technology owing to high...
The 329-type bismuth (Bi)-based metal halide (MH) polycrystalline films have potential to be applied in the new generation of X-ray imaging technology owing to high X-ray absorption coefficients and excellent detection properties. However, the mutually independent [BiX] units and numerous grain boundaries in the material lead to low carrier transport and collection capabilities, severe ion migration, large dark currents, and poor response uniformity. Here, a new multi-phenyl ring methyltriphenylphosphonium (MTP) is designed to optimize the energy band structure. For the first time, the coupling between the A-site cation and [BiX] is realized, making it the main contributor to the conduction band minimum (CBM), getting rid of dilemma that carrier transport is confined to [BiX]. Further, the preparation of MTPBiI amorphous large-area wafer is achieved by melt-quenching; the steric hindrance effect improves stability, increases ion migration energy, and promotes response uniformity (14%). Moreover, the amorphous structure takes advantage of A-site cation participation in the conductivity, achieving a record sensitivity (7601 µC Gy cm) and low dark current (≈0.11 nA) in the field of amorphous X-ray detection, and features low-temperature large-area preparation. Ultimately, designing amorphous array imaging devices that exhibit excellent response uniformity and potential imaging capabilities is succeeded here.
PubMed: 38940075
DOI: 10.1002/adma.202406128 -
BMC Plant Biology Jun 2024Salt is an important factor that affects crop productivity. Plant hexokinases (HXKs) are key enzymes in the glycolytic pathway and sugar signaling transduction pathways...
BACKGROUND
Salt is an important factor that affects crop productivity. Plant hexokinases (HXKs) are key enzymes in the glycolytic pathway and sugar signaling transduction pathways of plants. In previous studies, we identified and confirmed the roles of GmHXK2 in salt tolerance.
RESULTS
In this study, we analyzed the tissue-specific expression of GmHXK2 at different growth stages throughout the plant's life cycle. The results showed that GmHXK2 was expressed significantly in all tissues at vegetative stages, including germination and seedling. However, no expression was detected in the pods, and there was little expression in flowers during the later mature period. Arabidopsis plants overexpressing the GmHXK2 (OE) had more lateral roots. The OE seedlings also produced higher levels of auxin and ascorbic acid (AsA). Additionally, the expression levels of genes PMM, YUC4/YUC6/YUC8, and PIN/LAX1,LAX3, which are involved respectively in the synthesis of AsA and auxin, as well as polar auxin transport, were upregulated in OE plants. This upregulation occurred specifically under exogenous glucose treatment. AtHKT1, AtSOS1, and AtNHX1 were up-regulated in OE plants under salt stress, suggesting that GmHXK2 may modulate salt tolerance by maintaining ion balance within the cells and alleviating damage caused by salt stress. Additionally, we further confirmed the interaction between GmHXK2 and the protein GmPMM through yeast two-hybridization and bimolecular fluorescence complementation assays, respectively.
CONCLUSION
The expression of GmHXK2 gene in plants is organ-specific and developmental stage specific. GmHXK2 not only regulates the synthesis of AsA and the synthesis and distribution of auxin, but also promotes root elongation and induces lateral root formation, potentially enhancing soil water absorption. This study reveals the crosstalk between sugar signaling and hormone signaling in plants, where GmHXK2 acts as a glucose sensor through its interaction with GmPMM, and sheds light on the molecular mechanism by which GmHXK2 gene is involved in salt tolerance in plants.
Topics: Seedlings; Indoleacetic Acids; Salt Tolerance; Glycine max; Ascorbic Acid; Gene Expression Regulation, Plant; Plant Proteins; Arabidopsis; Plants, Genetically Modified
PubMed: 38937682
DOI: 10.1186/s12870-024-05301-3 -
Nature Materials Jun 2024Nanofluidic channels impose extreme confinement on water and ions, giving rise to unusual transport phenomena strongly dependent on the interactions at the channel-wall...
Nanofluidic channels impose extreme confinement on water and ions, giving rise to unusual transport phenomena strongly dependent on the interactions at the channel-wall interface. Yet how the electronic properties of the nanofluidic channels influence transport efficiency remains largely unexplored. Here we measure transport through the inner pores of sub-1 nm metallic and semiconducting carbon nanotube porins. We find that water and proton transport are enhanced in metallic nanotubes over semiconducting nanotubes, whereas ion transport is largely insensitive to the nanotube bandgap value. Molecular simulations using polarizable force fields highlight the contributions of the anisotropic polarizability tensor of the carbon nanotubes to the ion-nanotube interactions and the water friction coefficient. We also describe the origin of the proton transport enhancement in metallic nanotubes using deep neural network molecular dynamics simulations. These results emphasize the complex role of the electronic properties of nanofluidic channels in modulating transport under extreme nanoscale confinement.
