Device suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance apparatus

Abstract

A device is provided that is suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance device. The device contains a hollow base body, two caps that can be connected or are connected to a respective end of the hollow base body via a reversible and fluid-tight connection, and two flat walls that extend parallel to a longitudinal axis of the hollow base body in the interior of the hollow base body, each extending from one end of the hollow base body toward a center of the hollow base body. The device can be manufactured cost-effectively, is suitable for placement in a nuclear magnetic resonance device, and allows an in-situ / operando investigation of an electrochemical reaction via nuclear magnetic resonance in a nuclear magnetic resonance device.The device makes it possible to measure an electrochemical reaction in a nuclear magnetic resonance device in a more cost-effective, reproducible, accurate and rapid manner.

Description

[0001] A device is provided that is suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance device. The device contains a hollow base body, two caps that can be connected or are connected to a respective end of the hollow base body via a reversible and fluid-tight connection, and two flat walls that extend parallel to a longitudinal axis of the hollow base body in the interior of the hollow base body, each extending from one end of the hollow base body toward a center of the hollow base body. The device can be manufactured cost-effectively, is suitable for placement in a nuclear magnetic resonance device, and allows an in-situ / operando investigation of an electrochemical reaction via nuclear magnetic resonance in a nuclear magnetic resonance device.The device makes it possible to measure an electrochemical reaction in a nuclear magnetic resonance device in a more cost-effective, reproducible, accurate and rapid manner.

[0002] Various devices are known in the prior art that are suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance device.

[0003] For example, so-called pouch cells are known for this purpose (see, for example, Richter, JB et al., Chem. Comm., 2019, 55:6042-6045). These cells are relatively soft and flexible devices made of a thin plastic film (e.g., polyethylene). In these cells, the electrodes, the separator, and the analyte are welded into the thin plastic film before an electrochemical reaction is carried out and measured in a nuclear magnetic resonance device. However, the lack of dimensional stability of pouch cells makes reproducibility difficult with regard to cell geometry, which can play an important role in electrochemical processes (electrode spacing, electrode area, electrode geometry, etc.). Furthermore, contact between the electrodes inside the pouch cells is made via metal wires or metal wire mesh, which are not always chemically inert, which can lead to undesirable side reactions.Furthermore, manually welding the cells is error-prone and can often lead to leaks, which makes accurate and reproducible measurements difficult. The soft nature of pouch cells also makes it difficult to install a reference electrode, without which a defined electrical potential cannot be established. Furthermore, pouch cells are unsuitable when gases are involved in the electrochemical reaction being investigated, as the cell body of the pouch cells can then rupture.

[0004] So-called Swagelok cells are also known in the prior art (see, for example, Durajski, AP et al., Acta Physica Polonica A, 2020, 138(2):148-151). These cells are solid devices made of plastic (e.g., PTFE) or glass, which overcome some of the disadvantages of pouch cells. However, Swagelok cells have the disadvantage that they are often more expensive to manufacture (e.g., if they are made of PTFE) and often require additional seals to deliver accurate and reproducible results. Swagelok cells generally do not provide the option of incorporating a reference electrode. Furthermore, Swagelok cells have the disadvantage that the area in which the electrodes are in contact with a voltage source lies within the measuring range, which can distort the measured results, i.e., make them inaccurate.Furthermore, the arrangement of the electrodes in Swagelok cells prevents them from being used as flow cells (i.e., the flow of electrolyte is prevented by the electrode arrangement). Furthermore, the electrode area in Swagelok cells is limited by their diameter, which limits the maximum possible material conversion in electrochemical reactions and can result in long measurement times.

[0005] Based on this, the object of the present invention was to provide a device suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance device and which overcomes at least one disadvantage of the devices known in the prior art. In particular, the device should make it possible to measure an electrochemical reaction (which can in particular also be a gas-releasing electrochemical reaction) in a nuclear magnetic resonance device in a more cost-effective, reproducible, accurate, and rapid manner.

[0006] The object is achieved by the device having the features of claim 1. The dependent claims show advantageous developments.

[0007] According to the invention, a device is provided which is suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance apparatus, containing or consisting of: a) a hollow base body having an interior space, the hollow base body having a shape of a right circular cylinder at a first end along a longitudinal axis of the hollow base body and a shape of a right circular cylinder at a second end opposite the first end; b) a first cap which is connectable or connected to the first end of the hollow base body via a reversible, fluid-tight connection, wherein the first cap has, at least in regions along a surface extending perpendicular to the longitudinal axis of the hollow base body, a first septum which contacts a wall of the first cap; c) a second cap which is connectable or connected to the second end of the hollow base body via a reversible, fluid-tight connection, and wherein the second cap has, at least in regions along a surface extending perpendicular to the longitudinal axis of the hollow base body, a second septum which contacts a wall of the second cap; d) a first flat wall having a top side and a bottom side and being suitable for arranging a working electrode on the top side thereof and a counter electrode on the bottom side thereof, wherein the first flat wall is arranged in the interior of the hollow base body and is connected to an inner wall of the hollow base body via an irreversible connection, wherein the first flat wall is arranged parallel to the longitudinal axis of the hollow base body and extends from the first end of the hollow base body towards a center of the hollow base body; e) a second flat wall having a top side and a bottom side and being suitable for arranging a working electrode on the top side thereof and a counter electrode on the bottom side thereof, wherein the second flat wall is arranged in the interior of the hollow base body and is connected to an inner wall of the hollow base body via an irreversible connection, wherein the second flat wall is arranged parallel to the longitudinal axis of the hollow base body and extends from the second end of the base body towards a center of the hollow base body.

