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
The diffusion,adsorption/desorption behaviors of water molecules and hydrogen molecules are of great importance in heterogeneous photocatalytic hydrogen production.In the study of structure-property-performance relati...The diffusion,adsorption/desorption behaviors of water molecules and hydrogen molecules are of great importance in heterogeneous photocatalytic hydrogen production.In the study of structure-property-performance relationships,nanoconfined space provides an ideal platform to promote mass diffusion and transfer due to their extraordinary properties that are different from the bulk systems.Herein,we designed and prepared a nanoconfined CdS@SiO_(2)-NH_(2) nanoreactor,whose shell is composed of amino-functionalized silica nanochannels,and encapsulates spherical CdS as a photocatalyst inside.Experimental and simulated results reveal that the amino-functionalized nanochannels promote water molecules’and hydrogen molecules’directional diffusion and transport.Water molecules are enriched in the nanocavity between the core and the shell,and promote the interfacial photocatalytic reaction.As a result,the maximized water enrichment and minimized hydrogen-occupied active sites enable photocatalyst with optimized mass transfer kinetics and localization electron distribution on the CdS surface,leading to superior hydrogen production performance with activity as high as 37.1 mmol·g^(-1)·h^(-1).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
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
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
There are many elaborate masterpieces exist in natural world. Learning from nature, people developed serial intelligent biomimetic devices. Biomimetic smart nanochannels received widespread attention for mimicking bio...There are many elaborate masterpieces exist in natural world. Learning from nature, people developed serial intelligent biomimetic devices. Biomimetic smart nanochannels received widespread attention for mimicking biological processes in bodies. Excellent stability, tailorable surface characteristics and nano-size effects rend polymer single nanochannel an ideal candidate for constructing sensitive and reproducible biosensors. Nanochannels are responsive for special analytes while appropriate recognition elements are modified in channels wall. In this review, we summarized recent works in contructing biosensors that are using polymer single nanochannels for detecting various analytes.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
The atomic force microscopy (AFM)-based nanomachining of nanochannels on silicon oxide surfaces is investigated both theoretically and experimentally. The relationships of nanochannel depth versus cutting velocity,nan...The atomic force microscopy (AFM)-based nanomachining of nanochannels on silicon oxide surfaces is investigated both theoretically and experimentally. The relationships of nanochannel depth versus cutting velocity,nanochannel depth versus normal force,friction force versus cutting velocity,and friction force versus normal force are systematically studied. Using the derived theory and fabrication method,a nanochannel with an expected depth can be machined simply by controlling the vertical deflection signal on the position sensitive detector of AFM. The theoretical analysis and fabrication method can be effectively used for AFM-based fabrication of nanochannels.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
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
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
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 Natural Science Foundation of China(No.22108214)Joint Funds of the National Natural Science Foundation of China(No.U22A20391).
文摘The diffusion,adsorption/desorption behaviors of water molecules and hydrogen molecules are of great importance in heterogeneous photocatalytic hydrogen production.In the study of structure-property-performance relationships,nanoconfined space provides an ideal platform to promote mass diffusion and transfer due to their extraordinary properties that are different from the bulk systems.Herein,we designed and prepared a nanoconfined CdS@SiO_(2)-NH_(2) nanoreactor,whose shell is composed of amino-functionalized silica nanochannels,and encapsulates spherical CdS as a photocatalyst inside.Experimental and simulated results reveal that the amino-functionalized nanochannels promote water molecules’and hydrogen molecules’directional diffusion and transport.Water molecules are enriched in the nanocavity between the core and the shell,and promote the interfacial photocatalytic reaction.As a result,the maximized water enrichment and minimized hydrogen-occupied active sites enable photocatalyst with optimized mass transfer kinetics and localization electron distribution on the CdS surface,leading to superior hydrogen production performance with activity as high as 37.1 mmol·g^(-1)·h^(-1).
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supported by the National Basic Research Program of China (2011CB935700)National Natural Science Foundation of China(21201170, 11290163, 21121001, 91127025, 21171171)+1 种基金Key Research Program of the Chinese Academy of Sciences (KJZD-EW-M01)Beijing National Laboratory for Molecular Sciences (CMS-PY-201243)
文摘There are many elaborate masterpieces exist in natural world. Learning from nature, people developed serial intelligent biomimetic devices. Biomimetic smart nanochannels received widespread attention for mimicking biological processes in bodies. Excellent stability, tailorable surface characteristics and nano-size effects rend polymer single nanochannel an ideal candidate for constructing sensitive and reproducible biosensors. Nanochannels are responsive for special analytes while appropriate recognition elements are modified in channels wall. In this review, we summarized recent works in contructing biosensors that are using polymer single nanochannels for detecting various analytes.
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.
基金supported by the National High-Tech Research and Development Program of China (2009AA04Z313, 2009AA03Z316)the CAS/SAFEA International Partnership Program for Creative Research Teams
文摘The atomic force microscopy (AFM)-based nanomachining of nanochannels on silicon oxide surfaces is investigated both theoretically and experimentally. The relationships of nanochannel depth versus cutting velocity,nanochannel depth versus normal force,friction force versus cutting velocity,and friction force versus normal force are systematically studied. Using the derived theory and fabrication method,a nanochannel with an expected depth can be machined simply by controlling the vertical deflection signal on the position sensitive detector of AFM. The theoretical analysis and fabrication method can be effectively used for AFM-based fabrication of nanochannels.
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.
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.
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.
