The new hot spot slowly rising! Nanofluids come of age, more than 20 Nature, Science bring you a taste
Studies nanofluids is the transmission behavior of matter in the nanometer-scale channel. Although solid-state physics to nano-fluidics has been studied for a long time, but because of nano-fluid systems needed to learn nanofluidic devices is a major bottleneck hindering the development of the area, so scientists molecules, ions and other substances in the nanochannel experimental study of the behavior of the transmission currently only 15 years short time. In recent years with the emergence of a large number of fine processing technology of new nano-materials and nano-channel preparation, research progress in the field of nanofluids has undergone tremendous leap forward, based on current trends existing research and nano-fluidics, France Ecole Lydéric Bocquet Teachers College professor recently in an article in Nature Materials theory that: nano-fluidics come of age! Why Lydéric Bocquet professors have such feelings and opinions do? In this review, Prof. Lydéric Bocquet lists the following four points reasons:
(1) the type of nanomaterial is increased (in particular in the emergence of a two-dimensional graphene material represented) that the various structures and shapes adjustable preparation nanochannel achieved; (2) advent of advanced equipment and techniques enable scientists to explore not only the transmission behavior of the material inside the passageway, could also examine properties of the fluid in the passage inside the body; a plurality of intended substance (3) a nanoscale unexpected behavior and \”strange\” features have been revealed; (4) the basis of these findings is expected to solve scientific applications film \”Difficult issues\”, especially water – the challenges in the energy sector.
Here, Xiao Bian selected some published in Nature, Science (and sub-published) research field of nano-fluidics, they come to focus on major technological advances in this area over the past few years and found that, as well as their on membrane separation technology and water – the impact of energy and technology challenges of the future.
[a. Preparation of Nano-way channel]
First, the core step in nano-fluidics research is to build a stable nano-channels, through the analysis of these research results, we conclude that the five most commonly used method for preparing nanochannel.
(1) Direct method punctured
This method is generally a two-dimensional material oligonucleotides layer disposed on the substrate by using a high energy laser electron beam, an oxygen plasma or other chemicalsIts pore selective etching, to adjust the size and density of the nano-holes at the exposure time by adjusting the etch source two-dimensional material. For example Oak Ridge National Laboratory research team Prof. Shannon M. Mahurin using oxygen plasma etching preparing a porous monolithic layer graphene film [Nature Nanotechnology, 10 (5), 459-464; FIG. 1A]; Hyung Gyu Institute of Technology Zurich Professor Park team with KOH etching to obtain a graphene bilayer regular array of nanoholes having gas separation membrane [Science, 344 (6181), 289-292; FIG. 1B].
(2) van der Waals primary force assembly method
Van der Waals forces assembling method relies on the strong van der Waals force between the two-dimensional material to cause passage constructed two-dimensional stable. The preparation process can be divided into five steps, as shown in FIG. 2: The first step is made on a substrate of a rectangular hole; second step is the hole covered with the substrate material (e.g., graphite, h-BN) ; the third step is to contain different layers, stripes having a pitch of two-dimensional material and the like coated on the base material, labeled spacer layer (spacer layer is the height of the nano / Amy channel height); the fourth step is to the spacer material layer and the substrate portion overlapping oblong holes etched away to form a square hole of a uniform size; fifth step is covered with a layer of the same material underlying the top layer material on the surface of the spacer layer having a stripe structure [specific preparation process can refer to Nature, 2016, 538 (7624): 222-225].
(3) vacuum self-assembly
is a self-assembly vacuo dimensional material dispersion liquid vacuum filtration of the resulting two-dimensional manner the material layer deposited films prepared in this way is simple, it can be controlled by adjusting the size of the nano channel spacing layer between a two-dimensional slice, and the concentration or amount of channel dispersion by controlling the film thickness, it is currently the most common method for preparing a nanochannel.
