FLOW CELL CAVITY ASSISTED CATALYST SYSTEM

Description

TECHNICAL FIELD

The present disclosure relates generally to catalyst systems, and particularly to catalyst systems with a flow cell.

BACKGROUND

The development of active, stable, and low-cost catalysts and catalyst systems is an essential prerequisite for achieving desired electrocatalytic production of chemical products such as hydrogen and oxygen from water and/or the reduction of carbon dioxide into carbon monoxide and oxygen.

The present disclosure addresses issues related to catalyst systems, and other issues related to catalysts.

SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

In one form of the present disclosure, a catalyst system includes a flow-cell cavity, a pair of spaced apart mirrors disposed in the flow-cell cavity, a nanostructured textile catalyst disposed in the flow-cell cavity between the pair of spaced apart mirrors, and an energy source configured to transmit electromagnetic radiation (EMR) waves into the flow-cell cavity between the pair of spaced apart mirrors. Also, the pair of spaced-apart mirrors are configured to trap the EMR waves such that polaritons are formed within the flow-cell cavity and a catalytic reaction of a molecule in the flow-cell cavity is altered compared to when the polaritons are not formed within the flow-cell cavity.

In another form of the present disclosure, a catalyst system includes a flow-cell cavity, a pair of spaced apart gas diffusion layers disposed in the flow-cell activity, a pair of spaced apart mirrors disposed on the pair of spaced apart gas diffusion layers, a nanostructured textile catalyst disposed in the flow-cell cavity between the pair of spaced apart mirrors, and an energy source configured to transmit EMR waves into the flow-cell cavity between the pair of spaced apart mirrors. Also, the pair of spaced-apart mirrors are configured to trap the EMR waves such that polaritons are formed within the flow-cell cavity and a catalytic reaction of a molecule in the flow-cell cavity is altered compared to when the polaritons are not formed within the flow-cell cavity.

In still another form of the present disclosure, a catalyst system includes a flow-cell cavity, a pair of spaced apart gas diffusion layers disposed in the flow-cell activity, and a pair of spaced apart mirrors disposed on the part of spaced apart gas diffusion layers. The pair of spaced apart mirrors are separated by a distance that is a function of a vibration magnitude of a molecule in the flow-cell cavity and the pair of spaced apart mirrors are selected from a pair of gold-coated windows or a pair dielectric layers. The catalyst system also includes a nanostructured textile catalyst disposed in the flow-cell cavity between the pair of spaced apart mirrors and an energy source configured to transmit electromagnetic radiation (EMR) waves into the flow-cell cavity between the pair of spaced apart mirrors. The pair of spaced-apart mirrors are configured to trap the EMR waves such that polaritons are formed within the flow-cell cavity and a catalytic reaction of a molecule in the flow-cell cavity is altered compared to when the polaritons are not formed within the flow-cell cavity.

Further areas of applicability and various methods of enhancing the above technology will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present teachings will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1A illustrates an exploded perspective view of a catalyst system according to the teachings of the present disclosure;

FIG. 1B illustrates an exploded side view of the catalyst system in FIG. 1A;

FIG. 2A illustrates an enlarged view of a portion of an optical cavity in the catalyst system in FIG. 1B; and

FIG. 2B illustrates strong coupling between vibrational modes of molecules in the optical cavity and a cavity mode of the optical cavity in FIG. 2B;

FIG. 3 illustrates a graphical plot of energy as a function of reaction coordinate for a reactant-to-product chemical reaction pathway without the presence of a catalyst, with the presence of a catalyst, and with the presence of a catalyst and polaritons provided by a catalyst system according to the teachings of the present disclosure; and

FIG. 4 is a flow chart for a method of operating a catalyst system according to the teachings of the present disclosure.

It should be noted that the figures set forth herein are intended to exemplify the general characteristics of catalysts system for the purpose of the description of certain aspects. The figures may not precisely reflect the characteristics of any given aspect and are not necessarily intended to define or limit specific forms or variations within the scope of this technology.

DETAILED DESCRIPTION

The present teachings provide a catalyst system that includes a catalyst material for a desired catalytic reaction of molecules, and polaritons that modify the catalytic reaction of the molecules. In some variations, the catalyst system includes a flow cell with a fluid cavity, a nanostructured textile catalyst in the fluid cavity, and an energy source configured to provide energy to molecules in the fluid cavity such that the polaritons are formed within the flow cavity. In at least one variation, the energy source is a thermal energy source. In the alternative, or in addition to, the energy source is an electromagnetic wave radiation (EMR) source such as a microwave source, an infrared (IR) light source, and a laser, among others.