[0008] With the device according to the invention, it is possible to measure an electrochemical reaction (in particular a gas-releasing electrochemical reaction) in a nuclear magnetic resonance device in a more cost-effective, reproducible, accurate and rapid manner.

[0009] The low costs result from the fact that the device can be manufactured from inexpensive materials.

[0010] The more reproducible and more accurate measurement by the device results from the fact that the device - unlike pouch cells - has a stable shape, i.e. because the base body has the shape of a circular cylinder at least in some areas and the flat walls are firmly connected to the stable base body as a support surface for the two electrodes.

[0011] Furthermore, the device results in more precise and faster measurements because the device's electrodes - unlike Swagelok cells - are arranged along the longitudinal axis of the at least partially cylindrical base body and not perpendicular to the longitudinal axis. This means that the electrically conductive contact points of the electrodes to an electrical voltage source can be located outside the measuring range, and any distortion of the measurement by the electrical contact points can be ruled out. In addition, the total surface area of ​​the electrodes can be larger than with an arrangement of the electrodes perpendicular to the longitudinal axis (as in Swagelok cells), which allows higher material conversions per unit time to be achieved and thus can shorten the measurement time.

[0012] Apart from that, the device according to the invention allows the use of the device as a flow cell by arranging the electrodes along the longitudinal axis, for example by inserting a cannula into the respective septum of the first cap and second cap and establishing a fluid-conducting connection to a source of electrolyte.

[0013] The device according to the invention can (already) contain a flat working electrode with a top side and a bottom side, wherein the bottom side of the flat working electrode is arranged on the top side of the first flat wall and on the top side of the second flat wall.

[0014] The flat working electrode may contain or consist of carbon, wherein the flat working electrode preferably contains or consists of a carbon paper and / or a carbon fabric.

[0015] Furthermore, the flat working electrode can have, along a longitudinal axis of the hollow base body, an extension (i.e., a length) in the range of 50 to 95%, preferably 60 to 90%, particularly preferably 70 to 85%, of the extension of the hollow base body along its longitudinal axis, in particular an extension in the range of 15 to 25 mm. The longer this extension, the larger the area of ​​the flat working electrode and the shorter the measurement times.

[0016] In addition, the flat working electrode can have an extension (i.e., a width) perpendicular to a longitudinal axis of the hollow base body and parallel to a surface of the flat working electrode in the range of 18 to 33%, preferably 21 to 31%, particularly preferably 24 to 30%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension of 5 to 10 mm. The longer this extension, the larger the surface of the flat working electrode and the shorter the measurement times.

[0017] Apart from this, the flat working electrode can have, perpendicular to a longitudinal axis of the hollow base body and perpendicular to a surface of the flat working electrode, an extension (ie a thickness) in the range 1 to 10%, preferably 2 to 8%, particularly preferably 4 to 6%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension in the range of 0.10 to 0.75 mm.

[0018] The device according to the invention can (already) contain a planar counter electrode with a top side and a bottom side, wherein the bottom side of the planar counter electrode is arranged on the bottom side of the first planar wall and on the bottom side of the second planar wall.

[0019] The flat counter electrode may contain or consist of carbon, wherein the counter electrode preferably contains or consists of a carbon paper and / or a carbon fabric.

[0020] Furthermore, the flat counter electrode can have, along a longitudinal axis of the hollow base body, an extension (i.e., a length) in the range of 50 to 95%, preferably 60 to 90%, particularly preferably 70 to 75 to 85%, of the extension of the hollow base body along its longitudinal axis, in particular an extension in the range of 15 to 25 mm. The longer this extension, the larger the area of ​​the flat working electrode and the shorter the measurement times.

[0021] In addition, the flat counterelectrode can have an extension (i.e., a width) perpendicular to a longitudinal axis of the hollow base body and parallel to a surface of the flat counterelectrode in the range of 18 to 33%, preferably 21 to 31%, particularly preferably 24 to 30%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension of 5 to 10 mm. The longer this extension, the larger the surface of the flat working electrode and the shorter the measurement times.

[0022] Apart from this, the flat counter electrode can have, perpendicular to a longitudinal axis of the hollow base body and perpendicular to a surface of the flat counter electrode, an extension (ie a thickness) in the range 1 to 10%, preferably 2 to 8%, particularly preferably 4 to 6%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension of 0.10 to 0.75 mm.