(4) The intrinsic nanochannel
The carbon nanotubes, BN nanotubes itself has such nano channel, can be adjusted by controlling the diameter of the preparation process, so as to realize the size of the nanopore control. Meanwhile, since the nanotubes is difficult to form a complete fluid passage separately, so in the experiment generally the nanotubes embedded in some matrix for subsequent studies, such as Lawrence Livermore National Laboratory Prof. Aleksandr Noy team carbon nano embedded in the tube to obtain a composite membrane phospholipid nanochannel [Science, 357 (6353), 792-796].
(5) nanochannel organic synthesis
The method relies mainly on several Top-Down prepared in a manner nanochannel, there is a high equipment requirements and disadvantages such as poor stability channel pair. The organic synthesis method nanochannel avoid these disadvantages, but also allows for more precise control of the nanochannel. For example Pennsylvania State University Manish Kumar, Ratul Chowdhury joint team of the University of Illinois Professor Aleksei Aksimentiev professor team synthesized three-dimensional communicating pores having an internal porous macromolecular PAH  s, which channel can be accurate to 1Å [Nat.Nanotechnol. 15 , 73-79 (2020)]
[II. Major technological advances and discoveries]
substance has a difference significantly different from macro-scale channels and unique phenomenon in the ultimate scale (nano, Amy) conduct an internal channel transmission, such as transmission and rapid transmission mechanism within the nanochannel substance over changes, abnormal changes in the physical properties or structure in the nanometer water confined space, the protons pass through the monolayer graphene and h-BN, and the like ions Coulomb blockade effects in the nanometer scale. Here we have chosen the 11 documents to do a brief introduction to these major technological advances and discoveries.
1.Nature: No water molecules inside the carbon nanotubes high frictionSpeed flow
research group Professor Derek Stein French Ecole Normale Lydéric Bocquet joint professor at Brown University found that carbon nanotubes depend on internal radiation slip can flow without friction of water molecules inside nanotubes in high-speed flow channel, have the same crystal type but different carbon tube internal electronic structure of boron nitride nanotubes is no such phenomenon, the transfer has nanochannel behavior inside the solid material on the atomic scale – the fluid interface properties of great relevance. The study, entitled \”Massive radius-dependentflow slippage in carbon nanotubes\” published in \”Nature\” journal. Original link: https: //www.nature.com/articles/nature19315
2.Nature: low-dimensional square ice crystals within the confined space
Professor AK Geim, University of Manchester, University of Ulm, Germany G Prof. .Algara-Siller Professor HAWu China University of Science United TF found hydrophobic water at room temperature between two-dimensional graphene sheets formed a square ice crystals, which ice crystals high bulk density, lattice constant of 2.83Å, be double and triple layer forming microcrystalline, while compared with the traditional structure of tetrahedral water molecules form hydrogen bonds, which has a good square symmetry ice. The study, entitled \”Square ice in graphenenanocapillaries\” published in \”Nature\” journal. Original link: https: //www.nature.com/articles/nature14295
3.Nature: abnormal rapid transport of water molecules in the channels having a two-dimensional atomic-level accuracy in the
Andre University of Manchester Professor Geim and co-workers using graphene atoms flatness obtained with atomic-level accuracy nanochannels and resizable prepared by microfabrication techniques, found that these channels can be generated inside the water molecules strong interaction with the channel walls large separation pressure (1000 bar), the water molecules in the nano-channel transmission to the capillary effect of the maximum speed can reach 1 m / s. The study, entitled \”Moleculartransport through capillaries made with atomic-scale precision\” published in \”Nature\” journal. Original link: https: //www.nature.com/articles/nature19363
4.Nature: ballistic transport of gas molecules in the two-dimensional channel
research team, Professor Andre Geim at Manchester University found that when having atomic level high surface flatness graphene or h-BN as a wall surface of the nanochannel, gas molecules produce large amounts of specular reflection inside the channel, greatly improved molecular transmission rate inside the channel, and showed significant ballistic transport mechanism ( means that when the carrier is much larger than the mean free path of the medium-scale, the carrier transport process in the medium hardly being scattered). The study, entitled \”Ballistic moleculartransport through twodimensional channels\” published in \”Nature\” journal. Original link: https:
