Because of their remarkable properties,room-temperature ionic liquids(RTILs)are used widely in electrochemistry,fuel cells,supercapacitors,and even DNA sequencing,and many of these applications involve the transport o...Because of their remarkable properties,room-temperature ionic liquids(RTILs)are used widely in electrochemistry,fuel cells,supercapacitors,and even DNA sequencing,and many of these applications involve the transport of RTILs in nanoscale media.Particularly for single-molecule detection,the RTIL must be mixed with a solvent(e.g.,water)so that the electrolyte has both high viscosity and conductivity to obtain excellent signals.If a RTIL contains a quantity of water in bulk,this has a significant effect on its properties(e.g.,the electrochemical window),thereby limiting some applications.However,the physicochemical properties of RTILs containing water in nanoconfined spaces remain unclear,especially their ionic transport behavior.Therefore,reported here is a study of the ionic transport behavior of mixed RTIL/water solutions at the nanoscale using a single conical nanochannel as a nanofluidic platform.The conductivity of the mixtures in the nanoconfined space was closely related to the nanochannel size,and highly diluted mixed solutions resulted in a nonlinear rectificationreversed current,which was possibly due to the adsorption of cations on the nanochannel wall.The maximum rectification ratio was 114,showing excellent rectification that could be used to realize newly conceptualized nanofluidic diodes.In summary,this work provides an exhaustive understanding of the nonlinear ion transport of RTIL/water mixtures and a theoretical foundation for applying RTILs in energy storage and conversion and bio-sensing.展开更多
Negatively thermo-responsive 2D membranes,which mimic the stomatal opening/closing of plants,have drawn substantial interest for tunable molecular separation processes.However,these membranes are still restricted sign...Negatively thermo-responsive 2D membranes,which mimic the stomatal opening/closing of plants,have drawn substantial interest for tunable molecular separation processes.However,these membranes are still restricted significantly on account of low water permeability and poor dynamic tunability of 2D nanochannels under temperature stimulation.Here,we present a biomimetic negatively thermo-responsive MXene membrane by covalently grafting poly(N-isopropylacrylamide)(PNIPAm)onto MXene nanosheets.The uniformly grafted PNIPAm polymer chains can enlarge the interlayer spacings for increasing water permeability while also allowing more tunability of 2D nanochannels for enhancing the capability of gradually separating multiple molecules of different sizes.As expected,the constructed membrane exhibits ultrahigh water permeance of 95.6 L m^(-2) h^(-1) bar^(-1) at 25℃,which is eight-fold higher than the state-of-the-art negatively thermoresponsive 2D membranes.Moreover,the highly temperature-tunable 2D nanochannels enable the constructed membrane to perform excellent graded molecular sieving for dye-and antibiotic-based ternary mixtures.This strategy provides new perspectives in engineering smart 2D membrane and expands the scope of temperature-responsive membranes,showing promising applications in micro/nanofluidics and molecular separation.展开更多
Strontium-90,a highly radioactive isotope,accumulates within the food chain and skeletal structure,posing significant risks to human health.There is a critical need for a sensitive detection strategy for Strontium-90 ...Strontium-90,a highly radioactive isotope,accumulates within the food chain and skeletal structure,posing significant risks to human health.There is a critical need for a sensitive detection strategy for Strontium-90 in complex environmental samples.Here,solid-state nanochannels,modified with metal-organic frameworks(MOF)and specific aptamers,were engineered for highly sensitive detection of strontium ion(Sr^(2+)).The synergistic effect between the reduced effective diameter of the nanochannels due to MOF and the specific binding of Sr^(2+) by aptamers amplifies the difference in ionic current signals,enhancing detection sensitivity significantly.The MOF-modified nanochannels exhibit highly sensitive detection of Sr^(2+),with a limit of detection(LOD)being 0.03 nmol·L^(-1),whereas the LOD for anodized aluminum oxide(AAO)without the modified MOF nanosheets is only 1000 nmol·L^(-1).These findings indicate that the LOD of Sr^(2+) detected by the MOF-modified nanochannels is approximately 33,000 times higher than that by the nanochannels without MOF modification.Additionally,the highly reliable detection of Sr^(2+) in various water samples was achieved,with a recovery rate ranging from 94.00%to 118.70%.This study provides valuable insights into the rapidly advancing field of advanced nanochannel-based sensors and their diverse applications for analyzing complex samples,including environmental contaminant detection,food analysis,medical diagnostics,and more.展开更多
With the development of nanotechnology and materials science,bioinspired nanochannels appeared by mimicking the intelligent functions of biological ion channels.They have attracted a great deal of at-tention in recent...With the development of nanotechnology and materials science,bioinspired nanochannels appeared by mimicking the intelligent functions of biological ion channels.They have attracted a great deal of at-tention in recent years due to their controllable structure and tunable chemical properties.Inspired by the layered microstructure of nacre,2D layered materials as excellent matrix material of nanochannel come into our field of vision.Bionic nanochannels based on 2D materials have the advantages of facile preparation,tunable channel size and length,easy expansion,and modification,etc.Therefore,the 2D layered nanofluid system based on bionic nanochannels from 2D layered materials has great potential in biomimetic microsensors,membrane separations,energy conversion,and so on.In this paper,we focus on the construction and application of bionic nanochannels based on 2D layer materials.First,a basic understanding of nanochannels based on 2D materials is briefly introduced,we also present the property of the 2D materials and construction strategies of bionic nanochannels.Subsequently,the application of these nanochannels in responsive channels and energy conversion is discussed.The unsolved challenges and prospects of 2D materials-based nanochannels are proposed in the end.展开更多
The model of ion transportation through graphene nanochannels is established by the molecular dynamics simulation method. Statistics of the electric potential and charge distribution are made, respectively, on both si...The model of ion transportation through graphene nanochannels is established by the molecular dynamics simulation method. Statistics of the electric potential and charge distribution are made, respectively, on both sides of graphene nanopore with various diameters. Then, their changing relationship with respect to the nanopore diameter is determined. When applying a uniform electric field, polar water molecules are rearranged so that the corresponding relationship between the polarized degree of these molecules and the nanopore diameter can be created. Based on the theoretical model of ion transportation through nanochannels,the changing relationship between the concentration of anions/cations in nanochannels and bulk solution concentration is quantitatively analyzed. The results show that the increase of potential drop and charge accumulation, as well as a more obvious water polarization, will occur with the decrease of nanopore diameter. In addition, hydrogen ion concentration has a large proportion in nanochannels with a sodium chloride（NaCl） solution at a relative low concentration. As the NaCl concentration increases, the concentration appreciation of sodium ions tends to be far greater than the concentration drop of chloride ions. Therefore, sodium ion concentration makes more contribution to ionic conductance.展开更多