PubMed: 38937586
DOI: 10.1038/s41563-024-01925-w -
Advanced Materials (Deerfield Beach,... Jun 2024Sodium-ion batteries (SIBs), recognized for balanced energy density and cost-effectiveness, are positioned as a promising complement to lithium-ion batteries (LIBs) and... (Review)
Review
Sodium-ion batteries (SIBs), recognized for balanced energy density and cost-effectiveness, are positioned as a promising complement to lithium-ion batteries (LIBs) and a substitute for lead-acid batteries, particularly in low-speed electric vehicles and large-scale energy storage. Despite their extensive potential, concerns about range anxiety due to lower energy density underscore the importance of fast-charging technologies, which drives the exploration of high-rate electrode materials. Polyanionic cathode materials are emerging as promising candidates in this regard. However, their intrinsic limitation in electronic conductivity poses challenges for synchronized electron and ion transport, hindering their suitability for fast-charging applications. This review provides a comprehensive analysis of sodium ion migration during charging/discharging, highlighting it as a critical rate-limiting step for fast charging. By delving into intrinsic dynamics, we identify and summarize key factors that constrain fast-charging characteristics. Innovative modification routes are then introduced, with a focus on shortening migration paths and increasing diffusion coefficients, providing detailed insights into feasible strategies. Moreover, the discussion extends beyond half cells to full cells, addressing challenges and opportunities in transitioning polyanionic materials from the laboratory to practical applications. This review aims to offer valuable insights into the development of high-rate polyanionic cathodes, acknowledging their pivotal role in advancing fast-charging SIBs. This article is protected by copyright. All rights reserved.
PubMed: 38936413
DOI: 10.1002/adma.202407359 -
Journal of Colloid and Interface Science Jun 2024Sluggish kinetics and severe structural instability of manganese-based cathode materials for rechargeable aqueous zinc-ion batteries (ZIBs) lead to low-rate capacity and...
Sluggish kinetics and severe structural instability of manganese-based cathode materials for rechargeable aqueous zinc-ion batteries (ZIBs) lead to low-rate capacity and poor cyclability, which hinder their practical applications. Pillaring manganese dioxide (MnO) by pre-intercalation is an effective strategy to solve the above problems. However, increasing the pre-intercalation content to realize stable cycling of high capacity at large current densities is still challenging. Here, high-rate aqueous Zn storage is realized by a high-capacity K-pillared multi-nanochannel MnO cathode with 1 K per 4 Mn (δ-KMnO). The high content of the K pillar, in conjunction with the three-dimensional confinement effect and size effect, promotes the stability and electron transport of multi-nanochannel layered MnO in the ion insertion/removal process during cycling, accelerating and accommodating more Zn diffusion. Multi-perspective in/ex-situ characterizations conclude that the energy storage mechanism is the Zn/H ions co-intercalating and phase transformation process. More specifically, the δ-KMnO nanospheres cathode delivers an ultrahigh reversible capacity of 297 mAh g at 1 A g for 500 cycles, showing over 96 % utilization of the theoretical capacity of δ-MnO. Even at 3 A g, it also delivered a 63 % utilization and 64 % capacity retention after 1000 cycles. This study introduces a highly efficient cathode material based on manganese oxide and a comprehensive analysis of its structural dynamics. These findings have the potential to improve energy storage capabilities in ZIBs significantly.
PubMed: 38936090
DOI: 10.1016/j.jcis.2024.06.170 -
Journal of Colloid and Interface Science Jun 2024Polypyrrole-coated CuInS (CuInS@PPy) composite was prepared through the chemical vapor transport method and subsequent in situ polymerized coating strategy. In this...
Polypyrrole-coated CuInS (CuInS@PPy) composite was prepared through the chemical vapor transport method and subsequent in situ polymerized coating strategy. In this unique nanoarchitecture, the PPy coating layer plays a crucial role in improving the conductivity of the composite, suppressing the volume change of CuInS, and maintaining the structural integrity of electrode material upon cycling. In addition, the electrochemical reaction mechanism and kinetics of CuInS@PPy were investigated in-depth. Benefitting from the synergism of its combinational intercalation-conversion-intercalation reaction mechanism and the high conductivity of the PPy coating layer, CuInS@PPy electrode exhibits superior rate capability and cycling stability for sodium-ion batteries, with a capacity of 404.8 mA h g at 4 A g over 2500 cycles.
PubMed: 38936081
DOI: 10.1016/j.jcis.2024.06.163