5.Nature //www.nature.com/articles/s41586-018-0203-2: Wei Aimi two molecules within the channel / ion transport and pressure dependence of the current [ 123] Prof. AndreGeim the University of Manchester and co-workers found that the friction between the water molecules Amy dwt channel / ion channel wall material will greatly affect their transfer kinetics, and by the weak external disturbances (mechanical pressure and the electric force), transmission performance can vary widely. Found it found that low friction between water molecules / ions with graphene channel wall leads to an electroosmotic mobility μ system voltage quadratic relationship, the larger the coefficient of friction between the h-BN resulted in electroosmotic system mobility μ was a relationship between the voltage (linear relationship). The study, entitled \”Molecularstreaming and its voltage control in ångström-scale channels \”published in the\” Nature \”journal
Original link:. https: //www.nature.com/articles/s41586-019-0961-5 6.Science : ions angstrom size effect dwt channel
Professor Andre Geim University of Manchester and Prof. K. Gopinadhan joint study by the research group of graphene, super strength and MoS2 h-BN material of the three-dimensional Amy behavior transmission channel constraints internal ion found interaction space charge effects cause the inside surface of the wall of the small two-dimensional channel, when the diameter is larger than the size of the hydrated ion is still a two-dimensional channel may be transmitted at a slower rate and penetration, while this effect is significant asymmetry between the anionic and cationic same diameter. in the study, entitled \”Size effect in ion transportthrough angstrom-scale slits\” published in \”Science\” journal.
original link: https: //science.sciencemag.org/content/358/6362/511 7.Science: ultra low-k interfacial water
Professor Andre Geim of Manchester University, UK, and Professor L. Fumagalli joint Task Force the dielectric constant of the first time proved experimentally interface under water limited conditions is much lower than the ordinary environment dielectric constant of water (≈80). researchers constrained by the h-BN constructed scale of about 1nm passage water interface was measured and found that the dielectric constant of water at the interface nanoscale up to about 2, a dielectric constant between the surface of the aqueous medium such interaction results in decreased long-term anomalies deeper understanding of biological systems to each other the role of great significance. the study, entitled \”Anomalously low dielectricconstant of confined water\” published in the \”Science \”journals.
Original link: https: //science.sciencemag.org/content/360/6395/1339 8.Nature: proton transfer single-atom-thick crystals by
Professor Andre Geim of Manchester University, UK China Joint Science and Technology University professor HA Wu heat team found protons (proton is an intermediate state between electrons and atoms) have a high permeability single-layer graphene and h-BN, whereas for thicker crystals such as single disulfide molybdenum, bilayer or multi-graphene of hBN, it can not be transmitted. The researchers found that while due to the low conductivity, h-BN monolayer showed higher than the proton permeability graphene. The study, entitled \”Proton transport throughone-atom-thick crystals\” published in \”Nature\” journal.
Original link: https: //www.nature.com/articles/nature14015 9.Nature: electrically controlling the water permeability graphene oxide thin film
Professor RR Nair TF by the University of Manchester controllable electrical breakdown micron graphene oxide (GO) of the conductive film produced filaments, around which the conductive filaments form an electric field so that water molecules are ionized in the two-dimensional sheet layer film GO capillaries, thereby preventing water transport. Studies have shown that you can achieve precise control of water penetration through the process – completely blocked from ultra-fast penetrate into this for the development of artificial biological systems, tissue engineering and smart filter membrane technology has opened up a path. The study, entitled \”Electrically controlled water permeation through graphene oxide membranes\” published in \”Nature\” journal.
Original link: https: //www.nature.com/articles/s41586-018-0292-y 10.Nature nanotechnology: Fast water transfer graphene nanofluidic channel
Prof. Chuanhua Duan Boston University research group designed a new hybrid nanochannel measured single graphene nano channel water transport resistance and slip length . The results show that when graphene nano channel height change is between 0 ~ 200nm, slip length graphene channel are ≈16nm, which is between graphene and graphene surface charge properties thereof and because SiO2 substrate the interactions. The study, entitled \”Fast water transport ingraphene nanofluidic channels\” published in \”Nature Nanotechnology\” journal.
Original link: https: //www.nature.com/articles/s41565-017-0031-9 11.Nature Materials: Coulomb blockade within the nanochannel ion observed
Lausanne School of Engineering Professor Aleksandra Radenovic a single team of sub-nanometer hole transport passage of ions were measured and the ion Coulomb blockade effect was observed, experimental results ion Coulomb blockade of ion transport model to predict the behavior of the channel in the sub-nanometer, and shows that the nano-scale atomic pores help explore the ion transport behavior, which can further deepen the understanding of biological ion channels transport. The study, entitled \”Observation of ionicCoulomb blockade in nanopores\” published in \”Nature Materials\” journal.
Original link: https: //www.nature.com/articles/nmat4607 [III. Membrane materials having nanochannel]
Isolation and purification of substances in industrial production and the people\’s life Nissan actor role, wherein the core material is a material of the separation membrane separation and purification techniques. The biggest problem facing the membrane material separation factorContradictory Relations between permeability and, currently commercialized in order to ensure separation membrane separation factor and significantly higher expense of permeability, thus resulting in low efficiency of purification. Since the existing studies indicate nanochannel inner mass has a unique transmission behavior, which avoids the trade-off between permeability and selectivity – can be simultaneously improved separation factor and permeability, the separation membrane thus prepared efficiently in the future nanochannel field showed great potential. Here, we have chosen 13 research literature to make a brief introduction to the application of nano-fluidics in isolated areas.
1.Science: oligonucleotide porous layer graphene efficient gas separation membrane
Prof. Hyung Gyu Park Institute of Technology Zurich team found oligonucleotide gas layer porous graphene film to free molecular (overflow) transmission mechanism, a significant At the same time reducing the friction between the gas molecules collide with channel walls to increase the gas permeation rate, the difference in molecular weight can also be used to perform efficient intermolecular selectively permeable for gas molecules, the permeability test results show that H2 and H2 / CO2 separation coefficient can be achieved 10-2 mol m-2s-1 Pa-1 and 10, and a comprehensive performance than inorganic porous polymer gas separation membranes. The study, entitled \”Ultimate PermeationAcross Atomically Thin Porous Graphene\” published in the \”Science\” journal.
Original link: https: //science.sciencemag.org/content/344/6181/289 2.Science: graphene / h-BN membrane separation of hydrogen isotopes
Prof. AK Geim University of Manchester United Prof. M. Lozada-Hidalgo team of H + and D + in the oligonucleotide layer graphene or membrane transport behavior of h-BN have been studied and it is found in the graphene or h-BN film, the transmission speed (σH) H + average D + is much larger than the transmission rate (σD) [σH / σD≈10], caused by H + and D + dimensional material appear in the transmission speed of such differentially because H + and D + zero-point energy different –D + ions through the membrane higher energy barrier to be overcome, soSaving two-dimensional material as membrane materials have great potential in the field of hydrogen isotopes is concentrated, high energy is expected to replace the current electrolysis – distillation. The study, entitled \”Sieving hydrogen isotopes throughtwo-dimensional crystals\” published in the \”Science\” journal.
Original link: https: //science.sciencemag.org/content/351/6268/68 3.Science: precise and efficient graphene oxide membrane
Professor AK Geim, University of Manchester United RR Nair small molecule research team permeation behavior of the membrane in the micron-sized graphene oxide (GO), found that the vacuum sealing effect between the two-dimensional sheet, small molecules can not penetrate in the dry state; and submersion film GO may be the same as hydrated zeolite molecular radius greater than 4.5Å is a barrier, but smaller than the size of the molecules can be transmitted at a higher osmotic pressure between the capillary GO sheets at a faster rate. The study, entitled \”Precise and UltrafastMolecular Sieving Through Graphene Oxide Membranes\” published in the \”Science\” journal.