The construction of nanostructured ion-transport channels is highly desirable in the design of advanced electrolyte materials,as it can enhance ion conductivity by offering short ion-transport pathways.In this work,we...The construction of nanostructured ion-transport channels is highly desirable in the design of advanced electrolyte materials,as it can enhance ion conductivity by offering short ion-transport pathways.In this work,we present a supramolecular strategy to fabricate a nanocomposite electrolyte containing highly ordered lamellar proton-conducting nanochannels,by the electrostatic self-assembly of a polyoxometalate H_(3)PW1_(2)O_(4)O(PW)and a comb copolymer poly(4-methlstyrene)-graft-poly(N-vinyl pyrrolidone).PW can effectively regulate the self-assembling order of polymer moieties to form a large-ra nge lamellar structure,meanwhile,introducing protons into the nanoscale lamellar domains to build proton transport channels.Moreover,the rigid PW clusters contribute a remarkable mechanical reinforcement to the nanocomposites.The lamellar nanocomposite exhibits a conductivity of 4.3×10^(-4)S/cm and a storage modulus of 1.1×10^(7)Pa at room temperature.This study provides a new strategy to construct nanostructured ion-conductive pathways in electrolyte materials.展开更多
A novel mixed barium(II)/silver(I)/chromium(III) oxalate salt, Ba<sub>0.5</sub>Ag<sub>2</sub>[Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·5H<sub>2...A novel mixed barium(II)/silver(I)/chromium(III) oxalate salt, Ba<sub>0.5</sub>Ag<sub>2</sub>[Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·5H<sub>2</sub>O (1), with open architecture has been synthesized in water and characterized by elemental analysis, vibrational and electronic spectra, and single crystal X-ray structure determination. Compound 1 crystallizes in a monoclinic space group C2/c, with unit cell parameters a = 18.179(3), b = 14.743(2), c = 12.278(2)Å, β = 113.821(3), V = 3010.34(90) Å<sup>3</sup>, Z = 8. The structure is characterized by a network of anionic [Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]<sup>3-</sup> units connected through the O atoms of the oxalates to Ba<sup>2+</sup> and Ag<sup>+</sup> sites, forming a three-dimensional coordination polymer with one-dimensional isolated nanochannels parallel to the c axis, and encapsulating hydrogen-bonded vip water molecules. The bulk structure is consolidated by O–H···O bridgings within the nanochannels and by coulombic interactions.展开更多
.Nanochannel structures with a feature size deeply under the diffraction limit and a high aspect ratio hold huge biomedical significance,which is especially challenging to be realized on hard and brittle materials,suc....Nanochannel structures with a feature size deeply under the diffraction limit and a high aspect ratio hold huge biomedical significance,which is especially challenging to be realized on hard and brittle materials,such as silica,diamond,and sapphire.By simultaneously depositing the pulse energy on the surface and inside the sample,nanochannels with the smallest feature size of 18 nm(∼1∕30λ)and more than 200 aspect ratios are achieved inside silica,the mechanism of which can be concluded as the surface assisting material ejection effect.Both the experimental and theoretical results prove that the coaction of the superficial“hot domain”and internal hot domain dominates the generation of the nanochannels,which gives new insights into the laser-material interacting mechanisms and potentially promotes the corresponding application fields.展开更多
The atomic behavior of liquid-solid mixed-phase nanofluid flows inside nanochannels is investigated by a molecular dynamics simulation （MDS）. The results of visual observation and statistic analysis show that when t...The atomic behavior of liquid-solid mixed-phase nanofluid flows inside nanochannels is investigated by a molecular dynamics simulation （MDS）. The results of visual observation and statistic analysis show that when the nanoparticles reach near each other, the strong interatomic force will make them attach together. This aggrega- tion continues until all nanoparticles make a continuous cluster. The effect of altering the external force magnitude causes changes in the agglomeration rate and system enthalpy. The density and velocity profiles are shown for two systems, i.e., argon （Ar）-copper （Cu） nanofluid and simple Ar fluid between two Cu walls. The results show that using nanopar- ticles changes the base fluid particles ordering along the nanochannel and increases the velocity. Moreover, using nanoparticles in simple fluids can increase the slip length and push the near-wall fluid particles into the main flow in the middle of the nanochannel.展开更多
CONSPECTUS:After billions of years of evolution,organisms in nature have almost completed the intelligent manipulation of all life processes.Biological nanopores embedded in the cell membrane of organisms are represen...CONSPECTUS:After billions of years of evolution,organisms in nature have almost completed the intelligent manipulation of all life processes.Biological nanopores embedded in the cell membrane of organisms are representatives with intelligent manipulation capabilities.Biological nanopores can achieve controllable transmembrane transport of various ions and molecules,playing an important role in molecular biology processes such as substance exchange,signal transmission,energy conversion,and system function regulation in cells.Scientists have utilized biological nanopores for sensing analysis,such as gene sequencing and single-molecule detection.However,due to the characteristic that proteins(components of biological nanopores)cannot exist stably for a long time,scientists have developed solid-state nanopores/nanochannels with high mechanical strength,strong plasticity,and easy surface modification.展开更多
Gating,a fundamental feature of biological nanochannels,enables the intelligent regulation of ion and molecule transport in response to specific requirements.Inspired by nature,numerous artificial gating systems have ...Gating,a fundamental feature of biological nanochannels,enables the intelligent regulation of ion and molecule transport in response to specific requirements.Inspired by nature,numerous artificial gating systems have been researched through the functionalization of solid-state nanochannels.However,these gating systems typically allow only two transitions:“open”and“closed”,which makes it challenging to achieve multi-state transport.Herein,we construct dynamic liquid film nanochannels(DLFNs)by inserting an oil droplet into a capillary with gradient wettability that is filled with ionic solutions.The liquid film,formed between the oil and the capillary,functions as a nanochannel for ion and molecule transport,with its height dynamically adjusted through the capillary's gradient wettability.At a deeper level,the variations in liquid film thickness are driven by the interfacial water structure,which is mediated by hydrogen bonding interactions.Furthermore,unlike traditional solid-state nanochannels,which involve two phases(liquid/solid),the properties of DLFNs are influenced by three phases(oil/water/solid),resulting in distinct performance characteristics,such as reconfigurability,low cost,and ease of fabrication.This work provides an avenue for designing dynamic nanofluids and may spark promising applications of DLFNs with multiscale gating properties in drug delivery,microreactors,sieving,biosensing,and other related fields.展开更多
