Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,ene...Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,energy conversion through nanofluidic channels is still facing considerable challenges.Here,a facile and efficient strategy to enhance osmotic energy harvesting based on drastically increasing surface charge density of MXenes subnanochannels via oxygen plasma is proposed.This plasma could break Ti–C bonds in the MXenes subnanochannels and effectively facilitate the formation of more Ti–O,C═O,O–OH,and rutile with a stronger negative charge and work function,which leads the surface potential of MXenes membrane to increase from 205 to 430 mV.This significant rise of surface charge endows the MXenes membrane with high cation selectivity,which could make the output power density of the MXenes membrane increase by 248.2%,reaching a high value of 5.92Wm^(−2) in the artificial sea‐river water system.Furthermore,with the assistance of low‐quality heat at 50℃,the osmotic power is enhanced to an ultrahigh value of 9.68Wm^(−2),which outperforms those of the state‐of‐the‐art two‐dimensional(2D)nanochannel membranes.This exciting breakthrough demonstrates the enormous potential of the facile plasma‐treated 2D membranes for osmotic energy harvesting.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
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 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
U-shaped micro-nanochannels can generate significant flow disturbance as well as locally amplified electric field, which gives itself potential to be microfluidic mixers, electrokinetic pumps,and even cell lysis proce...U-shaped micro-nanochannels can generate significant flow disturbance as well as locally amplified electric field, which gives itself potential to be microfluidic mixers, electrokinetic pumps,and even cell lysis process. Numerical simulation is utilized in this work to study the hidden characteristics of the U-shaped micro-nanochannel system, and the effects of key controlling parameters(the external voltage and pressure) on the device output metrics(current, maximum values of electric field, shear stress and flow velocity) were evaluated. A large portion of current flowing through the whole system goes through the nanochannels, rather than the middle part of the microchannel, with its value increasing linearly with the increase of voltage. Due to the local ion depletion near micro-nanofluidic junction, significantly enhanced electric field(as much as 15 fold at V=1 V and P_0=0) as well as strong shear stress(leading to electrokinetic flow) is generated.With increasing external pressure, both electric field and shear stress can be increased initially(due to shortening of depletion region length), but are suppressed eventually at higher pressure due to the destruction of ion depletion layer. Insights gained from this study could be useful for designing nonlinear electrokinetic pumps and other systems.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 guest water molecules. The bulk structure is consolidated by O–H···O bridgings within the nanochannels and by coulombic interactions.展开更多
Nonmechanical pumping of liquids is of key importance for applications from the biomedical microfluidic chip to drug delivery systems. In this paper, a new electrokinetic pump （EOP） system with polycarbonate nanoeha...Nonmechanical pumping of liquids is of key importance for applications from the biomedical microfluidic chip to drug delivery systems. In this paper, a new electrokinetic pump （EOP） system with polycarbonate nanoehannel membrane sandwiched between two membrane holders was constructed. The pump was tested with water and phosphate buffer at 1-6 V applied voltage, the maximum pressure and flow rate are 0.32 MPa （3.2 atm） and 4.2 μL/min for phosphate buffer, respectively. This proof-of-concept pump shows its potential use for drugs or chemical agents delivery by the usage of different membrane materials.展开更多
We consider an incompressible fluid in a rectangular nanochannel. We solve numerically the three dimensional Fourier heat equation to get the steady solution for the temperature. Then we set and solve the Langevin equ...We consider an incompressible fluid in a rectangular nanochannel. We solve numerically the three dimensional Fourier heat equation to get the steady solution for the temperature. Then we set and solve the Langevin equation for the temperature. We have developed equations in order to determine relaxation time of the temperature fluctuations, τT = 4.62 × 10-10s. We have performed a spectral analysis of the thermal fluctuations, with the result that temporal correlations are in the one-digit ps range, and the thermal noise excites the thermal modes in the two-digit GHz range. Also we observe long-range spatial correlation up to more than half the size of the cell, 600 nm;the wave number, q, is in the 106 m-1 range. We have also determined two thermal relaxation lengths in the z direction: l1 = 1.18 nm and l2 = 9.86 nm.展开更多
