DE102004046109A1 - Nanostructures and coherent spatial structures for adsorbing chemicals (e.g. hydrogen in fuel cells) has all of its surfaces adapted for adsorption - Google Patents

Abstract

A nanostructure for adsorbing chemicals and having a maximal outer dimension of 2000 nm is such that each surface is an outer surface with a Gauss Curvature less than zero, is new. An independent claim is also included for a coherent spatial structure for adsorbing chemicals and having a curved surface with maximal radius of curvature of 1000 nm, the structure being an open-pored sponge structure with a number of surfaces merging into one another in the form of saddles with a Gauss Curvature less than zero.

Description

The The invention relates to a nanostructure for adsorbing chemical Substances according to the preamble of patent claim 1.

One example for the use of such a nanostructure consists in a hydrogen storage, in the hydrogen reversible to a variety of individual nanostructures is attached. There are many other applications as well such nanostructures for Adsorbing chemical substances, and in particular the cases here are of interest in which it is a reversible Adsorbieren the chemical substances, that is to say the temporary and detachable connection of the chemical substances to the respective nanostructure. There is but also useful applications where the connection is essentially should be permanent, for example, if certain substances to be filtered out of a gas stream.

STATE OF TECHNOLOGY

The Future of fuel cell technology, for example in the automotive sector, depends on Progress in the storage of hydrogen in hydrogen storage with as possible low volume, if possible low weight but still possible high reliability.

The Simple storage of hydrogen in pressure tanks holds a high Danger potential, here for a significant filling pressures in the range of 500 to 1,000 bar are necessary. Besides, they are corresponding pressure tanks bulky and heavy and therefore difficult to accommodate in motor vehicles.

One known alternative to hydrogen storage pressure tanks is based on porous solid bodies of metals. These hydrogen storage systems are based on the effect that certain metals, such as palladium or magnesium, and intermetallic compounds, such as ZrMn ₂ , absorb hydrogen under moderate pressure and bind it within their lattice structure as metal hydride. When the temperature increases, the hydrogen is released again. These chemical reactions are not only reversible but easy to control and allow a largely lossless storage of hydrogen over a longer period of time, since the gas is chemically bonded and therefore can not escape. Also from a safety point of view metal hydride storage is almost harmless. However, the disadvantage is the low mass-specific storage density of known metal hydride storage, which is only between 1.7 and 5 percent by weight of hydrogen, based on the mass of the storage medium. Metal hydride storage is very difficult. An additional disadvantage is that depending on the metal hydride to release the hydrogen very high temperatures are required. The previously achieved maximum storage density of 5 percent by weight was achieved with the aid of complex metal hydrides, such as sodium aluminum hydride (sodium allanate) in which, despite reducing kinetic barriers with suitable catalysts very long loading times are required and only relatively low Wiederabgaberaten of hydrogen can be realized.

It is therefore reinforced looking for alternative hydrogen storage. A high potential in this regard have nanostructures, i. nanoscale material structures, the principal due to their enlarged surface Offer advantages in the absorption of chemical substances. Also the Accessibility of the surface of nanostructures is compared with the accessibility of absorption sites in the Inside of a solid attractively priced.

In Recent years have reports of high storage capacities of Nanostructures in the form of carbon tubes with a diameter of up to 20 nanometers and a length of 100 nm up to a few Millimeters, attracted a lot of attention. The initially published However, high storage densities could not be detected experimentally become. Serious Storage densities are between 2 and 4.5% by weight, However, it is still unclear which sizes and other parameters of Carbon tubes have the best storage properties. So the walls of the tubes can be different Structures, i. Arrangements of the individual atoms, which have for example, as "armchair", "zigzag" and "chiral". The necessary loading times for carbon tubes to those specified above Storage densities are still in the range of some Hours and therefore tend to be too long for one To be used, for example, in the field of motor vehicles, in which a faster recharging of a hydrogen storage be possible should.

Curved and helical collimator tubes have also been considered as nanostructures to store hydrogen. As a result, but the basic characteristics of such Can not improve carbon tubes for hydrogen storage.

Next Carbon tubes are also nanostructures in the form of hollow spheres and arranged one inside the other Ball cups (nano onions) for hydrogen storage has been considered. In this However, the nestability worsens increasingly the reachability the then interior surfaces.