Glass-based nanochannels have become powerful tools for chemi-cal and biological sensing due to their advantages of easy prepara-tion,flexible modification,and high sensitivity.Lately,research on ion transport behavio...Glass-based nanochannels have become powerful tools for chemi-cal and biological sensing due to their advantages of easy prepara-tion,flexible modification,and high sensitivity.Lately,research on ion transport behaviors in glass-based nanochannels and their applications in nanofluidic iontronics has gradually become a focus,including various ion transport behaviors such as resistive-pulse,ion rectification,ionic current memory,etc.In this review,we summarize the progress of manufacturing methods for glass-based nanochannels and discuss several typical ion transport behaviors of glass-based nanochannels,as well as the main application scenarios of glass-based nanochannels in terms of biosensing,detection,and neuromorphic functions.The enormous assistance of artificial intel-ligence in the standardized manufacturing process of glass-based nanochannels was anticipated,and the potential development of glass-based nanochannels in achieving neuromorphic functions was expected.展开更多
Membrane fouling inevitably occurs during nanofluidic reverse electrodialysis.Herein,the impact of multi-fouling on the energy conversion performance of negatively charged conical nanochannels under asymmetrical confi...Membrane fouling inevitably occurs during nanofluidic reverse electrodialysis.Herein,the impact of multi-fouling on the energy conversion performance of negatively charged conical nanochannels under asymmetrical configurations is systematically investigated.The results reveal that in Configuration I,where a high-concentration solution is applied at the tip side,at small concentration ratios,multiple foulings reduce the electric power.In Configuration II,where a low-concentration solution is applied at the tip side,multiple foulings near the base side contribute to the electric power.Any fouling that formed near the lowconcentration entrance diminished the electric power and energy conversion efficiency.Multi-fouling lowered the electrical power consumption by 69.27%and 99.94%in Configurations I and II,respectively.In Configuration I,the electric power first increased with increasing fouling surface charge density,reached its maximum value,and thereafter decreased.In Configuration II,the electric power first decreased with increasing fouling surface charge density,reached its minimum value,and thereafter increased.Large negative or positive charge densities of fouling contribute to the electric power and energy conversion efficiency.展开更多
Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major ch...Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators.展开更多
Cr coatings,as protective coatings of Zr-alloy fuel claddings,inevitably suffer from irradiation damage before they would possibly run into the accident condition.This study evaluates the radiation and oxidation toler...Cr coatings,as protective coatings of Zr-alloy fuel claddings,inevitably suffer from irradiation damage before they would possibly run into the accident condition.This study evaluates the radiation and oxidation tolerance of three Cr-based coatings with different microstructures(Cr,CrAlSi,and CrAlSiN)through He2+ion irradiation and 1200℃ steam oxidation.The Cr and CrAlSi coatings experienced significant structural degradation,characterized by He bubble aggregation and amplified Kirkendall effects at elevated temperatures.In contrast,the irradiated CrAlSiN coating maintained structural integrity without measurable irradiation hardening.Following annealing at 800℃ for 30 min,approximately 40%of injected He atoms were released,indicating a“self-healing”mechanism.The mechanism is attributed to uniformly distributed,low-density channels that act as sinks and release paths for irradiation-induced defects.Density functional theory simulations suggest that N atoms promote significant rearrangement of ions surrounding the free volume,inhibiting the formation of sites capable of trapping He atoms.Moreover,the CrAlSiN coating exhibited superior oxidation resistance compared to the Cr and CrAlSi coatings,even under high-temperature steam conditions.Notably,the irradiated CrAlSiN sample displayed a significantly thinner oxide scale compared to the pristine one(almost half),owing to a more protective oxide scale and rapid outward diffusion of Cr,Al,and Si through nanochannel veins.These findings illuminate the effects of structure and composition on irradiation and oxidation behavior in Cr-based coatings,offering insights for developing new-generation accident-tolerance fuel coatings for Zr-alloy claddings.展开更多
Cancers and chronic diseases have always been global health problems. The occurrence and development of such diseases are closely related to the abnormalities of proteins, nucleic acids, ions or small molecules in the...Cancers and chronic diseases have always been global health problems. The occurrence and development of such diseases are closely related to the abnormalities of proteins, nucleic acids, ions or small molecules in the body. Nowadays, nanopores/nanochannels have emerged as a powerful platform for detecting these biomolecules based on the electrical signal variation caused by biomolecules passing. However, detection relied on the electrical signal easily suffered from the clogging defects, low throughput, and strong background signals. Fortunately, the emergence of designing nanopores/nanochannels based on electrical and optical dual signal response has brought innovative impetus to biological detection, which can also identify the chemical compositions and conformations of the biomolecules. In this review, we summarize the reasonable preparation of nanopores/nanochannels with electrical and optical dual signal response and their application in biological detection. According to different biomolecules, we divide the targets into four types, including nucleic acids, small molecules, ions and proteins. In each section, the design of representative examples and the principle of dual signal generation are introduced and discussed. Finally, the prospects and challenges of nanopores/nanochannels based on electrical and optical dual signal response are also discussed.展开更多