Original link: https: //science.sciencemag.org/content/343/6172/752 4.Science: improving the ion permeability and carbon nanotubes selected sub-nanometer hole adjustability
U.S. Lawrence Livermore national laboratory, Professor Aleksandr Noy research team prepare a hole diameter of 0.8nm carbon nanotubes protein (CNTPs), due to strong spatial limitations, hydrogen bonds between water molecules when CNTPs internal transport molecules rearrangement occurs so that the water permeation in a single chain molecule, its transmission efficiency higher than aquaporins organism an order of magnitude, while also hindering CNTPs anion permeable, thus highly selective transmission material. These features make the CNTPs an ideal material for the development of membrane separation technology. The study, entitled \”Enhanced waterpermeability and tunable ion selectivity in subnanometer carbon nanotube porins\” published in the \”Science\” journal.
Original link: https: //science.sciencemag.org/content/357/6353/792 5.Science: graphene for separation of ions and molecules / carbon nanotube composite nanofiltration membrane
Professor Quan Yuan Wuhan University joint team UCLA professor Xiangfeng Duan team developed a graphene / carbon nanotube (GNM / SWNT) composite nanofiltration membrane having excellent mechanical strength. In GNM / SWNT composite nanofiltration membrane, there is a high density GNM sub-nanometer hole transport the water molecules can be effectively, while preventing the flow of a solute ion or molecule size to achieve selective separation, the SWNT network structure acts as a microscopic support GNM physical frame, thereby ensuring the structural integrity of the GNM atoms thick. The study, entitled \”Large-area graphene-nanomesh / carbon-nanotube hybrid membranes for ionic and molecularnanofiltration\” published in the \”Science\” journal.
Original link: https: //science.sciencemag.org/content/364/6445/1057 6.Science: graphene for separation of ions and molecules / carbon nanotube composite nanofiltration membrane
Miao Yu South Carolina State University research group by a simple filtration process a thin thickness of about 1.8nm graphene oxide (GO) films prepared using a selective membrane GO structural defects, GO film H2 / CO2 and H2 / N2 selectivity of the mixture up to 3400 and 900, respectively,Higher than the most advanced microporous film one to two orders of magnitude, and therefore is an ideal hydrogen-rich membrane materials. The study, entitled \”Ultrathin, Molecular-Sieving Graphene Oxide Membranes for Selective Hydrogen Separation\” was published in the \”Science\” journal.
Original link: https: //science.sciencemag.org/content/342/6154/95 7.Nature: cationic plug
in Shanghai Institute of Applied Physics graphene oxide layer regulating selective separation FANG Haiping hospital, Shanghai University and Ye Li Jing Wu red team, Nanjing University Jin Wanqin team jointly found graphene oxide (GO) in an aromatic ring-containing group coexist and the region is easy to form a strong interaction with the ion-intercalating ions fixed to the site can be achieved accuracy of 1 Å layer spacing stable regulation, thus realizing highly efficient and rapid blocking various ion selective permeation of water. The study, entitled \”Ion sieving in membranes via grapheneoxide cationic control of interlayer spacing\” of papers published in \”Nature\” journal.