Reaction of Ba0.50[Ag2Cr(C2O4)3]·5H2O with Ag2SO4 in an aqueous solution of sulfuric acid (pH ≈ 3) yielded the silver(I)/chromium(III) oxalate salt H0.50[Ag2.50Cr(C2O4)3]·5H2O (1). Compound 1 can be best de...Reaction of Ba0.50[Ag2Cr(C2O4)3]·5H2O with Ag2SO4 in an aqueous solution of sulfuric acid (pH ≈ 3) yielded the silver(I)/chromium(III) oxalate salt H0.50[Ag2.50Cr(C2O4)3]·5H2O (1). Compound 1 can be best described as an anionic silver-deficient oxalatochromate(III) complex [Ag2.50Cr(C2O4)3]0.5- with nanochannels containing hydrogen-bonded water molecules and protons. Thermal analyses show significant weight losses corresponding to the elimination of water molecules of crystallization followed by the decomposition of the network.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
Nanochannels have made great progress and are a promising platform for detecting a series of targets.However,most nanochannels are modified on the inner wall,while ignoring the outer surface.Here,we modified the outer...Nanochannels have made great progress and are a promising platform for detecting a series of targets.However,most nanochannels are modified on the inner wall,while ignoring the outer surface.Here,we modified the outer surface of nanochannels with hydrogel.Different from other reported outer-surface modification methods,we directly cover nanochannels with hydrogel to form heterogeneous membrane.The selected hydrogel hardly adsorbs other ions and shows specific adsorption for Cr(VI).The adsorption sites in hydrogel are homogeneous,and Cr(VI)adsorption onto hydrogel is endothermic and spontaneous.The charge in hydrogel changes after Cr(VI)adsorption,and the resulting current changes can be used for the detection of Cr(VI)with the detection limit of 10−11 mol/L.Our platform is expected to be used for Cr(VI)detection in living organisms,especially within cells.This work provides a new approach for outer-surface modification of nanochannels and offers a new choice for nanochannel detection platforms.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
.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
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
Two-dimensional(2D)material-based membrane separation has attracted increasing attention due to its promising performance compared with traditional membranes.However,in-depth understanding of water transportation beha...Two-dimensional(2D)material-based membrane separation has attracted increasing attention due to its promising performance compared with traditional membranes.However,in-depth understanding of water transportation behavior in such confined nanochannels is still lacking,which hinders the development of 2D nanosheets membranes.Herein,we investigated water confined in graphene or MoS_(2)nanochannels by molecular dynamics(MD)simulations and found water’s diffusivity always varied linearly with their mean square displacement along z direction(Δz^(2))when system variables(e.g.,water molecules’number,channel height,nonbonded interaction parameter,harmonic potential constraining water’s z-coordinate)changed.Such linear correlation applies to different water models and different force fields(FFs)of channel walls(e.g.,different Lennard–Jones parameters or even flexible FF),no matter whether water molecules form 3-,2-,or quasi-2-layer structure in the nanochannel.This indicates,though water molecules’motion along z direction(z-fluctuation,confined within 1 nm)and that in xy plane(xydiffusion)are entirely different,they are tightly coupled:Violent z-fluctuation would produce more transient void to facilitate xydiffusion,which is to the sharp contrary of bulk water,where motions in x,y,z directions are symmetric,but independent.Our work could help design high performance 2D nanochannels and discover more novel principles in nano-fluidics and membrane separation fields.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
With the increasing requirements of reliable and environmentally friendly energy resources, porous materials for sustainable energy conversion technologies have attracted intensive interest in the past decades. As an ...With the increasing requirements of reliable and environmentally friendly energy resources, porous materials for sustainable energy conversion technologies have attracted intensive interest in the past decades. As an important block of porous materials, biomimetic smart nanochannels （BSN） have been developed rapidly into an attractive field for their well-tunable geometry and chemistry. With inspiration from nature, many works have been reported to utilize BSN to harvest clean energy. In this review, we summarize recent progress in the BSN for power harvesting from four parts of brief introduction of BSN, biological prototypes for power harvesting, BSN-based energy conversion, and conclusion and outlook. Overall, by learning from nature, exploiting new avenues and improving the performance of BSN, a number of exciting developments in the near future may be anticipated.展开更多