Metal organic framework(MOF)incorporated thin-film nanocomposite(TFN)membranes have the potential to enhance the removal of endocrine disrupting compounds(EDCs).In MOF-TFN membranes,water transport nanochannels includ...Metal organic framework(MOF)incorporated thin-film nanocomposite(TFN)membranes have the potential to enhance the removal of endocrine disrupting compounds(EDCs).In MOF-TFN membranes,water transport nanochannels include(i)pores of polyamide layer,(ii)pores in MOFs and(iii)channels around MOFs(polyamide-MOF interface).However,information on how to tune the nanochannels to enhance EDCs rejection is scarce,impeding the refinement of TFN membranes toward efficient removal of EDCs.In this study,by changing the polyamide properties,the water transport nanochannels could be confined primarily in pores of MOFs when the polyamide layer became dense.Interestingly,the improved rejection of EDCs was dependent on the water transport channels of the TFN membrane.At low monomer concentration(i.e.,loose polyamide structure),the hydrophilic nanochannels of MIL-101(Cr)in the polyamide layer could not dominate the membrane separation performance,and hence the extent of improvement in EDCs rejection was relatively low.In contrast,at high monomer concentration(i.e.,dense polyamide structure),the hydrophilic nanochannels of MIL-101(Cr)were responsible for the selective removal of hydrophobic EDCs,demonstrating that the manipulation of water transport nanochannels in the TFN membrane could successfully overcome the permeability and EDCs rejection trade-off.Our results highlight the potential of tuning primary selective nanochannels of MOF-TFN membranes for the efficient removal of EDCs.展开更多
Nanochannel technology based on ionic current rectification has emerged as a powerful tool for the detection of biomolecules owing to unique advantages.Nevertheless,existing nanochannel sensors mainly focus on the det...Nanochannel technology based on ionic current rectification has emerged as a powerful tool for the detection of biomolecules owing to unique advantages.Nevertheless,existing nanochannel sensors mainly focus on the detection of targets in solution or inside the cells,moreover,they only have a single function,greatly limiting their application.Herein,we fabricated SuperDNA self-assembled conical nanochannel,which was clamped in the middle of self-made device for two functions:Online detecting living cells released TNF-αand studying intercellular communication.Polyethylene terephthalate(PET)membrane incubated tumor associated macrophages and tumor cells was rolled up and inserted into the left and right chamber of the device,respectively.Through monitoring the ion current change in the nanochannel,tumor associated macrophages released TNF-αcould be in situ and noninvasive detected with a detection limit of 0.23 pg/mL.Furthermore,the secreted TNF-αinduced epithelial-mesenchymal transformation of tumor cells in the right chamber was also studied.The presented strategy displayed outstanding performance and multi-function,providing a promising platform for in situ non-destructive detection of cell secretions and related intercellular communication analysis.展开更多
A systematic understanding of the mechanism in the rectification and capacitance of nanochannels and their regulation with the electrolyte concentration and electrical bias is pivotal for its wide applications to nano...A systematic understanding of the mechanism in the rectification and capacitance of nanochannels and their regulation with the electrolyte concentration and electrical bias is pivotal for its wide applications to nanofluidic electronics,ion separation,energy storage,and molecule sensing.Single unipolar and bipolar cylindrical nanochannels through polymer film were fabricated using single ion bombardment and track etching.Cyclic voltammetry results show that the bipolar nanochannel switches from rectification to capacitance as the electrolyte concentration decreases.Electrochemical impedance spectroscopy revealed that the capacitive impedance fraction in the bipolar nanochannel is regulated by electrolyte concentration and voltage.The switch from rectification to capacitance in the polymer nanochannel is well explained through a fluidic p-n junction model with a variable ion depletion layer regulated by the applied bias voltage,which is supported by the multi-physics simulation using Poisson-Nernst-Planck and Navier-Stokes solution.This work provides a mechanistic insight into the ionic current rectification and ionic capacitance in complex ionic nanochannels and paves the way for biomimetic nanofluidic electronics design.展开更多
Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extrac...Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy fromthe salinity gradient energy.However,the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance,especially the trade-offs between ion selectivity and mass transfer in nanochannels,of NRED poses a great challenge to achieving breakthroughs in energy conversion processes.This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors,including the nanochannel configuration,the temperature field,and the concentration difference,on the energy conversion processes of NRED.In this work,a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications,thereby enhancing the realism and applicability of our analysis.Numerical results reveal that the application of a temperature gradient,which is oriented in opposition to the concentration gradient,enhances the ion transportation and selectivity simultaneously,leading to an enhancement in both output power and energy conversion efficiency.Additionally,the increased fluctuation of the nanochannel wall from s=0 to s=0.08 improves ion selectivity yet raises ion transport resistance,resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current.Furthermore,with increasing the concentration ratio cH/cL from 10 to 1000,either within a fixed temperature field or at a constant dimensionless amplitude,the maximumpower consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences amonotonic decrease across this entire range of concentration ratios.Finally,uponmodifying the operational parameters fromthe baseline condition of s=0,c_(H)/c_(L)=10,andΔT=0 K to the targetedconditionof s=0.08,c_(H)/c_(L)=50,andΔT=25 K,there is a concerted improvement observed in the open-circuit potential,short-circuit current,andmaximumpower,with respective increments of 8.86%,204.97%,and 232.01%,but a reduction in cation transfer number with a notable decrease of 15.37%.展开更多
基金supported by the Guangdong high level Innovation Research Institute(Grant No.2021B0909050006).
文摘Because of their remarkable properties,room-temperature ionic liquids(RTILs)are used widely in electrochemistry,fuel cells,supercapacitors,and even DNA sequencing,and many of these applications involve the transport of RTILs in nanoscale media.Particularly for single-molecule detection,the RTIL must be mixed with a solvent(e.g.,water)so that the electrolyte has both high viscosity and conductivity to obtain excellent signals.If a RTIL contains a quantity of water in bulk,this has a significant effect on its properties(e.g.,the electrochemical window),thereby limiting some applications.However,the physicochemical properties of RTILs containing water in nanoconfined spaces remain unclear,especially their ionic transport behavior.Therefore,reported here is a study of the ionic transport behavior of mixed RTIL/water solutions at the nanoscale using a single conical nanochannel as a nanofluidic platform.The conductivity of the mixtures in the nanoconfined space was closely related to the nanochannel size,and highly diluted mixed solutions resulted in a nonlinear rectificationreversed current,which was possibly due to the adsorption of cations on the nanochannel wall.The maximum rectification ratio was 114,showing excellent rectification that could be used to realize newly conceptualized nanofluidic diodes.In summary,this work provides an exhaustive understanding of the nonlinear ion transport of RTIL/water mixtures and a theoretical foundation for applying RTILs in energy storage and conversion and bio-sensing.