Original link: https: //www.nature.com/articles/nature24044 8.Nature Nanotechnology: single nanopores for desalination graphene film
Oak Ridge National Laboratory Shannon M . Mahurin Professor team thickness nanoporous graphene film having a mono-atomic chemical and mechanical stability of the preparation using an oxygen plasma etching process, such a porous graphene film excellent in water permeation rate (106g m-2s-1) and efficient ion rejection rate (nearly 100%), showed a desalination of great potential. The study, entitled \”Water desalination usingnanoporous single-layer graphene \”a paper published in the\” Nature Nanotechnology \”journal
Original link:. https: //www.nature.com/articles/nnano.2015.37 9.Nature Nanotechnology: multi-layer graphene low pressure modulation based nano holes electrostatic ion diffusion membrane
Dan Li, Professor University of Melbourne team using TF layered graphene based nano pores of the membrane bound tunable nano channel, demonstrated ion diffusion constraint <2 nm of interface may be an electric double layer (EDL) is strongly regulated. studies have shown that large-scale production with precise engineering technology advances nanopore and atoms, and the channel circuit, the size reduction of the control-related field effect ion transport are likely to cause the logic and signal transmission equipment and facilities made possible the study, entitled \"Low-voltageelectrostatic modulation of ion diffusion through layered graphene-based nanoporousmembranes\" papers published in \"Nature Nanotechnology\" journal
original link:.. https: // www .nature.com / articles / s41565-018-0181-4 10.Nature Nanotechnology: ion selective tunable graphene oxide film
Prof. Rahul R. Nair Manchester University research team graphene oxide ( GO) film package in an epoxy resin film layer to control the spacing of GO (ion channel size). the results show that when a layer spacing of <when 10Å, the channel sub-nanometer sized smaller than the radius of the hydrated ion, the ion permeability is greatly suppression and water permeability is not significantly affected, therefore have great potential in the field of desalination. the study, entitled \"Tunable sieving of ionsusing graphene oxide membranes \"of papers published in the\" Nature Nanotechnology \"journal
Original link:. https: //www.nature.com/articles/nnano.2017.21 11.Nature Materials: hydrophobic groups to enhance MoS2 film stability of isolated
Prof. Damien Voiry Université Montpellier, France joint Task Force Chinese University of Hong Kong Polytechnic Nicolas Onofrio research group a hydrophobic group modified policy to increase the interlayer spacing of MoS2 coatings and stability in water , while showing small organic molecules and ions higher inhibition rate there is a high water permeability, the results indicate a hydrophobic group can be increased and the dimensional stability channel dimensions, MoS2 and weakening the interaction of water with the matrix, increased water slip length and transmission speed within the nanochannel the study, entitled \”Enhanced sieving fromexfoliated MoS2 membranes via covalent functionalization\” of papers published in \”Nature Materials\” journal
original link:. https: // www .nature.com / articles / s41563-019-0464-7 12.Nature Materials: a graphene oxide film of the organic solvent nanofiltration
Professor RR Nair University of Manchester United, Professor Yang Su research team will size GO large layer interposed between 10-20 um assembled ultrathin (8 nm) layered film GO (HLGO), studied the behavior of various solvents in HLGO transmission and separation of the different molecular weight species / retention performance. this study suggests that the presence of a solvent different transmission paths GO film of different thicknesses, by changing the channel structure and transport mechanism, the organic solvent may have a high permeability and excellent performance in the multilayer GO molecular cutoff film, in which the solvent need nanofiltration petrochemical and pharmaceutical field has important application value and potentialvalue. \”Ultrathin graphene-basedmembrane with precise molecular sieving and ultrafast solvent permeation\” of the paper published in the study entitled \”Nature Materials\” journal.
Original link: https: //www.nature.com/articles/nmat5025 13.Nature Nanotechnology: artificial, \”membrane\”, water / NaCl selective over 109
Manish Kumar, a professor at Penn State University RatulChowdhury joint University of Illinois team Professor Aleksei Aksimentiev team obtained monomolecular isolated communication channels having a three-dimensional structure by synthetically, reverse osmosis separation membrane phospholipid bilayer after preparation of the composite showing a high water transmission similar aquaporins ion selectivity and single channel can be transmitted within 1 second (3.7 ± 0.3) × 109 th of H2O, H2O / NaCl separation factor of up to 109. This is achieved by changing the internal passage of water molecules and the aggregation structure of the overall size effect due to the ion, which provides a new way for designing highly efficient desalination membranes. The research paper entitled \”Artificialwater channels enable fast and selective water permeation through water-wirenetworks\” published in \”Nature Nanotechnology\” journal
Original link: https: //www.nature.com/articles/s41565- 019-0586-8 [IV. Nano fluidics water – Effect of Energy Technology]
nano fluidics water – Effect of energy technologies can be divided into two parts, the first is the efficient desalination of seawater using a special transmission behavior within the nanochannel, thePart of the three] [section has introduced in detail; the other is the use of selective ion transport in the efficient nanochannel having a concentration difference between sea water – fresh water generating electric power, i.e. osmotic – efficient energy between conversion. Here we have selected three research literature to nano-fluidics in water – energy technologies are introduced briefly.