[0023] The hollow base body may contain or consist of a material selected from the group consisting of plastic, glass, ceramic and combinations thereof, wherein the plastic is in particular selected from the group consisting of polyolefins and UV-curable plastics, wherein the plastic is optionally polypropylene.

[0024] In a particularly preferred embodiment, the hollow base body has no electrical conductivity. The advantage is that an electrical short circuit can be more reliably prevented from occurring during a measurement of an electrochemical reaction.

[0025] The hollow base body can be manufactured using 3D printing. The advantage of this is that the hollow base body can be produced quickly and cost-effectively.

[0026] Furthermore, the hollow base body can have an extension (i.e., a length) along its longitudinal axis in the range of 10 to 50 mm, preferably 20 to 40 mm, particularly preferably 25 to 30 mm. An extension in this range is particularly advantageous for a measurement in a nuclear magnetic resonance device.

[0027] In addition, the hollow base body can have an extension (i.e., a width) in the range of 8 to 14 mm, preferably 9 to 13 mm, particularly preferably 10 to 12 mm, at its first end and / or at its second end, perpendicular to its longitudinal axis. The advantage is that the device thus has a width that is particularly suitable for measurement in a nuclear magnetic resonance device.

[0028] The hollow base body can have a portion of its interior between its first end and its second end that, at least in part, has the shape of a square cone. The advantage of the square cone is that it creates a larger space within the hollow base body in which the electrochemical reaction can take place.

[0029] Furthermore, the hollow base body can have an extension (i.e., a width) in the range of >14 to 17 mm, preferably 14.5 to 16 mm, particularly preferably 15 to 15.5 mm, between its first end and its second end, perpendicular to its longitudinal axis. An extension in this range is particularly advantageous for a measurement in a nuclear magnetic resonance device.

[0030] In addition, the hollow base body can have a first bulge between its first end and its second end, which expands the interior in a direction perpendicular to the longitudinal axis of the hollow base body. The first bulge can have the shape of a hemisphere, at least in some regions. Furthermore, the first bulge can have an extension along a longitudinal axis of the hollow base body in the range of >25 to 45%, preferably 30 to 42%, particularly preferably 35 to 40%, of the extension of the hollow base body along its longitudinal axis. The advantage of the first bulge is that a space is created in the interior of the hollow base body in which gas can accumulate, which is released in an electrochemical reaction. The released gas can thus be collected in the interior of the hollow base body at this location.

[0031] Apart from that, the hollow base body can have a second bulge between its first end and its second end, which expands the interior in a direction perpendicular to the longitudinal axis of the hollow base body, wherein the second bulge preferably has the shape of a hemisphere at least in some regions and / or lies along a longitudinal axis of the hollow base body, having an extent in the range of 5 to 25%, preferably 10 to 22%, particularly preferably 15 to 20%, of the extent of the hollow base body along its longitudinal axis. The advantage of the second bulge is that it provides a space for the stable reception of an electrode (e.g. a reference electrode) in the interior of the hollow base body.

[0032] Furthermore, the hollow base body can have an opening between its first end and its second end, preferably at a first bulge of the hollow base body in this region. The opening has the advantage that, for example, at least one additional electrode (e.g., a reference electrode, an electrode for measuring a pH value, and / or an electrode for measuring a temperature) can be introduced into the interior of the device through the opening.

[0033] A third septum can be arranged in the opening and contacts a wall of the hollow base body. The third septum has the advantage that the opening is closed by the septum, but a component can still be introduced into the interior of the device by piercing the septum. The third septum particularly preferably contains or consists of a membrane. The membrane can contain or consist of an elastomeric plastic, wherein the elastomeric plastic is preferably natural rubber. Furthermore, the membrane can have a thickness, in a direction along the longitudinal axis of the hollow base body, in the range of 0.5 to 3 mm, preferably 0.75 to 2 mm, particularly preferably 1 to 1.5 mm.

[0034] The hollow base body can have a groove facing the interior of the hollow base body between its first end and its second end, preferably at a second bulge of the hollow base body in this region, which groove is suitable for receiving one end of an additional electrode (e.g., a reference electrode, an electrode for measuring a pH value, and / or an electrode for measuring a temperature). The advantage is that the additional electrode can be arranged more stably in the interior of the device by being accommodated in the groove.

[0035] The reversible, fluid-tight connection of the first cap to the first end of the hollow base body and / or the reversible, fluid-tight connection of the second cap to the second end of the hollow base body can be selected from the group consisting of force-locking connections, positive-locking connections, and combinations thereof. The reversible, fluid-tight connection is preferably a screw connection.

[0036] The first cap without its first septum and / or the second cap without its second septum may contain or consist of a plastic, wherein the plastic is preferably selected from the group consisting of polyolefins, wherein the plastic is particularly preferably polypropylene.

[0037] Furthermore, the first cap can be manufactured without its first septum and / or the second cap without its second septum using 3D printing. The advantage is that both caps can be manufactured without their respective septums in a simple and cost-effective manner.