基金supported by the National Nature Science Foundation of China(No.22278179,U23A20688)the National Key Research and Development Program of China(2021YFB3802600)+3 种基金the Fundamental Research Funds for the Central Universities(JUSRP622035)National First-Class Discipline Program of Light Industry Technology and Engineering(LIFE2018-19)MOE&SAFEA for the 111 Project(B13025)Natural Science Foundation of Xinjiang Uygur Autonomous Region(2022D01D030).
文摘Negatively thermo-responsive 2D membranes,which mimic the stomatal opening/closing of plants,have drawn substantial interest for tunable molecular separation processes.However,these membranes are still restricted significantly on account of low water permeability and poor dynamic tunability of 2D nanochannels under temperature stimulation.Here,we present a biomimetic negatively thermo-responsive MXene membrane by covalently grafting poly(N-isopropylacrylamide)(PNIPAm)onto MXene nanosheets.The uniformly grafted PNIPAm polymer chains can enlarge the interlayer spacings for increasing water permeability while also allowing more tunability of 2D nanochannels for enhancing the capability of gradually separating multiple molecules of different sizes.As expected,the constructed membrane exhibits ultrahigh water permeance of 95.6 L m^(-2) h^(-1) bar^(-1) at 25℃,which is eight-fold higher than the state-of-the-art negatively thermoresponsive 2D membranes.Moreover,the highly temperature-tunable 2D nanochannels enable the constructed membrane to perform excellent graded molecular sieving for dye-and antibiotic-based ternary mixtures.This strategy provides new perspectives in engineering smart 2D membrane and expands the scope of temperature-responsive membranes,showing promising applications in micro/nanofluidics and molecular separation.
基金supported by the National Natural Science Foundation of China(No.22090050,No.22090052,No.22176180)National Basic Research Program of China(No.2021YFA1200400)+1 种基金the Natural Science Foundation of Hubei Province(No.2024AFA001)Shenzhen Science and Technology Program(No.JCYJ20220530162406014)。
文摘Strontium-90,a highly radioactive isotope,accumulates within the food chain and skeletal structure,posing significant risks to human health.There is a critical need for a sensitive detection strategy for Strontium-90 in complex environmental samples.Here,solid-state nanochannels,modified with metal-organic frameworks(MOF)and specific aptamers,were engineered for highly sensitive detection of strontium ion(Sr^(2+)).The synergistic effect between the reduced effective diameter of the nanochannels due to MOF and the specific binding of Sr^(2+) by aptamers amplifies the difference in ionic current signals,enhancing detection sensitivity significantly.The MOF-modified nanochannels exhibit highly sensitive detection of Sr^(2+),with a limit of detection(LOD)being 0.03 nmol·L^(-1),whereas the LOD for anodized aluminum oxide(AAO)without the modified MOF nanosheets is only 1000 nmol·L^(-1).These findings indicate that the LOD of Sr^(2+) detected by the MOF-modified nanochannels is approximately 33,000 times higher than that by the nanochannels without MOF modification.Additionally,the highly reliable detection of Sr^(2+) in various water samples was achieved,with a recovery rate ranging from 94.00%to 118.70%.This study provides valuable insights into the rapidly advancing field of advanced nanochannel-based sensors and their diverse applications for analyzing complex samples,including environmental contaminant detection,food analysis,medical diagnostics,and more.
基金supported by the National Natural Science Foundation of China (No. 22005162)the Natural Science Foundation of Shandong Province (No. ZR2020QE093)+1 种基金the China Postdoctoral Science Foundation (No. 2019M652319)the Special Financial Aid to Post-doctor Research Fellow (No. 2020T130330)
文摘With the development of nanotechnology and materials science,bioinspired nanochannels appeared by mimicking the intelligent functions of biological ion channels.They have attracted a great deal of at-tention in recent years due to their controllable structure and tunable chemical properties.Inspired by the layered microstructure of nacre,2D layered materials as excellent matrix material of nanochannel come into our field of vision.Bionic nanochannels based on 2D materials have the advantages of facile preparation,tunable channel size and length,easy expansion,and modification,etc.Therefore,the 2D layered nanofluid system based on bionic nanochannels from 2D layered materials has great potential in biomimetic microsensors,membrane separations,energy conversion,and so on.In this paper,we focus on the construction and application of bionic nanochannels based on 2D layer materials.First,a basic understanding of nanochannels based on 2D materials is briefly introduced,we also present the property of the 2D materials and construction strategies of bionic nanochannels.Subsequently,the application of these nanochannels in responsive channels and energy conversion is discussed.The unsolved challenges and prospects of 2D materials-based nanochannels are proposed in the end.
基金The National Basic Research Program of China(973Program)(No.2011CB707600)the National Natural Science Founda tion of China(No.51435003,51375092)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20160935)the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(No.16KJB460015)
文摘The model of ion transportation through graphene nanochannels is established by the molecular dynamics simulation method. Statistics of the electric potential and charge distribution are made, respectively, on both sides of graphene nanopore with various diameters. Then, their changing relationship with respect to the nanopore diameter is determined. When applying a uniform electric field, polar water molecules are rearranged so that the corresponding relationship between the polarized degree of these molecules and the nanopore diameter can be created. Based on the theoretical model of ion transportation through nanochannels,the changing relationship between the concentration of anions/cations in nanochannels and bulk solution concentration is quantitatively analyzed. The results show that the increase of potential drop and charge accumulation, as well as a more obvious water polarization, will occur with the decrease of nanopore diameter. In addition, hydrogen ion concentration has a large proportion in nanochannels with a sodium chloride（NaCl） solution at a relative low concentration. As the NaCl concentration increases, the concentration appreciation of sodium ions tends to be far greater than the concentration drop of chloride ions. Therefore, sodium ion concentration makes more contribution to ionic conductance.