The Accessibility of the surfaces for the to be attached hydrogen is in a known nanostructure with the features of the preamble of claim 1 largest, the is called Nanocone and it is a cone-shaped structure is. However, the question is whether, e.g. Hydrogen too can attach to the inner tip of a nanocone, or whether here not actually very unfavorable potential conditions especially for the reversible attachment of chemical substances are present.

It are also planar graphitic carbon layers for storage Hydrogen has been tested. Even at relatively high pressures during the Loading, however, were only relatively low storage densities achieved.

In Terrones, H. et al .: "Curved nanostructured materials "in New J. Phys. 5 (2003) 126, PII: S1367-2630 (03) 65766-6 are various curved Nanostructures in principle described and ways for their production shown.

TASK OF THE INVENTION

Of the Invention is based on the object, a nanostructure for adsorbing chemical substances having the features of the preamble of the claim 1 show, in which all surfaces for the chemical to be adsorbed Substance easily accessible are.

SOLUTION

The The object of the invention is a nanostructure with the features of claim 1. Preferred embodiments The novel nanostructure are described in the other claims 2 to 10. The dependent claim 11 describes a bulk material consisting of a variety of such nanostructures and the dependent claim 12 a hydrogen storage with a variety of such nanostructures.

DESCRIPTION THE INVENTION

The therefor the adsorption of chemical substances proposed new nanostructure is characterized by the fact that at maximum dimensions of the nanostructure from 2000 nm every surface the nanostructure with an outer surface a Gaussian curvature less than zero. The requirement for exclusively external surfaces includes internal ones Surfaces, which is difficult to reach from the chemical substance to be adsorbed are, such as the inner surface of a hollow sphere, basically. The Gaussian curvature less than zero is an extra Demand that an additional Criterion for the good accessibility all surfaces the nanostructure. Which concrete nanostructures these Satisfy conditions, will be demonstrated below with reference to exemplary embodiments.

The new nanostructure has typical dimensions in the range of some tens of nanometers to several hundred nanometers, so their maximum Dimensions usually do not exceed 1000 nm. The usual number The atoms involved in the new nanostructure are between about 50 and a few hundred.

Prefers are nanostructures in which each surface has a minimum radius of curvature more than 1 nanometer, more preferably more than 10 nm. This ensures that there are no areas of the surfaces of the There are nanostructures in which potential barriers can be identified by the geometric shape of the surface build up adsorbing the chemical substances in this Exclude area in fact or at least the reversibility prevent adsorption.

The new nanostructures are preferably formed from an atomic single layer. atomic Multiple layers tend to only increase the weight and intrinsic volume of the nanostructure without improving their adsorptive properties with respect to the chemical substance.

The individual atoms of the atomic single bearings can be carbon atoms. The new nanostructures can but also of other substances, such as zeolites, i. Silicate minerals, Boron nitrides or organometallic complexes. The selection of the Material is in the individual case depending on the adsorbed to meet chemical substance.

In a concrete embodiment is the new nanostructure a so-called Möbius strip. Möbius bands are in different embodiments known. Nanoscale Möbius bands were by Ajami, D. et al: "Synthesis of a Mobius aromatic hydrocarbons "in Nature, Dec. 2003, Vol. 426, no. 6968, p. 819-821, presented.

Around preferably size minimum radii of curvature at the Möbius strip To realize, it is preferable if the Möbius strip just turned is. In this case, the Möbius strip as with any odd number of spins, only a single one surface on, which is accordingly particularly well accessible from the outside.

A other specific embodiment The new nanostructure has the form of a saddle, wherein this term here on the mathematical-geometric definition refers. An example for Such a saddle is a hyperbolic paraboloid.

Prefers however, such saddles are where each surface of the nanostructure is a minimum surface area and a mean curvature from zero. Such saddle, which are Ennepersche minimal surfaces can act have different symmetry parameters. Especially preferred is a symmetry parameter of at least two, because this is the Stackability of the nanostructures prevents and thus the danger eliminates that in a stack of individual nanostructures surfaces the inner nanostructures in the stack are difficult to access.

One another concrete example of the new nanostructure has the shape of a helicoid. Also at one Helicoid is any surface the nanostructure a minimal surface and has a mean curvature from zero, so that they are Enneper minimal surfaces. In a helicoid there is basically no stackability, but a certain danger of the radial meshing of individual Helicoids.

Also the fabrication of new nanostructures is by the fact facilitates that each of their surfaces is a minimal surface. This is tantamount to saying that the nanostructure is a geometric shape having minimal strain energy, i. is energetically stable. The new nanostructures can therefore For example, be prepared by a flat starting structure, such as a hexagonal array of graphitic carbon is deformed by placing at defined points by storage from foreign atoms tensions are introduced. In the endeavor the structure to reduce these tensions, the desired curved Nanostructures then almost automatically.

