DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendments
2. The Applicant’s amendment filed 23 June 2023 is acknowledged. The applicant has cancelled Claim 14. Currently, Claims 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, and 16 are pending and under examination.
Claim Rejections - 35 USC § 102
3. The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
4. Claims 1, 2, 3, 4, 7, 8, 9, 10, 12, 13, 15, and 16 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Klose-Schubert et al.
Klose-Schubert et al. (US Pub. No. 2014/0322631 A1) is directed toward a composite catalyst capable of being using in catalyst coated membranes (abstract).
Regarding Claim 1, Klose-Schubert et al. discloses a coated membrane containing a membrane (i.e.: manufacture of electrodes, catalyst coated membranes, or MEAs in ¶32) with a front and a rear face. For the purpose of Claim 1, the front face is being assigned to the anode and the back face is being assigned to the cathode. Klose-Schubert et al. indicates the anode catalyst is a precious metal, such as IrO2, with a loading of 0.2 to 2.5 mg Ir/cm2 Ir and a cathode catalyst that is a Pt catalyst (e.g.: Pt/C or Pt-Black) with a loading of 0.1 to 1.0 mg Pt/cm2 (¶32). Klose-Schubert et al. further discloses an Ir-based catalyst for OER and the catalyst comprises a support material (i.e.: inorganic oxide) and an iridium coating which is provided on the support material (abstract). Klose-Schubert further discloses the support material (i.e.: the inorganic oxide) has a BET surface area that ranges from 30 m2/g to 200 m2/g and the total catalyst loading (i.e.: iridium oxide and optionally ruthenium oxide) range from 25 wt.% to 70 wt.%. In example 1 (¶38-39), Klose-Schubert et al. explicitly discloses the formation of IrO2 on TiO2 with the TiO2 having a BET surface area of 50 m2/g and catalyst loading of 46 wt.% IrO2 (i.e.: 40 wt.% Ir). A prima facie case of anticipation exists when an example from the prior art falls within claimed range. See MPEP 2131.03(I) - A SPECIFIC EXAMPLE IN THE PRIOR ART WHICH IS WITHIN A CLAIMED RANGE ANTICIPATES THE RANGE.
Regarding Claim 2, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the iridium content of the coating provided on the membrane front face is maximally 0.3 mg Ir/cm2 as supported by ¶32 where the typical range of Ir loading is 0.2 to 2.5 mg Ir/cm2. A prima facie case of anticipation exists when the prior art teaches a range overlapping or touching the claimed range. See MPEP 2131.03(II) - PRIOR ART WHICH TEACHES A RANGE OVERLAPPING OR TOUCHING THE CLAIMED.
Regarding Claim 3, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the catalyst contains iridium in an amount of maximally 40 wt.% as supported by Ex. 1 where the Ir loading is 40 wt.% (¶38-39). A prima facie case of anticipation exists when an example from the prior art falls within claimed range. See MPEP 2131.03(I) - A SPECIFIC EXAMPLE IN THE PRIOR ART WHICH IS WITHIN A CLAIMED RANGE ANTICIPATES THE RANGE.
Regarding Claim 4, Klose-Schubert et al. discloses the coated membrane, wherein the support material has a BET surface area of maximally 65 m2/g as evidenced by the TiO2 support having a BET surface area of 50 m2/g (¶38-39). A prima facie case of anticipation exists when an example from the prior art falls within claimed range. See MPEP 2131.03(I) - A SPECIFIC EXAMPLE IN THE PRIOR ART WHICH IS WITHIN A CLAIMED RANGE ANTICIPATES THE RANGE.
Regarding Claim 7, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the BET surface area of the support material and the iridium content of the catalyst satisfy the formula of Claim 7 by Ex. 1 (¶38-39). When the BET surface area value (50 m2/g in Ex. 1) is input into the formula in Claim 7, the resultant values are a minimum of 32 and a maximum of 64. Therefore, the Ir-G (i.e.: 40 wt.% Ir) taught in Ex. 1 of Klose-Schubert et al. falls within the limits of the formula of Claim 7 of the instant application A prima facie case of anticipation exists when an example from the prior art falls within claimed range. See MPEP 2131.03(I) - A SPECIFIC EXAMPLE IN THE PRIOR ART WHICH IS WITHIN A CLAIMED RANGE ANTICIPATES THE RANGE.