基金supported by the National Natural Science Foundation of China(No.22075097)the Program for JLU Science and Technology Innovative Research Team(No.2017TD-10)the Open Research Fund of State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences(No.2020-09)。
文摘The construction of nanostructured ion-transport channels is highly desirable in the design of advanced electrolyte materials,as it can enhance ion conductivity by offering short ion-transport pathways.In this work,we present a supramolecular strategy to fabricate a nanocomposite electrolyte containing highly ordered lamellar proton-conducting nanochannels,by the electrostatic self-assembly of a polyoxometalate H_(3)PW1_(2)O_(4)O(PW)and a comb copolymer poly(4-methlstyrene)-graft-poly(N-vinyl pyrrolidone).PW can effectively regulate the self-assembling order of polymer moieties to form a large-ra nge lamellar structure,meanwhile,introducing protons into the nanoscale lamellar domains to build proton transport channels.Moreover,the rigid PW clusters contribute a remarkable mechanical reinforcement to the nanocomposites.The lamellar nanocomposite exhibits a conductivity of 4.3×10^(-4)S/cm and a storage modulus of 1.1×10^(7)Pa at room temperature.This study provides a new strategy to construct nanostructured ion-conductive pathways in electrolyte materials.
文摘A novel mixed barium(II)/silver(I)/chromium(III) oxalate salt, Ba<sub>0.5</sub>Ag<sub>2</sub>[Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·5H<sub>2</sub>O (1), with open architecture has been synthesized in water and characterized by elemental analysis, vibrational and electronic spectra, and single crystal X-ray structure determination. Compound 1 crystallizes in a monoclinic space group C2/c, with unit cell parameters a = 18.179(3), b = 14.743(2), c = 12.278(2)Å, β = 113.821(3), V = 3010.34(90) Å<sup>3</sup>, Z = 8. The structure is characterized by a network of anionic [Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]<sup>3-</sup> units connected through the O atoms of the oxalates to Ba<sup>2+</sup> and Ag<sup>+</sup> sites, forming a three-dimensional coordination polymer with one-dimensional isolated nanochannels parallel to the c axis, and encapsulating hydrogen-bonded vip water molecules. The bulk structure is consolidated by O–H···O bridgings within the nanochannels and by coulombic interactions.
基金supported by the National Natural Science Foundation of China under Grant Nos.12127806,62175195,and 61875158the International Joint Research Laboratory for Micro/Nano Manufacturing and Measurement Technologies,and the Fundamental Research Funds for the Central Universities.
文摘.Nanochannel structures with a feature size deeply under the diffraction limit and a high aspect ratio hold huge biomedical significance,which is especially challenging to be realized on hard and brittle materials,such as silica,diamond,and sapphire.By simultaneously depositing the pulse energy on the surface and inside the sample,nanochannels with the smallest feature size of 18 nm(∼1∕30λ)and more than 200 aspect ratios are achieved inside silica,the mechanism of which can be concluded as the surface assisting material ejection effect.Both the experimental and theoretical results prove that the coaction of the superficial“hot domain”and internal hot domain dominates the generation of the nanochannels,which gives new insights into the laser-material interacting mechanisms and potentially promotes the corresponding application fields.
文摘The atomic behavior of liquid-solid mixed-phase nanofluid flows inside nanochannels is investigated by a molecular dynamics simulation （MDS）. The results of visual observation and statistic analysis show that when the nanoparticles reach near each other, the strong interatomic force will make them attach together. This aggrega- tion continues until all nanoparticles make a continuous cluster. The effect of altering the external force magnitude causes changes in the agglomeration rate and system enthalpy. The density and velocity profiles are shown for two systems, i.e., argon （Ar）-copper （Cu） nanofluid and simple Ar fluid between two Cu walls. The results show that using nanopar- ticles changes the base fluid particles ordering along the nanochannel and increases the velocity. Moreover, using nanoparticles in simple fluids can increase the slip length and push the near-wall fluid particles into the main flow in the middle of the nanochannel.
基金supported by the National Natural Science Foundation of China(22474132,22090050)National Key R&D Program of China(2021YFA1200403)Joint NSFCISF Research Grant Program(22161142020).
文摘CONSPECTUS:After billions of years of evolution,organisms in nature have almost completed the intelligent manipulation of all life processes.Biological nanopores embedded in the cell membrane of organisms are representatives with intelligent manipulation capabilities.Biological nanopores can achieve controllable transmembrane transport of various ions and molecules,playing an important role in molecular biology processes such as substance exchange,signal transmission,energy conversion,and system function regulation in cells.Scientists have utilized biological nanopores for sensing analysis,such as gene sequencing and single-molecule detection.However,due to the characteristic that proteins(components of biological nanopores)cannot exist stably for a long time,scientists have developed solid-state nanopores/nanochannels with high mechanical strength,strong plasticity,and easy surface modification.
基金supported by the National Natural Science Foundation of China(No.22090052)Frontier Science Key Projects of CAS(No.ZDBS-LY-SLH022)+1 种基金Key R&D Project of Shandong Province(No.2022CXGC010302)Xiaomi Young Talents Program.
文摘Gating,a fundamental feature of biological nanochannels,enables the intelligent regulation of ion and molecule transport in response to specific requirements.Inspired by nature,numerous artificial gating systems have been researched through the functionalization of solid-state nanochannels.However,these gating systems typically allow only two transitions:“open”and“closed”,which makes it challenging to achieve multi-state transport.Herein,we construct dynamic liquid film nanochannels(DLFNs)by inserting an oil droplet into a capillary with gradient wettability that is filled with ionic solutions.The liquid film,formed between the oil and the capillary,functions as a nanochannel for ion and molecule transport,with its height dynamically adjusted through the capillary's gradient wettability.At a deeper level,the variations in liquid film thickness are driven by the interfacial water structure,which is mediated by hydrogen bonding interactions.Furthermore,unlike traditional solid-state nanochannels,which involve two phases(liquid/solid),the properties of DLFNs are influenced by three phases(oil/water/solid),resulting in distinct performance characteristics,such as reconfigurability,low cost,and ease of fabrication.This work provides an avenue for designing dynamic nanofluids and may spark promising applications of DLFNs with multiscale gating properties in drug delivery,microreactors,sieving,biosensing,and other related fields.
基金supported by the National Natural Science Foundation of China(Nos.52303380,21975209,52273305,22205185,52025132,T2241022,21621091,22021001,and 22121001)the 111 Project(Nos.B17027 and B16029)+3 种基金the National Science Foundation of Fujian Province of China(No.2022J02059)Fundamental Research Funds for the Central Universities(20720230048)the Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(No.RD2022070601)the New Cornerstone Science Foundation through the XPLORER PRIZE.
文摘Glass-based nanochannels have become powerful tools for chemi-cal and biological sensing due to their advantages of easy prepara-tion,flexible modification,and high sensitivity.Lately,research on ion transport behaviors in glass-based nanochannels and their applications in nanofluidic iontronics has gradually become a focus,including various ion transport behaviors such as resistive-pulse,ion rectification,ionic current memory,etc.In this review,we summarize the progress of manufacturing methods for glass-based nanochannels and discuss several typical ion transport behaviors of glass-based nanochannels,as well as the main application scenarios of glass-based nanochannels in terms of biosensing,detection,and neuromorphic functions.The enormous assistance of artificial intel-ligence in the standardized manufacturing process of glass-based nanochannels was anticipated,and the potential development of glass-based nanochannels in achieving neuromorphic functions was expected.
基金supported by the National Natural Science Foundation of China(Grant No.52176070)。
文摘Membrane fouling inevitably occurs during nanofluidic reverse electrodialysis.Herein,the impact of multi-fouling on the energy conversion performance of negatively charged conical nanochannels under asymmetrical configurations is systematically investigated.The results reveal that in Configuration I,where a high-concentration solution is applied at the tip side,at small concentration ratios,multiple foulings reduce the electric power.In Configuration II,where a low-concentration solution is applied at the tip side,multiple foulings near the base side contribute to the electric power.Any fouling that formed near the lowconcentration entrance diminished the electric power and energy conversion efficiency.Multi-fouling lowered the electrical power consumption by 69.27%and 99.94%in Configurations I and II,respectively.In Configuration I,the electric power first increased with increasing fouling surface charge density,reached its maximum value,and thereafter decreased.In Configuration II,the electric power first decreased with increasing fouling surface charge density,reached its minimum value,and thereafter increased.Large negative or positive charge densities of fouling contribute to the electric power and energy conversion efficiency.
基金supported by Beijing Natural Science Foundation(Nos.2232037 and 2242035)the National Natural Science Foundation of China(Nos.22005012,22105012 and 51803183)+1 种基金Chunhui Plan Cooperative Project of Ministry of Education(No.202201298)the China Postdoctoral Science Foundation Funded Project(No.2023M733520).
文摘Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators.
基金supported by the National Natu-ral Science Foundation of China(No.U2230126)the Natural Science Foundation of Zhejiang Province(No.LZ23E010001)+1 种基金This work was co-funded by the European Union under the Project Robotics and Advanced Industrial Production(Reg.No.CZ.02.01.01/00/22_008/0004590)supported by the Ministry of Education,Youth and Sports of the Czech Repub-lic through the e-INFRA CZ grant number ID:90140.Access to the computational infrastructure of the OP VVV funded Project No.CZ.02.1.01/0.0/0.0/16_019/0000765“Research Center for Informat-ics”and the use of the VESTA software[https://doi.org/10.1107/S0021889808012016]are also acknowledged.The authors thank the staffof HIRFL for the help with the irradiation experiment and the support of the Sharing Service Platform of CAS Large Re-search Infrastructures(2022-HIRFL-ZD-002017)。
文摘Cr coatings,as protective coatings of Zr-alloy fuel claddings,inevitably suffer from irradiation damage before they would possibly run into the accident condition.This study evaluates the radiation and oxidation tolerance of three Cr-based coatings with different microstructures(Cr,CrAlSi,and CrAlSiN)through He2+ion irradiation and 1200℃ steam oxidation.The Cr and CrAlSi coatings experienced significant structural degradation,characterized by He bubble aggregation and amplified Kirkendall effects at elevated temperatures.In contrast,the irradiated CrAlSiN coating maintained structural integrity without measurable irradiation hardening.Following annealing at 800℃ for 30 min,approximately 40%of injected He atoms were released,indicating a“self-healing”mechanism.The mechanism is attributed to uniformly distributed,low-density channels that act as sinks and release paths for irradiation-induced defects.Density functional theory simulations suggest that N atoms promote significant rearrangement of ions surrounding the free volume,inhibiting the formation of sites capable of trapping He atoms.Moreover,the CrAlSiN coating exhibited superior oxidation resistance compared to the Cr and CrAlSi coatings,even under high-temperature steam conditions.Notably,the irradiated CrAlSiN sample displayed a significantly thinner oxide scale compared to the pristine one(almost half),owing to a more protective oxide scale and rapid outward diffusion of Cr,Al,and Si through nanochannel veins.These findings illuminate the effects of structure and composition on irradiation and oxidation behavior in Cr-based coatings,offering insights for developing new-generation accident-tolerance fuel coatings for Zr-alloy claddings.
基金financial support by the National Key R&D Program of China(2021YFA1200403,2020YFA0211200)the National Natural Science Foundation of China(22090050,21974128,21874121,52003257,22104040)+2 种基金the Joint NSFC-ISF Research Grant Program(Grant No:22161142020)the Hubei Provincial Natural Science Foundation of China(2020CFA037)the Zhejiang Provincial Natural Science Foundation of China under Grant No.LD21B050001.