[0038] Additionally, the first cap without its first septum and / or the second cap without its second septum can be an ND13 screw cap without a septum. The advantage is that said ND13 screw cap is available at a reasonable price.

[0039] The first septum of the first cap and / or the second septum of the second cap can contain or consist of a membrane. The membrane can contain or consist of an elastomeric plastic, wherein the elastomeric plastic is preferably natural rubber. Furthermore, the membrane can have a thickness, in a direction along the longitudinal axis of the hollow base body, in the range of 0.5 to 3 mm, preferably 0.75 to 2 mm, particularly preferably 1 to 1.5 mm. In addition, the membrane can be a septum that has an ND13 screw cap with a septum. The advantage of the septum of an ND13 screw cap is that it is inexpensive to obtain.

[0040] The first flat wall in the interior of the hollow base body and / or the second flat wall in the interior of the hollow base body can contain or consist of a material selected from the group consisting of plastic, glass, ceramic, and combinations thereof. The plastic is in particular selected from the group consisting of polyolefins and UV-curable plastics, wherein the plastic is optionally polypropylene.

[0041] Furthermore, the first flat wall in the interior of the hollow base body and / or the second flat wall in the interior of the hollow base body can be integral with the base body. This has the advantage of making the device very stable.

[0042] Furthermore, the first flat wall in the interior of the hollow base body and / or the second flat wall in the interior of the hollow base body can be manufactured using 3D printing, preferably together with the hollow base body. This has the advantage that the device can be manufactured in a simple and cost-effective manner.

[0043] Apart from this, the first flat wall in the interior of the hollow base body and / or the second flat wall in the interior of the hollow base body can, along a longitudinal axis of the hollow base body, have an extension (i.e., a length) in the range of 25 to 45%, preferably 30 to 42%, particularly preferably 35 to 40%, of the extension of the hollow base body along its longitudinal axis. This has the advantage that the flat wall provides a long support surface for the respective electrode, and thus the respective electrode is arranged more stably in the device.

[0044] Furthermore, the first flat wall in the interior of the hollow base body and / or the second flat wall in the interior of the hollow base body, perpendicular to a longitudinal axis of the hollow base body and parallel to a surface of the flat wall, can have an extension (i.e., a width) in the range of 1 to 10%, preferably 2 to 8%, particularly preferably 4 to 6%, of the extension of the hollow base body perpendicular to its longitudinal axis. This has the advantage that the flat wall provides a sufficiently wide support surface for the respective electrode, and thus the respective electrode is arranged more stably in the device.

[0045] The hollow base body can have a first wall in its interior for establishing contact with a lateral surface of a flat working electrode. The first wall extends at the second end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and is connected to an upper side of the second flat wall. The first wall is particularly preferably integral with the second flat wall. The first wall represents a lateral stop surface for the electrode and can ensure a more stable arrangement of the electrode within the device.

[0046] Furthermore, the hollow base body can have a second wall in its interior for establishing contact with a lateral surface of a planar counterelectrode. The second wall extends at the first end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and is connected to an underside of the first planar wall. The second wall is particularly preferably integral with the first planar wall. The second wall represents a lateral stop surface for the counterelectrode and can ensure a more stable arrangement of the counterelectrode within the device.

[0047] In addition, the hollow base body can have a third wall in its interior for establishing contact with an upper side of a planar working electrode, wherein the third wall extends at the first end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and has a distance from the first planar wall that essentially corresponds to a thickness of the planar working electrode in a direction perpendicular to the longitudinal axis of the hollow base body. The third wall represents an upper stop surface for the electrode and can ensure a more stable arrangement of the electrode within the device.

[0048] Furthermore, the hollow base body can have a fourth wall in its interior for establishing contact with an upper side of a planar counterelectrode, wherein the fourth wall extends at the second end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and is spaced from the second planar wall at a distance substantially corresponding to a thickness of the planar counterelectrode in a direction perpendicular to the longitudinal axis of the hollow base body. The fourth wall represents an upper stop surface for the counterelectrode and can ensure a more stable arrangement of the counterelectrode within the device.

[0049] The device may have an additional electrode.

[0050] The additional electrode may be selected from the group consisting of a reference electrode, an electrode for measuring a pH value, an electrode for measuring a temperature and combinations thereof.

[0051] Furthermore, the additional electrode can be rod-shaped, at least in some areas.

[0052] Furthermore, the additional electrode can contain or consist of a material selected from the group consisting of plastic, glass, ceramic, and combinations thereof. The plastic is preferably selected from the group consisting of polyolefins and fluorine-containing plastics, with the fluorine-containing plastic being, in particular, polytetrafluoroethylene.

[0053] Furthermore, the additional electrode can be arranged in a part of the interior of the hollow base body that is located between the first end and the second end of the hollow base body, preferably in a part of its interior that, at least in some regions, has the shape of an angular cone. The additional electrode is particularly preferably arranged substantially perpendicular to the longitudinal axis of the hollow base body, in particular arranged in an opening of the hollow base body. Preferably, the additional electrode is also arranged in a groove of the hollow base body. The additional electrode can pierce a third septum that is arranged in the opening of the hollow base body.

[0054] Apart from that, the additional electrode can have a length in the range of 15 to 40 mm.

[0055] The device may further comprise a first cannula that pierces the first septum of the cap and is preferably fluidly connected to an electrolyte source. This allows electrolyte to be supplied to the interior of the device via the first cannula.

[0056] The device may further comprise a second cannula that pierces the second septum of the cap and is preferably fluidically connected to an electrolyte sink. This allows electrolyte to be drained from the interior of the device. It is thus also possible to use the device as a flow cell. The electrolyte sink is optionally an electrolyte source that is fluidically connected to a first cannula of the device that pierces the first septum of the cap. In this case, an electrolyte can be circulated within the interior of the device.

[0057] The device may further include a first graphite pin capable of piercing the first septum of the first cap. The first graphite pin preferably has a diameter in the range of 1 to 3 mm and particularly preferably electrically contacts the working electrode. The first graphite pin may also contact a third wall arranged in the interior of the device and in contact with an upper side of a flat working electrode of the device. This enables more stable contact with the flat working electrode.

[0058] The device may further include a second graphite pin suitable for piercing the second septum of the second cap. The second graphite pin preferably has a diameter in the range of 1 to 3 mm and particularly preferably electrically contacts the counterelectrode. The second graphite pin may also contact a fourth wall arranged in the interior of the device and in contact with an upper side of a flat counterelectrode of the device. This enables more stable contact with the flat counterelectrode.

[0059] Apart from that, the device may (already) contain an electrolyte located in the interior of the hollow base body.

[0060] Furthermore, the device may include at least one cannula that pierces a third septum of the hollow body. This may allow pressure equalization if an electrochemical reaction involving the release of a gas is being investigated.

[0061] In a particularly preferred embodiment, the device contains no metal or metal alloy. This embodiment has the advantage of reducing the amount of interference signals that can occur during a measurement, thus enabling a more precise and reproducible measurement.

[0062] According to the invention, a use of the device according to the invention for carrying out an electrochemical reaction in a nuclear magnetic resonance apparatus is further proposed, wherein the use preferably involves a use of the device according to the invention for in-situ imaging of an electrochemical reaction via a nuclear magnetic resonance apparatus.

[0063] The subject matter of the invention will be explained in more detail with reference to the following figures and the following example, without wishing to restrict it to the specific embodiments shown here.

[0064] Fig. Figure 1 schematically shows a device according to the invention without the two caps. The device contains a hollow base body 1 having an interior space 2, wherein the hollow base body 1 has the shape of a right circular cylinder at a first end along a longitudinal axis L of the hollow base body 1 and the shape of a right circular cylinder at a second end, which is opposite the first end. The first cap and the second cap of the device according to the invention are not shown here. Visible here is the first flat wall 7, which has a top side and a bottom side and is suitable for arranging a working electrode on its top side and a counter electrode on its bottom side. The hollow base body has a first (larger) bulge 12 and a second (smaller) bulge 13, which give part of the interior space of the hollow base body 1 the shape of an angular cone.

[0065] Fig. Figure 2 shows schematically two cross sections through the device according to the invention, a cross section from above ( Fig. 2A) and a cross-section from the side ( Fig.2B). The device comprises a hollow base body 1, the interior 2 of which is closed by the first cap 3 and the second cap 5 (screw cap), whereby the two caps 3, 5 each have a septum 4, 6. The working electrode 8 is arranged on the upper side of the first flat wall 7 and the second flat wall 10 of the device, and the counter electrode 9 is arranged on the underside of the first flat wall 7 and the second flat wall 10. The hollow base body 1 has a first (larger) bulge 12 and a second (smaller) bulge 13, which give a part 11 of the interior 2 of the hollow base body 1 the shape of a square cone. The first (larger) bulge 12 here has an opening 14, through which an additional electrode 20 (e.g.a reference electrode, an electrode for measuring a pH value and / or an electrode for measuring a temperature) can be inserted into the interior 2 of the tall base body 1. The additional electrode 20 can be arranged in a groove 15 located in the region of the second (smaller) bulge 13, thereby improving the stability of the arrangement of the additional electrode 20 within the interior 2. The hollow base body 1 also has a first wall 16, which offers a lateral stop surface for the working electrode 8, and a second wall 17, which offers a lateral stop surface for the counter electrode 10. Furthermore, the hollow base body has a third wall 18, which offers a stop surface for the top side of the working electrode 8, and a fourth wall 19, which offers a stop surface for the top side of the counter electrode 10.The walls 16, 17, 18, 19 can ensure that the working electrode 8 and the counter electrode 10 are stably arranged within the interior of the device. The illustration also shows a first graphite pin 21, which pierces the first septum 4 of the first cap 3 and makes electrical contact with the working electrode 8, and a second graphite pin 22, which pierces the second septum 6 of the second cap 5 and makes electrical contact with the counter electrode 10. Example - Production of a device according to the invention

[0066] First, the hollow base body of the device according to the invention is manufactured using 3D printing (e.g., from polypropylene). Subsequently, the working electrode is placed on the first flat wall of the device, and the counter electrode is placed on the second flat wall of the device. The two ends of the hollow base body are then each sealed with a commercially available ND13 screw cap containing a septum.

[0067] The interior of the device can now be filled with the desired electrolyte through the two septa using a cannula. The maximum volume can be 1 ml, for example.

[0068] To electrically connect the working electrode and the counter electrode, they are each connected with a graphite pin, which is pierced through the two septa. Walls in the interior of the hollow base body of the device can simplify the alignment and contacting of the respective graphite pins.

[0069] The two graphite pins can then be connected to an electrical voltage source and the device can be inserted into a magnetic resonance scanner to monitor an electrochemical reaction using NMR in situ and in operando.

[0070] If the device is to be used as a flow cell, an electrolyte can be fed into the interior of the device via the two septa of the two caps of the device (e.g. through a cannula that pierces the septa) and can also be fed out of the interior of the device (e.g. also circulated). This can be used to generate a gas flow through the device in addition to or alternatively to a liquid flow. A curvature of the hollow base body can help to channel gas that is formed during an electrochemical reaction. To prevent a pressure increase in the cell, it may be possible to discharge the resulting gas via an opening in the hollow base body (e.g. via a cannula that pierces a septum in an opening of the hollow base body).

[0071] If a reference electrode is used, it can be inserted into the interior of the device through an opening in the hollow body. A septum in the opening and a groove in the hollow body can help to securely position the reference electrode within the device. List of reference symbols 1 hollow base body; 2 Interior of the hollow base body; 3 first cap; 4 first septum; 5 second cap; 6 second septum; 7 first flat wall; 8 working electrode; 9 Counter electrode; 10 second flat wall; 11 Part of the interior of the hollow base body (angular cone); 12 first bulge of the hollow base body; 13 second bulge of the hollow base body; 14 Opening of the hollow body (optionally with third septum); 15 Groove of the hollow base body; 16 first wall of the hollow base body; 17 second wall of the hollow base body; 18 third wall of the hollow base body; 19 fourth wall of the hollow base body; 20 additional electrodes (e.g. reference electrode); 21 first graphite pencil; 22 second graphite pencil; L Longitudinal axis of the hollow base body. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited non-patent literature

[0000] Richter, JB et al., Chem. Comm., 2019, 55:6042-6045

[0003] Durajski, AP et al., Acta Physica Polonica A, 2020, 138(2):148-151

[0004]

Claims

[1] Device suitable for carrying out an electrochemical reaction in a nuclear magnetic resonance apparatus, containing or consisting of: a) a hollow base body having an interior space, the hollow base body having a shape of a right circular cylinder at a first end along a longitudinal axis of the hollow base body and a shape of a right circular cylinder at a second end opposite the first end; b) a first cap which is connectable or connected to the first end of the hollow base body via a reversible, fluid-tight connection, wherein the first cap has, at least in regions along a surface extending perpendicular to the longitudinal axis of the hollow base body, a first septum which contacts a wall of the first cap; c) a second cap which is connectable or connected to the second end of the hollow base body via a reversible, fluid-tight connection, and wherein the second cap has, at least in regions along a surface extending perpendicular to the longitudinal axis of the hollow base body, a second septum which contacts a wall of the second cap; d) a first planar wall having a top side and a bottom side and being suitable for arranging a working electrode on the top side thereof and a counter electrode on the bottom side thereof, wherein the first planar wall is arranged in the interior of the hollow base body and is connected to an inner wall of the hollow base body via an irreversible connection, wherein the first planar wall is arranged parallel to the longitudinal axis of the hollow base body and extends from the first end of the hollow base body towards a center of the hollow base body; and e) a second flat wall having a top side and a bottom side and being suitable for arranging a working electrode on the top side thereof and a counter electrode on the bottom side thereof, wherein the second flat wall is arranged in the interior of the hollow base body and is connected to an inner wall of the hollow base body via an irreversible connection, wherein the second flat wall is arranged parallel to the longitudinal axis of the hollow base body and extends from the second end of the base body towards a center of the hollow base body. [2] Device according to the preceding claim, characterized by that the device contains a flat working electrode with a top side and a bottom side, wherein the bottom side of the flat working electrode is arranged on the top side of the first flat wall and on the top side of the second flat wall, wherein the flat working electrode is preferably i) contains or consists of carbon, wherein the flat working electrode preferably contains or consists of a carbon paper and / or a carbon fabric; and / or ii) along a longitudinal axis of the hollow base body, an extension in the range of 50 to 95%, preferably 60 to 90%, particularly preferably 70 to 85%, of the extension of the hollow base body along its longitudinal axis, in particular an extension in the range of 15 to 25 mm; and / or iii) perpendicular to a longitudinal axis of the hollow base body and parallel to a surface of the flat working electrode, has an extension in the range 18 to 33%, preferably 21 to 31%, particularly preferably 24 to 30%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension of 5 to 10 mm; and / or iv) perpendicular to a longitudinal axis of the hollow base body and perpendicular to a surface of the flat working electrode, has an extension in the range 1 to 10%, preferably 2 to 8%, particularly preferably 4 to 6%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension in the range 0.10 to 0.75 mm. [3] Device according to one of the preceding claims, characterized by that the device contains a flat counter electrode with a top side and a bottom side, wherein the bottom side of the flat counter electrode is arranged on the bottom side of the first flat wall and on the bottom side of the second flat wall, wherein the counter electrode is preferably i) contains or consists of carbon, wherein the counter electrode preferably contains or consists of a carbon paper and / or a carbon fabric; and / or ii) along a longitudinal axis of the hollow base body, an extension in the range of 50 to 95%, preferably 60 to 90%, particularly preferably 70 to 75 to 85%, of the extension of the hollow base body along its longitudinal axis, in particular an extension in the range of 15 to 25 mm; and / or iii) perpendicular to a longitudinal axis of the hollow base body and parallel to a surface of the flat counter electrode, has an extension in the range 18 to 33%, preferably 21 to 31%, particularly preferably 24 to 30%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension of 5 to 10 mm; and / or iv) perpendicular to a longitudinal axis of the hollow base body and perpendicular to a surface of the flat counter electrode, has an extension in the range 1 to 10%, preferably 2 to 8%, particularly preferably 4 to 6%, of the extension of the hollow base body perpendicular to its longitudinal axis, in particular an extension of 0.10 to 0.75 mm. [4] Device according to one of the preceding claims, characterized by that the hollow base body i) contains or consists of a material selected from the group consisting of plastic, glass, ceramic and combinations thereof, wherein the plastic is in particular selected from the group consisting of polyolefins and UV-curable plastics, wherein the plastic is optionally polypropylene; and / or ii) does not have electrical conductivity; and / or iii) is manufactured using 3D printing; and / or iv) has an extension along its longitudinal axis in the range of 10 to 50 mm, preferably 20 to 40 mm, particularly preferably 25 to 30 mm; and / or v) at its first end and / or at its second end, perpendicular to its longitudinal axis, has an extension in the range of 8 to 14 mm, preferably 9 to 13 mm, particularly preferably 10 to 12 mm. [5] Device according to one of the preceding claims, characterized by that the hollow base body between its first end and its second end i) has a part of its interior which, at least in part, has the shape of a square cone; and / or ii) perpendicular to its longitudinal axis, has an extension in the range of >14 to 17 mm, preferably 14.5 to 16 mm, particularly preferably 15 to 15.5 mm; and / or iii) has a first bulge extending the interior in a direction perpendicular to the longitudinal axis of the hollow base body, wherein the first bulge preferably has the shape of a hemisphere at least in some regions and / or has, along a longitudinal axis of the hollow base body, an extension in the range of >25 to 45%, preferably 30 to 42%, particularly preferably 35 to 40%, of the extension of the hollow base body along its longitudinal axis; and / or iv) a second bulge which expands the interior in a direction perpendicular to the longitudinal axis of the hollow base body, wherein the second bulge preferably has the shape of a hemisphere at least in some regions and / or has an extent in the range 5 to 25%, preferably 10 to 22%, particularly preferably 15 to 20%, of the extent of the hollow base body along its longitudinal axis. [6] Device according to one of the preceding claims, characterized by that the hollow base body has an opening between its first end and its second end, preferably at a first bulge of the hollow base body in this region, wherein a third septum is optionally arranged in the opening, which third septum contacts a wall of the hollow base body, wherein the third septum particularly preferably contains or consists of a membrane, wherein the membrane in particular i) contains or consists of an elastomeric plastic, the elastomeric plastic preferably being natural rubber; and / or ii) has a thickness, in a direction along the longitudinal axis of the hollow base body, in the range of 0.5 to 3 mm, preferably 0.75 to 2 mm, particularly preferably 1 to 1.5 mm. [7] Device according to one of the preceding claims, characterized bythat the hollow base body has, between its first end and its