Regarding Claim 8, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the catalyst has a core-shell structure in which the support material is the core and the iridium-containing coating forms the shell as indicated in ¶30 where it is written, “the iridium oxide particles are precipitated in a very fine, nano-sized form on or at the surface of the inorganic oxide.”
Regarding Claim 9, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the iridium is present in both 3+ and 4+ oxidation states, i.e.: Ir(III) and Ir(IV) (¶24). In particular, Klose-Schubert et al. indicates that the Ir present is predominantly in the 4+ oxidation state as IrO2, but may also present as Ir2O3 (i.e.: Ir3+) depending upon the manufacturing conditions.
Regarding Claim 10, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the support material is an oxide of a transition metal (e.g.: TiO2 or ZrO2), an oxide of a main group element (e.g.: Al2O3), or SiO2 as per ¶21 and ¶27. Example 1 specifically uses TiO2 as the support material in Klose-Schubert et al. (¶38-39).
Regarding Claim 12, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein the coating provided on the membrane front face contains an ionomer (¶9, ¶13, and ¶32). In ¶32, Klose-Schubert explicitly discloses an ionomer is used in the preparation of CCM for use in a PEM and the ionomer can be Nafion (¶7) which is a sulfonic acid-group containing ionomer.
Regarding Claim 13, Klose-Schubert et al. discloses the coated membrane according to Claim 1, wherein a coating containing a catalyst for a hydrogen evolution reaction is applied to the rear face of the membrane as indicated in ¶32 with a Pt-based cathode catalyst (e.g.: Pt/C or Pt-Black). As explained above for the purpose of the instant application, the cathode side of the membrane is the rear side.
Regarding Claim 15, Klose-Schubert et al. discloses a water electrolysis cell contained the coated membrane according to Claim 1 (abstract, ¶22, ¶24, ¶32, and Claim 12 of Klose-Schubert et al.).
Regarding Claim 16, Klose-Schubert et al. discloses the coated membrane according to Claim 12, wherein the ionomer comprises a polymer which contains sulfonic acid-group containing monomers as evidenced by the use of ionomers or Nafion (¶7, ¶9, ¶13, and ¶32). In ¶32, Klose-Schubert explicitly discloses an ionomer is used in the preparation of CCM for use in a PEM and the ionomer can be Nafion (¶7) which is a sulfonic acid-group containing ionomer.
Claim Rejections - 35 USC § 103
6. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
7. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
8. Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Klose-Schubert et al.
Klose-Schubert et al. (US Pub. No. 2014/0322631 A1) is directed toward a composite catalyst capable of being using in catalyst coated membranes (abstract).
Regarding Claim 11, Klose-Schubert et al. discloses the coated membrane according to Claim 1, but does not explicitly state the coating thickness (in microns) of the membrane front face. However, the thickness range of the coating on the front face of the membrane can be derived from Ex. 1 (¶38-39) and the coating weight range of the anode (¶32). Therefore, Klose-Schubert et al. teaches an anode coating thickness range of ~1 micron to 8 microns (see the box below for the calculation). It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Ex. 1 discloses a composite catalyst of 46 wt.% IrO2 and 54 wt. TiO2
TiO2 has a density of 4.23 g/cm3 and IrO2 has a density of 11.66 g/cm3
IrO2 is 85.73 wt.% iridium and 14.27 wt.% oxygen
Ir coating weight range: 0.2 mg Ir/cm2 to 2.5 mg Ir/cm2
Density of the composite is calculated as weighted average
Density of the composite (TiO2+IrO2) = (54%)(4.23 g/cm3) + (46%)(11.66 g/cm3))
Density of the composite (TiO2+IrO2) = (2.28 + 5.36) g/cm3 = 7.64 g/cm3 = 7640 mg/cm3
IrO2 coating weight range is calculated from the Ir/IrO2 weight ratio
IrO2 coating weight range = (0.2 mg cm-2/0.8573) to (2.5 mg cm-2/0.8573)
IrO2 coating weight range = 0.233 mg IrO2/cm2 to 2.92 mg IrO2/cm2
TiO2 coating weight range is calculated from the IrO2 coating weight range
TiO2 coating weight range (min) = 0.233 mg IrO2/cm2 (54 wt.% TiO2/46 wt.% IrO2)
TiO2 coating weight range (min) = 0.274 mg TiO2/cm2
TiO2 coating weight range (max) = 2.92 mg IrO2/cm2 (54 wt.% TiO2/46 wt.% IrO2)
TiO2 coating weight range (max) = 3.43 mg TiO2/cm2
Total Coating Weight Range (TiO2+IrO2) is calculated from the individual coating weights
Total Coating Weight Range (TiO2+IrO2)min = 0.233 + 0.274 = 0.507 mg oxides/cm2
Total Coating Weight Range (TiO2+IrO2)max = 2.92 + 3.43 = 6.35 mg oxides/cm2
Coating Thickness Range is calculated from composite density and total coating weight
Minimum Thickness = (0.507 mg oxides/cm2)(1 cm3/7640 mg)(104 µm/1 cm) = ~1 µm
Maximum Thickness = (6.35 mg oxides/cm2)(1 cm3/7640 mg)(104 µm/1 cm) = ~8 µm
Klose-Schubert discloses an anode coating thickness of ~1 µm to ~8 µm
10. Claims 1, 2, 3, 4, 5, 6, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Klose-Schubert et al. in view of Hartwig-Weiss et al.