文摘Cancers and chronic diseases have always been global health problems. The occurrence and development of such diseases are closely related to the abnormalities of proteins, nucleic acids, ions or small molecules in the body. Nowadays, nanopores/nanochannels have emerged as a powerful platform for detecting these biomolecules based on the electrical signal variation caused by biomolecules passing. However, detection relied on the electrical signal easily suffered from the clogging defects, low throughput, and strong background signals. Fortunately, the emergence of designing nanopores/nanochannels based on electrical and optical dual signal response has brought innovative impetus to biological detection, which can also identify the chemical compositions and conformations of the biomolecules. In this review, we summarize the reasonable preparation of nanopores/nanochannels with electrical and optical dual signal response and their application in biological detection. According to different biomolecules, we divide the targets into four types, including nucleic acids, small molecules, ions and proteins. In each section, the design of representative examples and the principle of dual signal generation are introduced and discussed. Finally, the prospects and challenges of nanopores/nanochannels based on electrical and optical dual signal response are also discussed.
基金We appreciate the financial support from the National Natural Science Foundation of China(Grant Nos.51838009 and 51925806)Science&Technology Commission of Shanghai Municipality(Nos.18DZ1206703 and 19DZ1204503).
文摘Metal organic framework(MOF)incorporated thin-film nanocomposite(TFN)membranes have the potential to enhance the removal of endocrine disrupting compounds(EDCs).In MOF-TFN membranes,water transport nanochannels include(i)pores of polyamide layer,(ii)pores in MOFs and(iii)channels around MOFs(polyamide-MOF interface).However,information on how to tune the nanochannels to enhance EDCs rejection is scarce,impeding the refinement of TFN membranes toward efficient removal of EDCs.In this study,by changing the polyamide properties,the water transport nanochannels could be confined primarily in pores of MOFs when the polyamide layer became dense.Interestingly,the improved rejection of EDCs was dependent on the water transport channels of the TFN membrane.At low monomer concentration(i.e.,loose polyamide structure),the hydrophilic nanochannels of MIL-101(Cr)in the polyamide layer could not dominate the membrane separation performance,and hence the extent of improvement in EDCs rejection was relatively low.In contrast,at high monomer concentration(i.e.,dense polyamide structure),the hydrophilic nanochannels of MIL-101(Cr)were responsible for the selective removal of hydrophobic EDCs,demonstrating that the manipulation of water transport nanochannels in the TFN membrane could successfully overcome the permeability and EDCs rejection trade-off.Our results highlight the potential of tuning primary selective nanochannels of MOF-TFN membranes for the efficient removal of EDCs.
基金supported by National Natural Science Foundation of China(Nos.22174016,22374019,and 22209025)Natural Science Foundation of Jiangsu Province(No.BK20220799).
文摘Nanochannel technology based on ionic current rectification has emerged as a powerful tool for the detection of biomolecules owing to unique advantages.Nevertheless,existing nanochannel sensors mainly focus on the detection of targets in solution or inside the cells,moreover,they only have a single function,greatly limiting their application.Herein,we fabricated SuperDNA self-assembled conical nanochannel,which was clamped in the middle of self-made device for two functions:Online detecting living cells released TNF-αand studying intercellular communication.Polyethylene terephthalate(PET)membrane incubated tumor associated macrophages and tumor cells was rolled up and inserted into the left and right chamber of the device,respectively.Through monitoring the ion current change in the nanochannel,tumor associated macrophages released TNF-αcould be in situ and noninvasive detected with a detection limit of 0.23 pg/mL.Furthermore,the secreted TNF-αinduced epithelial-mesenchymal transformation of tumor cells in the right chamber was also studied.The presented strategy displayed outstanding performance and multi-function,providing a promising platform for in situ non-destructive detection of cell secretions and related intercellular communication analysis.
基金supported by the National Key R&D Program of China(Grant No.2021YFA1601400)the National Natural Science Foundation of China(Grant Nos.12241201,1197283,12375287,and U1632271).
文摘A systematic understanding of the mechanism in the rectification and capacitance of nanochannels and their regulation with the electrolyte concentration and electrical bias is pivotal for its wide applications to nanofluidic electronics,ion separation,energy storage,and molecule sensing.Single unipolar and bipolar cylindrical nanochannels through polymer film were fabricated using single ion bombardment and track etching.Cyclic voltammetry results show that the bipolar nanochannel switches from rectification to capacitance as the electrolyte concentration decreases.Electrochemical impedance spectroscopy revealed that the capacitive impedance fraction in the bipolar nanochannel is regulated by electrolyte concentration and voltage.The switch from rectification to capacitance in the polymer nanochannel is well explained through a fluidic p-n junction model with a variable ion depletion layer regulated by the applied bias voltage,which is supported by the multi-physics simulation using Poisson-Nernst-Planck and Navier-Stokes solution.This work provides a mechanistic insight into the ionic current rectification and ionic capacitance in complex ionic nanochannels and paves the way for biomimetic nanofluidic electronics design.
基金funded by the National Natural Science Foundation of China[52106246]the Postgraduate Research&Practice innovation Program of Jiangsu Province[KYCX24_1641].
文摘Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy fromthe salinity gradient energy.However,the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance,especially the trade-offs between ion selectivity and mass transfer in nanochannels,of NRED poses a great challenge to achieving breakthroughs in energy conversion processes.This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors,including the nanochannel configuration,the temperature field,and the concentration difference,on the energy conversion processes of NRED.In this work,a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications,thereby enhancing the realism and applicability of our analysis.Numerical results reveal that the application of a temperature gradient,which is oriented in opposition to the concentration gradient,enhances the ion transportation and selectivity simultaneously,leading to an enhancement in both output power and energy conversion efficiency.Additionally,the increased fluctuation of the nanochannel wall from s=0 to s=0.08 improves ion selectivity yet raises ion transport resistance,resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current.Furthermore,with increasing the concentration ratio cH/cL from 10 to 1000,either within a fixed temperature field or at a constant dimensionless amplitude,the maximumpower consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences amonotonic decrease across this entire range of concentration ratios.Finally,uponmodifying the operational parameters fromthe baseline condition of s=0,c_(H)/c_(L)=10,andΔT=0 K to the targetedconditionof s=0.08,c_(H)/c_(L)=50,andΔT=25 K,there is a concerted improvement observed in the open-circuit potential,short-circuit current,andmaximumpower,with respective increments of 8.86%,204.97%,and 232.01%,but a reduction in cation transfer number with a notable decrease of 15.37%.