In some variations, a pair of spaced apart panels or layers are disposed in the fluid cavity of the flow cell and the catalyst material is disposed between the pair of spaced apart layers. In at least one variation, the pair of spaced apart layers is a pair of spaced apart mirrors or dielectric layers such that an optical cavity is formed between the pair of spaced apart mirrors. As used herein, the phrase “optical cavity” refers to an arrangement of mirrors or other optical elements that forms a cavity resonator for light waves. And in such variations, the polaritons are formed within the optical cavity.

Referring to FIGS. 1A-1B, an exploded perspective view of a catalyst system 10 according to the teachings of the present disclosure is shown in FIG. 1A and an exploded side view of the catalyst system 10 is shown in FIG. 1B. The catalysts system includes a housing 100. In some variations, the housing includes a first plate 110 and a second plate 120 configured to be attached to each other, e.g., with threaded fasteners (not shown) that extend at least partially through the first plate 110 and the second plate 120. In some variations, the first plate 110 includes a first opening 114 (e.g., a window) and/or the second plate 120 includes a second opening 124 (e.g., a window) such that EMR radiation can propagate through the first plate 110 and/or the second plate 120 as discussed in greater detail below.

A fluid cavity 150 (FIG. 1B) is defined within the housing 100. In variations where the housing 100 includes the first plate 110 and the second plate 120, the fluid cavity is defined between the first plate 110 and the second plate 120. For example, in some variations the first plate 110 and/or the second plate 120 include a first ring portion 119 (FIG. 1B) and/or a second ring portion 129, respectively. Also, a first cavity space (not shown) is defined by and within the first ring portion 119 and an inner (+x direction) surface of the first plate 110, and/or a second cavity space 128 is defined by and within the second ring portion 129 and an inner (−x direction) surface of the second plate 120.

In some variations, the first ring portion 119 and/or the second ring portion 129 are integral with the first plate 110 and/or the second plate 120, respectively, i.e., the first ring portion 119 and/or the second ring portion 129 are part of the first plate 110 and/or the second plate 120, respectively. While in other variations, the first ring portion 119 and/or the second ring portion 129 are not integral with the first plate 110 and/or the second plate 120, respectively. For example, the first ring portion 119 and/or the second ring portion 129 can be a gasket next to or partially embedded in the first plate 110 and/or the second plate 120, respectively.

The housing 100 includes at least inlet 112 in fluid communication with the fluid cavity 150 and at least one outlet 122 in fluid communication with the fluid cavity 150. In variations where the housing 100 includes the first plate 110 and the second plate 120, the first plate 110 can include at least one inlet 112 in fluid communication with the fluid cavity 150 and the second plate 120 can include at least one outlet 122 in fluid communication with the fluid cavity 150. In the alternative, or in addition to, the first plate 110 can include at least one outlet and the second plate 120 can include at least one inlet.

In some variations, the housing 100 includes a first electrically conducting element 116 (e.g., a rod or wire) and/or a second electrically conducting element 126 (FIG. 1B) in electrical communication with the fluid cavity 150. For example, in variations where the housing 100 includes the first plate 110 and the second plate 120, the first plate can include the first electrically conducting element 116 and the second plate 120 can include the second electrically conducting element 126.

Disposed within the fluid cavity 150 is a catalyst layer 130. In some variations, the catalyst layer 130 is a nanostructured textile catalyst layer with nanofibers 132 (FIG. 2A) and catalyst nanoparticles 134 (FIG. 2A). In at least one variation, the nanofibers 132 are water soluble nanofibers such after exposure to water only a skeleton of the catalyst nanoparticles 134 are present during operation of the catalyst system 10. In some variations, the entire catalyst layer 130 is a nanostructure textile catalyst with the nanofibers 132 and catalyst nanoparticles 134, while in other variations only a portion 136 of the catalyst layer 130 includes the nanostructure textile catalyst with the nanofibers 132 and catalyst nanoparticles 134 as illustrated in FIG. 1A.