Klose-Schubert et al. (US Pub. No. 2014/0322631 A1) is directed toward a composite catalyst capable of being using in catalyst coated membranes (abstract). Hartwig-Weiss et al. (“Iridium Oxide Catalyst Supported on Antimony-Doped Tim Oxide for High Oxygen Evolution Reaction Activity in Acidic Media,” ACS Appl. Nano Mater. 2020, 3, 2185-2196) is directed towards an OER catalyst (pg. 2185: title).
Regarding Claim 1, Klose-Schubert et al. discloses a coated membrane containing a membrane (i.e.: manufacture of electrodes, catalyst coated membranes, or MEAs in ¶32) with a front and a rear face. For the purpose of Claim 1, the front face is being assigned to the anode and the back face is being assigned to the cathode. Klose-Schubert et al. indicates the anode catalyst is a precious metal, such as IrO2, with a loading of 0.2 to 2.5 mg Ir/cm2 Ir and a cathode catalyst that is a Pt catalyst (e.g.: Pt/C or Pt-Black) with a loading of 0.1 to 1.0 mg Pt/cm2 (¶32). Klose-Schubert et al. further discloses an Ir-based catalyst for OER and the catalyst comprises a support material (i.e.: inorganic oxide) and an iridium coating which is provided on the support material (abstract). Klose-Schubert further discloses the support material (i.e.: the inorganic oxide) has a BET surface area that ranges from 30 m2/g to 200 m2/g and the total catalyst loading (i.e.: iridium oxide and optionally ruthenium oxide) range from 25 wt.% to 70 wt.%. In example 1 (¶38-39), Klose-Schubert et al. explicitly discloses the formation of IrO2 on TiO2 with the TiO2 having a BET surface area of 50 m2/g and catalyst loading of 46 wt.% IrO2 (i.e.: 40 wt.% Ir).
One of the key challenges of polymer electrolyte membrane water electrolysis is the high cost Ir and the high loadings (e.g.: 25 to 70 wt.% Ir) required for efficient OER catalysis (Hartwig-Weiss et al. on pg. 2185: introduction). It would be advantageous to reduce the loadings of Ir required for efficient catalysis from both a cost and resource conservation perspective. Hartwig-Weiss et al. discloses the use of highly (electrically) conductive ATO (“Antimony-doped Tin Oxide”) as a support for hydrous iridium oxide as an OER catalyst (pg. 2185: title). The ATO support synthesized in Weiss-Hartwig et al. has a BET surface area of 50 m2/g and high electrical conductivity (pg. 2188: III. Results and Discussion). Iridium nanoparticles were loaded onto the support at levels of 11.0, 15.3, and 23.4 wt.% (pg. 2187: Preparation of ATO-Supported Iridium Catalysts) and subsequently oxidized to form hydrous IrO2 or Ir(OH)4 (pg. 2190). According to the abstract graphic of Hartwig-Weiss et al., the Ir coating weight of the 11 wt.% Ir on ATO is ~0.14 mg Ir/cm2. Even at the low Ir loading, the catalyst of Hartwig-Weiss et al. has excellent electrochemical performance (pg. 2191: Figure 4).
It would be obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the coated membrane of Klose-Schubert et al. with the low Ir content catalyst supported on ATO of Hartwig-Weiss et al. with the reasonable expectation for forming an active OER catalyst with better electrical conductivity at a lower cost.