基金National Natural Science Foundation of China,Grant/Award Number:52175174China Postdoctoral Science Foundation,Grant/Award Number:2022M721791National Key Research and Development Program of China,Grant/Award Number:2020YFA0711003。
文摘Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,energy conversion through nanofluidic channels is still facing considerable challenges.Here,a facile and efficient strategy to enhance osmotic energy harvesting based on drastically increasing surface charge density of MXenes subnanochannels via oxygen plasma is proposed.This plasma could break Ti–C bonds in the MXenes subnanochannels and effectively facilitate the formation of more Ti–O,C═O,O–OH,and rutile with a stronger negative charge and work function,which leads the surface potential of MXenes membrane to increase from 205 to 430 mV.This significant rise of surface charge endows the MXenes membrane with high cation selectivity,which could make the output power density of the MXenes membrane increase by 248.2%,reaching a high value of 5.92Wm^(−2) in the artificial sea‐river water system.Furthermore,with the assistance of low‐quality heat at 50℃,the osmotic power is enhanced to an ultrahigh value of 9.68Wm^(−2),which outperforms those of the state‐of‐the‐art two‐dimensional(2D)nanochannel membranes.This exciting breakthrough demonstrates the enormous potential of the facile plasma‐treated 2D membranes for osmotic energy harvesting.
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.
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 Intergovernmental International Science,Technology and Innovation Cooperation Key Project of the National Key R&D Programme(2016YFE0105900)the National Natural Science Foundation of China(21576130and 11372229)Kuwait Foundation for the Advancement of Sciences(Kuwait-MIT signature project,Project code:P31475EC01)
文摘U-shaped micro-nanochannels can generate significant flow disturbance as well as locally amplified electric field, which gives itself potential to be microfluidic mixers, electrokinetic pumps,and even cell lysis process. Numerical simulation is utilized in this work to study the hidden characteristics of the U-shaped micro-nanochannel system, and the effects of key controlling parameters(the external voltage and pressure) on the device output metrics(current, maximum values of electric field, shear stress and flow velocity) were evaluated. A large portion of current flowing through the whole system goes through the nanochannels, rather than the middle part of the microchannel, with its value increasing linearly with the increase of voltage. Due to the local ion depletion near micro-nanofluidic junction, significantly enhanced electric field(as much as 15 fold at V=1 V and P_0=0) as well as strong shear stress(leading to electrokinetic flow) is generated.With increasing external pressure, both electric field and shear stress can be increased initially(due to shortening of depletion region length), but are suppressed eventually at higher pressure due to the destruction of ion depletion layer. Insights gained from this study could be useful for designing nonlinear electrokinetic pumps and other systems.
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 guest water molecules. The bulk structure is consolidated by O–H···O bridgings within the nanochannels and by coulombic interactions.
文摘Nonmechanical pumping of liquids is of key importance for applications from the biomedical microfluidic chip to drug delivery systems. In this paper, a new electrokinetic pump （EOP） system with polycarbonate nanoehannel membrane sandwiched between two membrane holders was constructed. The pump was tested with water and phosphate buffer at 1-6 V applied voltage, the maximum pressure and flow rate are 0.32 MPa （3.2 atm） and 4.2 μL/min for phosphate buffer, respectively. This proof-of-concept pump shows its potential use for drugs or chemical agents delivery by the usage of different membrane materials.
文摘We consider an incompressible fluid in a rectangular nanochannel. We solve numerically the three dimensional Fourier heat equation to get the steady solution for the temperature. Then we set and solve the Langevin equation for the temperature. We have developed equations in order to determine relaxation time of the temperature fluctuations, τT = 4.62 × 10-10s. We have performed a spectral analysis of the thermal fluctuations, with the result that temporal correlations are in the one-digit ps range, and the thermal noise excites the thermal modes in the two-digit GHz range. Also we observe long-range spatial correlation up to more than half the size of the cell, 600 nm;the wave number, q, is in the 106 m-1 range. We have also determined two thermal relaxation lengths in the z direction: l1 = 1.18 nm and l2 = 9.86 nm.