1.Nature monolayer MoS2 nanoporous films can achieve significant penetration – the power converter
monolayer MoS2 porous films having different pore sizes EPFL Professor Aleksandra Radenovic TF prepared, since the Mo atoms hydrophilic and negatively charged pore surface properties, having a density difference bis KCl solution tank, water / K + transport speed and greater selectivity monolayer MoS2 porous separation membrane, osmotic – electrical energy conversion power density up to 106 W m-2, switching power density than conventional anti electrodialysis membrane obtained 100 times higher, under the title \”Single-layer MoS2 nanopores as nanopower\” published in \”Nature\” magazine.
Original link: https: //www.nature.com/articles/nature18593 2.Nature: single transmembrane BN nanotubes can penetrate – energy conversion
Professor University of Lyon, France Lyde\’ric Bocquet BN nanotubes found that the inner wall of the fluid TF (electrolyte) containing a large amount of contact with negative charges helps fast selective transport of ions; when the two can be realized between the electrolyte solution having a concentration difference groove BN nanotubes in larger osmotic – power conversion, by optimizing the diameter and the pH of the solution, to achieve maximum conversion power density 4 kW m-2. \”Giant osmotic energy conversion measuredin a single transmembrane boron nitride nanotube\” of the paper published in the study entitled \”Nature\” magazine.
Original link: https: //www.nature.com / articles / nature11876 3 Nature Nanotechnology:. synthetically prepared can be converted to Nanoporous permeation
Prof. Grégory F. Schneider Leiden University, The Netherlands Joint University of Ulm, Germany Ute Kaiser joint team has a core using – polycyclic aromatic hydrocarbon monomer molecules HPAHBC edge structure, after assembling the driving pressure – pyrolysis mode crosslinked prepared pore diameter of 3.6 ± 1.8nm, 0.5nm thickness of 2.0 ± carbon. More holes on the carbon film membrane pores -COO- electrically negatively, when the concentration difference among the highly electrolyte solution as a separator, having a high ion selectivity, thus showing excellent penetration properties can be converted, the output power up to 67 W m-2. The study, entitled \”Powergeneration by reverse electrodialysis in a single-layer nanoporous membranemade from core-rim polycyclic aromatic hydrocarbons\” of papers published in \”Nature Nanotechnology\” magazine.
Original link: https: //www.nature.com/articles/s41565-020-0641-5 [Summary: nano-fluidics future challenges]
nano-fluidics is a booming field it is not only the study of many fundamental problems of physics and chemistry, but also keep focus on water, energy and other issues concerning the development of mankind. However, as \”a man knows, the more feel that they know too little\” famous words pointed out, although in recent years has made nano-fluidics research more, but in many ways still are blank. So Professor Lydéric Bocquet pointed out that nano-fluidics in the future will face four major challenges:
(1) How to organic together in various disciplines in the study. Nano-fluidics is an interdisciplinary field of study, such as fluid dynamics, condensed matter, Statistical physics, chemistry, materials science, physiology, biology, etc., should be in the study of these disciplines together, with different points of view, in order to push forward the development of this field; (2) beyond \”simple nano-fluidics device design \”research methods. Fine nanochannel is the core of the device studies nanofluids, how to make full use of nano-fluidics principle in the design of complex structures even with the \”active\” nanochannel and propose new separation principle in the future for a long period of time is still the nano-fluidics research objectives focus; (3) the operation of looking at things at the nanometer scale. Currently, humans on the nano fluidics knowledge there are more blind spots, people need to develop new instruments and techniques to further characterize the specific mode of operation and observe how things are on the nanometer scale; application (4) nano-fluidics in the field of communication . While transfer speed of ions is slow, but they have many advantages over electronics, such as color and odor ion (different valence, size, etc. of lead polarization), if one can use these signals to complement the design of more efficient the information processor?