second end, preferably at a second bulge of the hollow base body in this region, a groove facing the interior of the hollow base body, which groove is suitable for receiving one end of an additional electrode. [8] Device according to one of the preceding claims, characterized by that the reversible, fluid-tight connection of the first cap to the first end of the hollow base body and / or the reversible, fluid-tight connection of the second cap to the second end of the hollow base body is selected from the group consisting of force-locking connection, form-locking connection and combinations thereof, wherein the reversible, fluid-tight connection is preferably a screw connection. [9] Device according to one of the preceding claims, characterized by that the first cap without its first septum and / or the second cap without its second septum i) contains or consists of a plastic, wherein the plastic is preferably selected from the group consisting of polyolefins, wherein the plastic is particularly preferably polypropylene; and / or ii) is manufactured using 3D printing; and / or iii) is an ND13 screw cap without a septum. [10] Device according to one of the preceding claims, characterized by that the first septum of the first cap and / or the second septum of the second cap contains or consists of a membrane, wherein the membrane is particularly preferably i) contains or consists of an elastomeric plastic, wherein the elastomeric plastic is preferably natural rubber; and / or ii) has a thickness, in a direction along the longitudinal axis of the hollow base body, in the range of 0.5 to 3 mm, preferably 0.75 to 2 mm, particularly preferably 1 to 1.5 mm; and / or iii) a septum of an ND13 screw cap with septum. [11] Device according to one of the preceding claims, characterized by that the first flat wall in the interior of the hollow base body and / or the second flat wall in the interior of the hollow base body i) contains or consists of a material selected from the group consisting of plastic, glass, ceramic and combinations thereof, wherein the plastic is in particular selected from the group consisting of polyolefins and UV-curable plastics, wherein the plastic is optionally polypropylene; and / or ii) is integral with the base body; and / or iii) is manufactured by 3D printing, preferably together with the hollow base body; and / or iv) along a longitudinal axis of the hollow base body, an extension in the range 25 to 45%, preferably 30 to 42%, particularly preferably 35 to 40%, of the extension of the hollow base body along its longitudinal axis; and / or v) perpendicular to a longitudinal axis of the hollow base body and parallel to a surface of the flat wall, has an extension in the range 1 to 10%, preferably 2 to 8%, particularly preferably 4 to 6%, of the extension of the hollow base body perpendicular to its longitudinal axis. [12] Device according to one of the preceding claims, characterized by that the hollow body in its interior i) a first wall for establishing contact with a side surface of a planar working electrode, wherein the first wall extends at the second end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and is connected to an upper side of the second planar wall, wherein the first wall is particularly preferably integral with the second planar wall; and / or ii) a second wall for establishing contact with a side surface of a planar counter electrode, wherein the second wall extends at the first end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and is connected to an underside of the first planar wall, wherein the second wall is particularly preferably integral with the first planar wall; and / or iii) a third wall for establishing contact with an upper side of a planar working electrode, wherein the third wall extends at the first end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and has a distance from the first planar wall that substantially corresponds to a thickness of the planar working electrode in a direction perpendicular to the longitudinal axis of the hollow base body; and / or iv) a fourth wall for establishing contact with an upper side of a planar counter electrode, wherein the fourth wall extends at the second end of the hollow base body substantially perpendicular to the longitudinal axis of the hollow base body and has a distance from the second planar wall which substantially corresponds to a thickness of the planar counter electrode in a direction perpendicular to the longitudinal axis of the hollow base body. [13] Device according to one of the preceding claims, characterized by that the device has an additional electrode, wherein the additional electrode is preferably i) is selected from the group consisting of reference electrode, electrode for measuring a pH value, electrode for measuring a temperature and combinations thereof; and / or ii) is rod-shaped at least in part; and / or iii) contains or consists of a material selected from the group consisting of plastic, glass, ceramic and combinations thereof, wherein the plastic is preferably selected from the group consisting of polyolefins and fluorine-containing plastics, wherein the fluorine-containing plastic is in particular polytetrafluoroethylene; and / or iv) is arranged in a part of the interior of the hollow base body that is located between the first end and the second end of the hollow base body, preferably in a part of its interior that has the shape of an angular cone at least in some regions, wherein the additional electrode is particularly preferably arranged substantially perpendicular to the longitudinal axis of the hollow base body, in particular is arranged in an opening of the hollow base body, wherein the additional electrode is preferably also arranged in a groove of the hollow base body, and wherein the additional electrode optionally pierces a third septum that is arranged in the opening of the hollow base body; and / or v) has a length in the range of 15 to 40 mm. [14] Device according to one of the preceding claims, characterized by that the device i) has a first cannula which pierces the first septum of the cap and is preferably fluidly connected to an electrolyte source; and / or ii) a second cannula which pierces the second septum of the cap and is preferably fluidically connected to an electrolyte sink, wherein the electrolyte sink is optionally an electrolyte source which is fluidically connected to a first cannula of the device which pierces the first septum of the cap; and / or iii) contains a first graphite pin which is suitable for piercing the first septum of the first cap, wherein the first graphite pin preferably has a diameter in the range of 1 to 3 mm and particularly preferably electrically conductively contacts the planar working electrode, optionally also contacts a third wall which is arranged in the interior of the device and has a contact with an upper side of a planar working electrode of the device; and / or iv) contains a second graphite pin which is suitable for piercing the second septum of the second cap, wherein the second graphite pin preferably has a diameter in the range of 1 to 3 mm and particularly preferably electrically conductively contacts the planar counterelectrode, optionally also contacts a fourth wall which is arranged in the interior of the device and has a contact with an upper side of a planar counterelectrode of the device; and / or v) contains an electrolyte located in the interior of the hollow body; and / or vi) contains at least one cannula which pierces a third septum of the hollow body; and / or vii) does not contain any metal or metal alloy. [15] Use of the device according to one of the preceding claims for carrying out an electrochemical reaction in a nuclear magnetic resonance apparatus, preferably for in-situ imaging of an electrochemical reaction via a nuclear magnetic resonance apparatus.

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