文摘Reaction of Ba0.50[Ag2Cr(C2O4)3]·5H2O with Ag2SO4 in an aqueous solution of sulfuric acid (pH ≈ 3) yielded the silver(I)/chromium(III) oxalate salt H0.50[Ag2.50Cr(C2O4)3]·5H2O (1). Compound 1 can be best described as an anionic silver-deficient oxalatochromate(III) complex [Ag2.50Cr(C2O4)3]0.5- with nanochannels containing hydrogen-bonded water molecules and protons. Thermal analyses show significant weight losses corresponding to the elimination of water molecules of crystallization followed by the decomposition of the network.
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 the National Natural Science Foundation of China(No.22090050)the National Key R&D Program of China(No.2021YFA1200403)the Joint National Natural Science Foundation of China-Israel Science Foundation(NSFC-ISF)Research Grant Program(No.22161142020).
文摘Nanochannels have made great progress and are a promising platform for detecting a series of targets.However,most nanochannels are modified on the inner wall,while ignoring the outer surface.Here,we modified the outer surface of nanochannels with hydrogel.Different from other reported outer-surface modification methods,we directly cover nanochannels with hydrogel to form heterogeneous membrane.The selected hydrogel hardly adsorbs other ions and shows specific adsorption for Cr(VI).The adsorption sites in hydrogel are homogeneous,and Cr(VI)adsorption onto hydrogel is endothermic and spontaneous.The charge in hydrogel changes after Cr(VI)adsorption,and the resulting current changes can be used for the detection of Cr(VI)with the detection limit of 10−11 mol/L.Our platform is expected to be used for Cr(VI)detection in living organisms,especially within cells.This work provides a new approach for outer-surface modification of nanochannels and offers a new choice for nanochannel detection platforms.
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 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.
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the National Natural Science Foundation of China(Nos.22078104,22022805,and 22078107)the National Key Research and Development Program(No.2021YFB3802500)+2 种基金the financial support from the Science and Technology Key Project of Guangdong Province(No.2020B010188002)State Key Laboratory of Pulp and Paper Engineering(No.2022PY04)Fundamental Research Funds for the Central Universities(No.2022ZYGXZR010).
文摘Two-dimensional(2D)material-based membrane separation has attracted increasing attention due to its promising performance compared with traditional membranes.However,in-depth understanding of water transportation behavior in such confined nanochannels is still lacking,which hinders the development of 2D nanosheets membranes.Herein,we investigated water confined in graphene or MoS_(2)nanochannels by molecular dynamics(MD)simulations and found water’s diffusivity always varied linearly with their mean square displacement along z direction(Δz^(2))when system variables(e.g.,water molecules’number,channel height,nonbonded interaction parameter,harmonic potential constraining water’s z-coordinate)changed.Such linear correlation applies to different water models and different force fields(FFs)of channel walls(e.g.,different Lennard–Jones parameters or even flexible FF),no matter whether water molecules form 3-,2-,or quasi-2-layer structure in the nanochannel.This indicates,though water molecules’motion along z direction(z-fluctuation,confined within 1 nm)and that in xy plane(xydiffusion)are entirely different,they are tightly coupled:Violent z-fluctuation would produce more transient void to facilitate xydiffusion,which is to the sharp contrary of bulk water,where motions in x,y,z directions are symmetric,but independent.Our work could help design high performance 2D nanochannels and discover more novel principles in nano-fluidics and membrane separation fields.
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This work was supported by the National Natural Science Foundation of China （Nos. 21171171, 21434003, and 91427303）, and the Key Research Program of the Chinese Academy of Sciences （No. KJZD-EW-M03）.
文摘With the increasing requirements of reliable and environmentally friendly energy resources, porous materials for sustainable energy conversion technologies have attracted intensive interest in the past decades. As an important block of porous materials, biomimetic smart nanochannels （BSN） have been developed rapidly into an attractive field for their well-tunable geometry and chemistry. With inspiration from nature, many works have been reported to utilize BSN to harvest clean energy. In this review, we summarize recent progress in the BSN for power harvesting from four parts of brief introduction of BSN, biological prototypes for power harvesting, BSN-based energy conversion, and conclusion and outlook. Overall, by learning from nature, exploiting new avenues and improving the performance of BSN, a number of exciting developments in the near future may be anticipated.