The nanofibers 132 and/or the catalyst nanoparticles 134 are selected based on or as a function of molecules (products) to be catalyzed within the fluid cavity 150. For example, in some variations water (H₂O) flows into the fluid cavity via the at least inlet 112 and the water is catalyzed by the catalyst nanoparticles 134 into hydrogen (H₂) and oxygen (O₂). And in such variations, the catalyst nanoparticles 134 can include water electrolysis catalytic material such as noble-metal nanoparticles, e.g., nanoparticles containing platinum, iridium, ruthenium, osmium, and alloys thereof, noble-metal oxide nanoparticles, transition metal nanoparticles including nickel-containing nanoparticles iron-containing nanoparticles, transition metal oxide nanoparticles, transition metal alloy nanoparticles, and transition metal alloy oxide nanoparticles, among others. In another example, carbon dioxide (CO₂) flows into the fluid cavity via the at least inlet 112 and the carbon dioxide is catalyzed by the catalyst nanoparticles 134 into carbon monoxide (CO) and oxygen (O₂). And in such variations, the catalyst nanoparticles 134 can include graphene nanoparticles and/or nanoparticles containing copper, copper alloys, iron, iron alloys, gold, gold alloys, silver, silver alloys, and tungsten carbide, among others.

Still referring to FIGS. 1A-1B, in some variations one or more panels or layers 140 are disposed within the fluid cavity 150. In at least one variation, the one or more layers 140 are electrically conducting layers that can be or are in electrical communication with the first electrically conducting element 116 and/or the second electrically conducting element 126 such that electrocatalytic reactions of the molecules in the fluid cavity 150 occurs or is provided. In the alternative, or in addition to, the one or more layers 140 are two layers 140 spaced apart from each other by a predetermined width (x-direction) such that a desired vibration resonance cavity (not labeled) and/or optical cavity (not labeled) is formed for a predefined molecule (product) between the two layers 140 in the fluid cavity 150. And in some variations, the one or more layers 140 include an opening 142 configured for EMR 192 from an EMR source 190 to pass therethrough.

Referring now to FIG. 2A, illustration of one example of a catalytic reaction within the fluid cavity 150 of the catalyst system 10 is shown. As noted above, the fluid cavity 150 includes the catalyst layer 130 with nanofibers 132 and catalyst nanoparticles 134. And for the example shown in FIG. 2A, water molecules (H₂O) are in the fluid cavity 150 and a voltage is applied across the layers 140 such the water molecules undergo electrocatalysis hydrogen gas (H₂) and oxygen gas (only O⁻ shown in the figure) are formed. However, and unlike traditional water electrocatalyst systems, EMR 192 (FIG. 1B) is propagated into fluid cavity 150 such that polaritons ‘p’ are formed within the fluid cavity 150 and the electrocatalysis of the water is enhanced. It should be understood that the in variations where the nanofibers 132 are water soluble nanofibers, the nanofibers 132 are present during operation of the catalyst system 10 and only a skeleton of the catalyst nanoparticles 134 is present in the fluid cavity 150.

Not being bound by theory, and with reference to FIG. 2B, polaritons are quasiparticles that form or result from strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation of a molecule. For example, optical modes, e.g., Fabry-Perot cavity modes, can couple optically active transitions of a nearby material (molecule) when the modes are resonant with one another and have similar decay rates such that hybrid-matter modes call polaritons are formed. FIG. 2B illustrates vibrational modes of a molecule strongly coupled to an optical (cavity) mode, the result being polaritons with two polariton modes, i.e., an upper polariton mode and a lower polariton mode separated by dark modes. In addition, the hybridized states of the upper polariton mode and the lower polariton mode have partial character of the molecule vibration modes and the optical (cavity) mode and thereby provide for the modification of the reaction rate of product molecules to reactant molecules.

Not being bound by theory, the phrase “strong coupling” can be explained as follows. When molecules are within an optical cavity (e.g., two parallel mirrors) with well-defined modes, it is possible to modulate the emission probability (i.e., the probability of photons being emitting from the molecules) by tuning the cavity resonance and thereby controlling the density of optical modes at the emission wavelength. And if the optical cavity is of sufficient quality, the emitted photons can be reabsorbed by the molecules as the molecules bounce back and forth between the two parallel mirrors. In some variations, the exchange of photons is faster than dissipating channels and it is possible to generate hybrid light—matter states, half electronic and half photonic. And the hybrid light—matter states are known as the “strong coupling” regime (e.g., see “Chemistry under Vibrational Strong Coupling”, Nagarajan et al., J. Am. Chem. Soc. 2021, 143, 16877-16889, which is incorporated herein by reference).