It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Regarding Claim 2, Klose-Schubert et al. in view of Hartwig-Weiss et al. discloses the coated membrane according to Claim 1, wherein the iridium content of the coating provided on the membrane front face is maximally 0.3 mg Ir/cm2 as supported the example of 11 wt.% Ir in Hartwig-Weiss et al. that has a coating weight of 0.14 mg Ir/cm2 (pg. 2185: TOC graphic). It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Regarding Claim 3, Klose-Schubert et al. in view of Hartwig-Weiss et al. discloses the coated membrane according to Claim 1, wherein the catalyst contains iridium in an amount of maximally 40 wt.% as supported the example of 11 wt.% Ir in Hartwig-Weiss et al. that has a coating weight of 0.14 mg Ir/cm2 (pg. 2185: TOC graphic). It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Regarding Claim 4, Klose-Schubert et al. in view of Hartwig-Weiss et al. discloses the coated membrane, wherein the support material has a BET surface area of maximally 65 m2/g as evidenced by the ATO support in Hartwig-Weiss et al that has a BET surface area of 50 m2/g (pg. 2188: III. Results and Discussion). It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Regarding Claim 5, Klose-Schubert et al. in view of Hartwig-Weiss et al. discloses the coated membrane according to Claim 1, wherein the Ir-containing coating provided on the support material has an average thickness in the range of 1.0 nm to 5.0 nm as supported by Figure 1c (pg. 2187). Figure 1c is an SEM image of the 11 wt.% Ir catalyst deposited onto ATO with an inset particle size distribution. The inset particle size distribution indicates that particles have an average size between 1 and 2 nm which is the effective thickness of the coating (pg. 2186: Scheme 1). It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Regarding Claim 6, Klose-Schubert et al. in view of Hartwig-Weiss et al. discloses the coated membrane according to Claim 1, wherein the catalyst contains 5 to 35 wt.% Ir and the Ir content level on the anode side of the membrane is 0.03 to less than 0.20 mg Ir/cm2 as evidenced by the 11 wt.% Ir on ATO example in Hartwig-Weiss et al. that has a coating weight of 0.14 mg Ir/cm2 (pg. 2185: TOC graphic). It has been held that a prima facie case of obviousness exists when the prior art overlaps with the claimed range. See MPEP 2144.05(I) - OVERLAPPING, APPROACHING, AND SIMILAR RANGES, AMOUNTS, AND PROPORTIONS.
Although, Hartwig-Weiss et al. discloses the use of an ATO support that has a BET surface area of 50 m2/g, the BET surface area is capable of being modulated since the ATO support was synthesized (pg. 2186-7: ATO Synthesis). Hartwig-Weiss et al. indicates that longer heating increases the particle size of nanomaterials which in turn would decrease their overall surface area (pg. 2188). Hartwig-Weiss et al. further teaches that the surface area of the support needs to be optimized to ensure appropriate catalyst dispersion on the surface of the support (pg. 2190: III. Results and Discussion). Therefore, Hartwig-Weiss et al., the BET surface area of the (ATO) support is a result-effective variable, i.e., a variable which achieves a recognized result, and the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation (See MPEP 2144.0.II.B.). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have discovered the optimum or workable ranges of the BET surface area of the ATO support, including values within the claimed range (i.e.: 2-35 m2/g), through routine experimentation. One would have been motivated to do so in order to optimize the Ir-catalyst dispersion on the surface of the ATO support.
Regarding Claim 10, Klose-Schubert et al. in view of Hartwig-Weiss et al. discloses the coated membrane according to Claim 1, wherein the support material is an oxide of a main group metal by the use of ATO, i.e.: antimony and tin (Hartwig-Weiss et al. on pg. 2186-7: ATO Synthesis).
Conclusion
11. The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Haas et al. (US Pub. No. 2019/0379058 A1) is directed towards an electrocatalyst composition (title).
12. Any inquiry concerning this communication or earlier communications from the examiner should be directed to KEVIN SYLVESTER whose telephone number is (703)756-5536. The examiner can normally be reached Mon - Fri 8:15 AM to 4:30 PM EST.
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/KEVIN SYLVESTER/Examiner, Art Unit 1794
/JAMES LIN/Supervisory Patent Examiner, Art Unit 1794