The new nanostructures in the form of a bulk material consisting of a variety of individual nanostructures used become. For example, a hydrogen storage can be formed become. The nanostructures can but also as a carrier for medicines, Catalysts and the like. Used or for capturing and holding, i. Render harmless, of chemical substances, for example from a gas stream. there In the case of the present application, it is primarily about the basic shape the nanostructures and the good accessibility of all surfaces of these Nanostructures.

SUMMARY THE FIGURES

in the The invention is described below with reference to the figures preferred embodiments further explained and described.

1 shows the course of the potential energy according to Lennard-Jones.

2 shows a nanostructure in the form of a simply rotated Möbius strip without kinks or with n → ∞, where n is the number of kinks.

3 shows a nanostructure in the form of a simply turned Möbius strip with a kink or with n = 3.

4 shows a nanostructure in the form of a simply twisted Möbius strip with a kink or with n = 4.

5 shows a nanostructure in the form of a simply twisted Möbius strip with a kink or with n = 6.

6 shows a nanostructure in the form of a saddle with the symmetry parameter s = 1.

7 shows a nanostructure in the form of a saddle with the symmetry parameter s = 2.

8th shows a nanostructure in the form of a saddle with the symmetry parameter s = 3.

9 shows a nanostructure in the form of a saddle, which has the shape of a hyperbolic paraboloid.

10 shows a nanostructure in the form of a helicoid.

11 shows the conversion of a catenoid to a helicoid; and the.

12 to 16 show nanostructures that are modifications of the helicoid according to 10 is.

DESCRIPTION OF THE FIGURES

introduction

mit den empirischen Größen ε (Tiefe der Potenzialmulde) und σ (Kollisionsabstand) bewährt. Der Vorteil dieser vereinfachenden Darstellung ist die Möglichkeit, das Wechselwirkungspotenzial für eine Mischung von Teilchen zu verallgemeinern. Während der erste Term in der linken Klammer die Abstoßung zwischen den abgeschlossenen Elektronenhüllen der Teilchen wiedergibt, beschreibt der zweite Ausdruck die Anziehung auf Grund der zwischenmolekularen Kräfte. Das Minimum der potenziellen Energie (Potenzialmulde) liegt bei diesem Modell stets bei

To describe the physical adsorption of gases on solid surfaces, the empirical interaction potential according to Lennard-Jones has been determined according to

proven with the empirical quantities ε (depth of potential well) and σ (collision distance). The advantage of this simplistic representation is the ability to generalize the interaction potential for a mixture of particles. While the first term in the left bracket represents the repulsion between the closed electron shells of the particles, the second term describes the attraction due to the intermolecular forces. The minimum of potential energy (potential well) is always included with this model

This Equilibrium state is thus at a distance that just a little bigger than the collision distance is.

Quality Solutions of the Hydrogen storage problems should therefore be the fundamental and allow quick access to the potential well. Because the attractive forces correspond to the negative gradient of the potential field, however even with values r / σ> 2 negligible becomes small, nanostructures had to be found, from which none unnecessary Potential barriers for the hydrogen result.

• 1. Die Kohlenstoffatome werden derart angeordnet, dass ihre Modifikation eine maximale Oberfläche aufweist und gleichzeitig die Kohlenstoffmenge minimiert. Diese Maßnahme führt zwangsläufig zu einer Gewichtsersparnis und zu einer sehr effizienten Speicherfähigkeit.
• 2. Die Kohlenstoffatome werden derart angeordnet, dass sich die Oberflächen der Molekülstrukturen nicht gegenseitig abdecken (wie z.B. bei Multi-Wall CNT) und der Wasserstoff durch die entstehende Potenzialbarriere nur unter Aufwendung zusätzlicher Energien und Kräfte (z.B. durch höhere Drücke) die inneren Flächen erreichen kann. Diese Maßnahme sollte zu einer Maximierung an „verfügbaren" Oberflächen und zu kurzen Beladungszeiten führen.

The nanostructures described below take this requirement into account, with the aim of providing the greatest possible number of "docking points" for the hydrogen, which can basically be achieved by two measures:

• 1. The carbon atoms are arranged so that their modification has a maximum surface area while minimizing the amount of carbon. This measure inevitably leads to weight savings and to a very efficient storage capacity.
• 2. The carbon atoms are arranged so that the surfaces of the molecular structures are not cover each other (as with multi-wall CNT) and the hydrogen can reach the inner surfaces only by using additional energy and forces (eg by higher pressures) through the resulting potential barrier. This measure should lead to a maximization of "available" surfaces and to short loading times.

nanostructure in the form of a Möbius strip

One embodiment of the novel nanostructure for adsorbing chemical substances that meet the above requirements are nanoscale Möbius ribbons, which are also referred to herein as nanotapes, and which are referred to in US Pat 2 to 5 are reproduced.

mit den Parameterintervallen s ∊ [–w; w] und t ∊ [0; 2π] lautet. Die halbe Breite ist w und der Radius R. Durch eine einfache Drehung (Twist) der gekrümmten Fläche ist sie nunmehr einseitig. Das Nanotape ist daher ein Spezialfall einer nichtorientierbaren Fläche, auf der es einen einfach geschlossenen Weg gibt, längs dem sich das topologische Bild eines Kreises so verschieben lässt, dass es mit umgekehrter Orientierung an seinen Ausgangspunkt zurückkehrt. Dabei besitzt das Nano-Tape die Gaußsche und die mittlere Krümmung

These are curved surfaces in the differential geometric sense, their parameter form

with the parameter intervals s ε [-w; w] and t ε [0; 2π] reads. The half width is w and the radius is R. By a simple twist of the curved surface, it is now one-sided. The nanotape is therefore a special case of a non-orientable surface on which there is a simply closed path along which the topological image of a circle can be shifted so that it returns to its starting point in the opposite direction. The nano-tape has the Gaussian and the mean curvature

The hydrogen atoms are therefore well able to attach themselves to the carbon. A twofold rotation of the nano-tape is not recommended for hydrogen storage, as it has geometric potential barriers. The in the 3 to 5 The "angular" variants shown show the greater the radii of curvature, the more the number of corners n approaches infinity (cf. 2 ) and the nanostructure is converted into the geometry of an ideal Möbiusbands. The important parameters for optimizing the storage density are the radius of the nanotape and the width of the tape.

im Intervall t ∊ [0; 4π].The Möbius strip has the surface element

in the interval t ε [0; 4π].

The surface element of the Möbius strip itself preferably consists of a deformed hexagonal arrangement of graphitic carbon, but may also be of other suitable Substances exist, e.g. of zeolites (silicate minerals), boron nitride or from MOF's. The deformation of the basic arrangement can by selective installation controlled by Frematomen.

By the Möbius band arrangement only "outer" surfaces exist which are the hydrogen molecules can accumulate so densely packed, that the used surface becomes larger per volume. in the Compared to graphite therefore offers a system of nano-tapes one much larger number from places to "dock" other atoms or molecular fragments to the carbon atoms and thus many possibilities, chemical bonds to socialize.

there It is foreseeable that the width and length of the nanotapes are crucial Parameters in the identification of the optimal configuration, e.g. for the Hydrogen storage, are. In this case, e.g. the length like that be interpreted that they are in a system consisting of a variety of tapes (particle system), not too large, so that at a mesh the surfaces the attachment possibilities for the hydrogen stay big enough.

The Production of stable nanoscale Möbius bands has already been reported in Ajami, D. et al .: "Synthesis of a Mobius aromatic hydrocarbon ", Nature, Dec. 2003, Vol 426, no. 6968, pp. 819-821. These The chemical preparation described was based on annulenes (unbridged aromatics with 14 or 18 π electrons).

nanostructure in the form of a saddle

Another embodiment of the novel nanostructure for adsorbing chemical substances that meet the above requirements are nano-scale saddles, also referred to herein as nano saddles, which are incorporated in the 6 to 9 are reproduced.

lautet. Es handel sich hierbei um Ennepersche Minimalflächen, deren Symmetrieparameter s ist. Bei dem in 7 für s = 2 dargestellten Nanosattel haben die krummlinigen Parameter u und v beispielsweise die Werte u ∊ [0, 1.2], v ∊[–π, π] Nano saddles are minimal surfaces in the differential geometric sense whose average curvature disappears and their parameter shape

reads. These are Enneper minimal surfaces whose symmetry parameter is s. At the in 7 For nano saddles shown for s = 2, the curvilinear parameters u and v have the values, for example u ∈ [0, 1.2], v ε [-π, π]

The parameter v provides the completeness of the area from the center. The parameter u defines the inner and outer edges of the surface. With u _min = 0 there is no central hole. Otherwise they are stripes on the minimal surface of Enneper.

Further variants of the nanostructure in the form of a saddle result from the consideration of hyperbolic paraboloids (cf. 9 ), which in contrast to Enneper 's minimal surfaces have straight edges and those of parametrization x (u, v) = a · (u - v) y (u, v) = b · (u + v) z (u, v) = u · v to obey. Design parameters here are the scaling variables a and b.

The implicit form of nano saddle is

mit der komplexen Variablen z := r·ej·ϕ,der analytischen Funktion f

und der meromorphen Funktion gThe geometry of the nano saddle can also be represented by the Weierstrass parameterization:

with the complex variable z: = r · e j · φ . the analytic function f

and the meromorphic function g

With the value ranges r ε [0, 1] and φ ε [-π, π] the representation is consequently

Will the complex variable according to z: = α + j · β with the straight-line parameters α (real part, eg α ε [-1, 1]) and β (imaginary part, eg β ε [-1, 1]) substituted, the nano saddles obey the representation

die stets negative Gaußsche Krümmung

und die mittlere Krümmung H = 12 (κ1 + κ2) = 0. The nano saddles according to the invention have the main curvatures

the always negative Gaussian curvature

and the mean curvature H = 1 2 (κ 1 + κ 2 ) = 0.

A differential surface element of the nano saddle is through dA = (1 + α 2 + β 2 ) dα ∧ dβ given. The value ranges α ε [α _min , α _max ] β ε [β _min , β _max ] result in the (one-sided) surface area

These area is the hydrogen (at least one side) for "docking" available.

The nano saddles therefore fulfill the d'Alembert differential equation as minimal surfaces y = x · f (y ') + g (y') with the given functions f and g or the Lagrangian differential equation (1 + f v 2 ) · F uu + 2 · f u f v f uv + (1 + f u 2 ) f vv = 0.

The Nanosattel can therefore also as an area be characterized, which is a special solution for given boundary conditions is (plateau problem).

In the nanostructure for adsorbing chemical substances in the form of a saddle, only open surfaces that are easily accessible to the hydrogen atoms are realized, which do not intersect each other as long as the design parameter μ remains small enough. The mean curvature is zero, which ultimately suggests a low power-to-weight ratio. If the integer symmetry parameter s = 1 (cf. 6 ), the minimal surface takes on a shape in which several nanostructures can cover each other, similar to so-called "crisps" in their packaging. Consequently, undesirable potential barriers with regard to the addition of hydrogen to the carbon atoms are to be expected for this case. For all symmetry values s ≥ 2 (compare the 7 and 8th ), however, the surfaces of the individual components can no longer cover each other.

Also the nano saddle according to the invention exist in the area preferably of a (deformed) hexagonal arrangement of graphitic carbon; you can but also on other suitable substances, e.g. on zeolites (Silicate minerals), boron nitride or from MOF's.

nanostructure in the form of a helicoid

Another embodiment of the novel nanostructure for adsorbing chemical substances that meet the above requirements are nanoscale helicides, also referred to herein as nanohelicides, and for which an example is given in US Pat 10 is reproduced.

Nanohelikoids are minimal surfaces in the differential geometric sense, their parameter form x (u, v) = sin (n · u) · sinh (v) y (u, v) = cos (n · u) · sinh (v) z (u) = m · u reads. At the in 10 Nanohelikoiden shown have the parameters u and v, for example, the values u ε [0, 4π], v ε [-1, 1] with n = m = 1.

The parameter v provides the diameter of the winding and its symmetry or uniformity (see below) 12 to 16 ). The parameter u can be used to set the number of turns. With the help of n and m, the pitch can be adjusted.

As 11 outlined, a helicoid minimal surface emerges by conjunction of a catenoid, which is also well known from soap bubble experiments, according to x (u, v) = cos (α) * cos (u) * cosh (v) + sin (α) * sin (u) * sinh (v) y (u, v) = -cos (α) · sin (u) · cosh (v) + sin (α) · cos (u) · sinh (v) z (u, v) = cos (α) · v + sin (α) · u (Catenoid: α = 0, helicoid: α = π / 2).

In cylindrical coordinates, a helically extending line on the helical surface obeys the equation: z = c · δ with the constant c. In Cartesian coordinates, the line obeys the equation y x = tan ( z c ).

With the value ranges u ε [0, δ] and v ε [0, r], the lines generate the minimum area with the (one-sided) area

die stets negative Gaußsche Krümmung

und die mittlere Krümmung H = 12 (κ1 + κ2) = 0. This surface has the main curvatures

the always negative Gaussian curvature

and the mean curvature H = 1 2 (κ 1 + κ 2 ) = 0.

The proposed nanohelicides therefore fulfill the d'Alembert differential equation as minimal surfaces y = x · f (y ') + g (y') with the given functions f and g or the Lagrangian differential equation (1 + f v 2 ) f uu + 2 · f u f v f uv + (1 + f u 2 ) · Fvv = 0.

The Nanohelikoids can therefore also as an area be characterized, which is a special solution for given boundary conditions is (plateau problem).

The helical surface the nanohelicides according to the invention preferably consists of a (deformed) hexagonal arrangement graphitic carbon, but it can also be used on other suitable Build up substances, e.g. on zeolites (silicate minerals), boron nitride or from MOF's.

By In the case of nanohelikoids, the helical structure has only "outer" surfaces which are the hydrogen molecules can accumulate so densely packed, that the used surface is particularly large per volume. Compared to layered graphite therefore offers a Nanohelikoids system a much larger number of places to "dock" other atoms or molecular fragments to the carbon atoms and thus many possibilities, chemical bonds to socialize.

It is understandable that the pitch, the length and the radii of the helicoid the key parameters in identifying the optimal Configuration, e.g. For the hydrogen storage, are. In this case, e.g. the pitch in such a way to interpret that when interlocking the surfaces, the possibility of attachment of hydrogen remains sufficiently large.

moreover are electrochemical activation of the helicidene according to the invention Carbon modification highly resilient actuators can be formed.

As possible modifications of nanohelikoids according to 10 those are mentioned which result from variation of form-relevant parameters. However, the variation may result in the loss of the minimum surface property. With regard to the hydrogen storage capacity, a good but suboptimal performance is still to be expected.

12 shows a nanostructure in which the parameters v and u defined above assume the values v = [-1, 2] and u = [0.4 · Pi].

13 shows a nanostructure in which the parameters v and u defined above assume the values v = [-1, 1] and u = [0.8 · Pi].

14 shows a nanostructure in which the parameters v and u defined above assume the values v = [-0, 1] and u = [0.4 · Pi].

15 shows a nanostructure in which the equations X = sinh (v) · sin (u) · u Y = sinh (v) · cos (u) · u Z = u V = [-1, 1] and u = [0.4 · Pi] are fulfilled.

16 shows a nanostructure in which the equations X = sinh (v) · sin (u) · u ^ 2 Y = sinh (v) · cos (u) · u ^ 2 Z = u v = [-1, 1] and u = [0.4 · Pi] are fulfilled.

• – Medikamentwirkstoffe zu transportieren oder
• – Chemikalien zu binden bzw. chemische Reaktivitäten herabzusetzen oder
• – Katalysatoren zu miniaturisieren.

Due to their special physical and chemical properties, which are due to their geometric shape, the storage of hydrogen and other gaseous substances, as well as the possibilities of the new nanostructure

• - to transport drug substances or
• - to bind chemicals or reduce chemical reactivities or
• - miniaturizing catalysts.

Claims (12)

Nanostructure for adsorbing chemical substances having a maximum outer dimension of 2000 nm and having at least one curved outer surface, characterized in that each surface of the nanostructure is an outer surface having a Gaussian curvature of less than zero. Nanostructure according to claim 1, characterized in that that every surface the nanostructure has a minimum radius of curvature of more than 1 nm, preferably more than 10 nm. Nanostructure according to claim 1 or 2, characterized that it is formed from an atomic single layer. Nanostructure according to one of Claims 1 to 3, characterized that they are in the shape of a Möbius strip having. Nanostructure according to Claim 4, characterized that the Möbius strip just turned. Nanostructure according to one of Claims 1 to 3, characterized that it has the shape of a saddle. Nanostructure according to one of claims 1 to 3 and 6, characterized characterized in that each surface of the Nanostructure a minimal area is. Nanostructure according to Claim 7, characterized that every surface the nanostructure has a mean curvature of zero. Nanostructure according to claim 7 or 8, characterized that it has the form of a helicoid. Nanostructure according to one of claims 1 to 9, characterized in that it is not stackable. bulk existing from a variety of nanostructures according to one of claims 1 to 10. Hydrogen storage with a variety of nanostructures according to one of the claims 1 to 10.