For example, and with reference to FIG. 3, a graphical plot of energy as a function of reaction coordinate is shown. As used herein, the phrase “reaction coordinate” refers to an abstract one-dimensional coordinate that represents progress along a chemical reaction pathway. The graphical plot in FIG. 3 shows three energy-reaction coordinate plots (lines). The first line ‘1’ represents the change in energy along the chemical reaction pathway for reactants (e.g., H₂O) to products (e.g., H₂ and O₂) without the presence or use of a catalyst, the second line ‘2’ represents the change in energy along the chemical reaction pathway for the same reactants-to-products with the presence or use of a catalyst, and third line ‘3’ represents the change in energy along the chemical reaction pathway for reactants-to-products with the presence or use of a catalyst and polaritons.

FIG. 3 also illustrates that the activation energy ‘AE1’ for the reactants-to-products chemical pathway without the presence or use of a catalyst (line 1) is greater than the activation energy ‘AE2’ for the reactants-to-products chemical pathway with the presence or use of a catalyst (line 2), which is greater than the activation energy ‘AE3’ for the reactants-to-products chemical pathway with the presence or use of a catalyst and polaritons (line 3).

Referring now to FIGS. 1-4, during operation of the catalyst system 10 a chemical product (e.g., H₂O or CO₂) is introduced into the fluid cavity 150 150 and into contact with the catalyst nanoparticles 134 via the one or more inlets 112 at 200. In some variations, a voltage is applied across the spaced apart layers 140 at 210 and a EMR 192 is transmitted and propagates through the second window 124 and into the fluid cavity 150 such that polaritons p are created via strong coupling of optical modes of the EMR with optically active transitions of the chemical product molecules. As noted above, the polaritons have partial character of the molecule vibration modes and the optical (cavity) mode and thereby modify the reaction rate of product molecules to reactant molecules. For example, in some variations the polaritons increase the rate of catalytic reaction of the product molecules to the reactant molecules. The reactant molecules are removed from the fluid cavity 150 at 230 via the one or more outlets 122.

In some variations, the strong coupling occurs or is mediated by electromagnetic fluctuation of the cavity modes and without the presence of the EMR 192 being transmitted and propagated into the fluid cavity 150 as described in Chemistry under Vibrational Strong Coupling”, Nagarajan et al., J. Am. Chem. Soc. 2021, 143, 16877-16889. Accordingly, in such variations the catalyst system 10 shown in FIG. 1B may not include the EMR source 190.

The preceding description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A or B or C), using a non-exclusive logical “or.” It should be understood that the various steps within a method may be executed in different order without altering the principles of the present disclosure. Disclosure of ranges includes disclosure of all ranges and subdivided ranges within the entire range.

The headings (such as “Background” and “Summary”) and sub-headings used herein are intended only for general organization of topics within the present disclosure, and are not intended to limit the disclosure of the technology or any aspect thereof. The recitation of multiple forms or variations having stated features is not intended to exclude other forms or variations having additional features, or other forms or variations incorporating different combinations of the stated features.

As used herein the term “about” when related to numerical values herein refers to known commercial and/or experimental measurement variations or tolerances for the referenced quantity. In some variations, such known commercial and/or experimental measurement tolerances are +/−10% of the measured value, while in other variations such known commercial and/or experimental measurement tolerances are +/−5% of the measured value, while in still other variations such known commercial and/or experimental measurement tolerances are +/−2.5% of the measured value. And in at least one variation, such known commercial and/or experimental measurement tolerances are +/−1% of the measured value.

As used herein, the terms “comprise” and “include” and their variants are intended to be non-limiting, such that recitation of items in succession or a list is not to the exclusion of other like items that may also be useful in the devices and methods of this technology. Similarly, the terms “can” and “may” and their variants are intended to be non-limiting, such that recitation that a form or variation can or may comprise certain elements or features does not exclude other forms or variations of the present technology that do not contain those elements or features.

The broad teachings of the present disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the specification and the following claims. Reference herein to one aspect, or various aspects means that a particular feature, structure, or characteristic described in connection with a form or variation is included in at least one form or variation. The appearances of the phrase “in one variation” or “in one form” (or variations thereof) are not necessarily referring to the same form or variation. It should be also understood that the various method steps discussed herein do not have to be carried out in the same order as depicted, and not each method step is required in each form or variation.

The foregoing description of the forms or variations has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular form or variation are generally not limited to that particular form or variation, but, where applicable, are interchangeable and can be used in a selected form or variation, even if not specifically shown or described. The same may also be varied in many ways. Such variations should not be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

While particular forms or variations have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or may be presently unforeseen may arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they may be amended, are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents.