DETAILED ACTION
Notice of Pre-AIA or AIA Status
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
This is a final office action in response to applicant's arguments and remarks filed on 10/07/2025.
Status of Rejections
The objections to the specification and claims are withdrawn in view of applicant’s amendments.
The rejection(s) of claim(s) 3 is/are obviated by applicant’s cancellation.
All other previous rejections are withdrawn in view of applicant’s amendments.
New grounds of rejection are necessitated by applicant’s amendments.
Claims 2 and 4-13 are pending and under consideration for this Office Action.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 11 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 11 recites the limitation "the electrocatalyst has an average cavity size ranging from about 175 to about 185 nm" in lines 3-4. In lines 5-6 of claim 1, upon which it depends, the limitation of “the electrocatalyst has an average cavity size ranging from about 180 to about 185 nm”, which is narrower than the limitation of claim 11. It is therefore unclear which range of cavity sizes applies to the invention of claim 11.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 2, 4-5, 7-8 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Zheng et al. (“Highly efficient CO2 reduction on ordered porous Cu electrode derived from Cu2O inverse opals”, Nano Energy, 2018) in view of Martens et al. (WO 2007/059573).
Regarding claim 2, Zheng teaches a method for electrochemical conversion of CO2 to CO (see e.g. Page 94, Col. 1, lines 14-17) comprising:
providing a working electrode comprising an electrocatalyst, wherein the electrocatalyst comprises a 3D interconnected porous copper inverse-opal structure (see e.g. Scheme 1(c), Cu2O inverse opal (IO) structure electrocatalyst as working electrode; Page 94, Col. 1, 10-16, and Col. 2, under “Electrochemical measurement”, lines 7-8);
applying a negative potential to the working electrode (see e.g. Figs 4a and 5a-d, negative potentials up to -1.0 V applied); and
contacting the working electrode with CO2, wherein the CO2 is reduced to CO (see e.g. Page 94, Col. 1, lines 14-17, and Col. 2, under “Electrochemical measurement”, lines 14-20, CO2 introduced to electrolyte to be reduced to products including CO on the Cu-IO working electrode).
Zheng does not teach the electrocatalyst having an average cavity size ranging from about 180 to about 185 nm, instead teaching the cavity sizes being 340 nm (see e.g. Page 96, Col. 2, lines 12-14).
Martens teaches a catalyst composition having an inverse-opal structure (see e.g. Page 4, line 26-Page 5, line 1) which may comprise copper oxide (see e.g. Page 5, lines 1-5), wherein the cavity size of the inverse opal structure is varied with different initial opal sizes, including an example with inverse opal cavity sizes of 153 to 185 nm (see e.g. Table 2, 169±16 nm), overlapping the claimed range of the present invention. The different cavity sizes result in different surface areas of the overall structure, with lower cavity sizes trending to have a higher surface area (see e.g. Fig. 4). Zheng additionally teaches that increased surface area in the inverse opal structure is beneficial for catalytic activity, as it provides increased reaction active sites (see e.g. Zheng Page 94, Col. 1, lines 10-14).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the electrocatalyst of Zheng to have a decreased cavity size of, for instance, 169±16 nm, overlapping the claimed range, as taught by Martens in order to provide increased surface area and thereby increased activity. MPEP § 2144.05 I states “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists.”
Regarding claim 4, modified Zheng teaches the inverse-opal structure having a hexagonal structure (see e.g. Zheng Page 95, Col. 2, lines 12-14).
Regarding claim 5, modified Zheng teaches the inverse-opal structure being a negative replica of opal (see e.g. Zheng Scheme 1, Page 94, Col. 1, under “Materials”, lines 1-3, the inverse opal structure is a negative replica of polystyrene “opal templates” which are removed).
Though modified Zheng does not teach this negative replica being of poly (methyl methacrylate) opal, this limitation of the opal on which the inverse opal is based being poly (methyl methacrylate) is not a positive recitation of the structure of the inverse opal, instead referring to how it is made. Zheng teaches the inverse-opal structure being a negative replica of polystyrene opals (see e.g. Zheng Scheme 1, Page 94, Col. 1, under “Materials”, lines 1-3, the inverse opal structure is a negative replica of polystyrene “opal templates” which are removed), which would provide the same resulting inverse opal structure as described on Page 9, lines 7-13 of the instant specification.
Regarding claim 7, modified Zheng teaches the method having a Faradaic efficiency between about 67% and 79% at -0.7 V vs. RHE (see e.g. Zheng Fig. 5d, extrapolated from the ~65% FE for CO2 reduction at -0.8 V and 79% FE at -0.6 V; Page 97, Col. 2, lines 6-8).
Regarding claim 8, modified Zheng teaches the Faradaic efficiency being 79% at -0.6 V vs RHE (see e.g. Zheng Fig. 5d; Page 97, Col. 2, lines 6-8).
Regarding claim 13, modified Zheng teaches the electrocatalyst comprising copper in a 0 oxidation state when the negative potential is applied to the working electrode (see e.g. Zheng Page 96, Col. 1, under section “3.2”, lines 1-2 and 14-17, and Col. 2, lines 7-9, all oxides of Cu2O-IO reduced to 0 oxidation Cu-IO to be used as the electrode).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Zheng in view of Martens, as applied to claim 2 above, and further in view of Aizenberg et al. (U.S. 2019/0111657).
Regarding claim 6, modified Zheng teaches all the elements of the method of claim 2 as stated above. Modified Zheng does not teach the 3D interconnected porous copper inverse-opal structure comprising nanoparticles with an average mean diameter ranging from about 15 to about 20 nm.
Martens further teaches the catalyst having an inverse opal structure (see e.g. Page 4, lines 24-25) wherein the pores of the structure are doped with catalytic nanoparticles (see e.g. Page 8, lines 11-13). The inclusion of these nanoparticles increases the surface area of the catalyst which thereby increases its catalytic activity (see e.g. Page 8, lines 13-15). Zheng similarly teaches that increased surface area in the inverse opal structure is beneficial for catalytic activity, as it provides increased reaction active sites (see e.g. Zheng Page 94, Col. 1, lines 10-14).
Aizenberg teaches a catalyst composition (see e.g. Paragraphs 0066 and 0069, photonic structure used as a catalyst) having inverse-opal structure (see e.g. Paragraphs 0095 and 0097) which may be formed of copper oxide nanocrystals with sizes of 1-20 nm (see e.g. Paragraph 0110), overlapping the claimed range of the present invention (see MPEP § 2144.05 as cited above).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the copper oxide of the composition of modified Zheng to comprise copper oxide nanocrystals with sizes of 1-20 nm as taught by Aizenberg as an alternate means to form the copper oxide inverse opal structure which additionally provides increased surface area and thereby increased catalytic activity as taught by Martens.
Claims 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over Zheng in view of Martens, as applied to claim 2 above, and further in view of Hall et al. (“Mesostructure-Induced Selectivity in CO2 Reduction Catalysis”, J. Am. Chem. Soc., 2015).
Regarding claim 9, modified Zheng teaches all the elements of the method of claim 2 as stated above. Modified Zheng does not teach the CO2 being converted to CO with a CO to H2 selectivity greater than about 80% at -0.8 V vs RHE, but does teach the desire for electrodes for CO2 reduction to have increased selectivity for CO2 reduction products such as CO relative to hydrogen evolution (see e.g. Zheng connecting paragraph of Pages 93-94).
Hall teaches a catalyst composition for CO2 reduction having an inverse opal structure (see e.g. Abstract), wherein the selectivity for CO production can be increased by modifying the porous film thickness and mesostructure (see e.g. Page 14834, Col. 2, lines 17-26), with increased film thickness and porosity improving selectivity of CO relative to HER (see e.g. Page 14835, Col. 2, lines 5-10). The CO to H2 selectivity is particularly increased to up to 99% at -0.4 V vs RHE with optimal mesoporosity (see e.g. Abstract), further increasing at more negative values of V vs RHE (see e.g. Fig. 2, as the values of V vs RHE become more negative, CO production increases while H2 production decreases).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the inverse opal electrocatalyst of modified Zheng to have increased selectivity for CO up to 99% by modification of the porous film thickness and mesostructure or porosity as taught by Hall as a means to obtain the increased selectivity already desired by Zheng.
Regarding claim 10, Zheng as modified by Hall teaches the CO to H2 selectivity being greater than 99% at -0.7 V vs. RHE (see e.g. Hall Abstract and Fig. 2b, Hall teaches the tuned CO selectivity being 99% at -0.4 V vs. RHE, and only increasing with higher voltage values through -0.7 V vs. RHE).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Zheng in view of Martens, as applied to claim 2 above, and further in view of Hall.
Regarding claim 11, modified Zheng teaches all the elements of the method of claim 2 as stated above. Zheng as modified by Martens further teaches the inverse-opal structure having a hexagonal structure (see e.g. Zheng Page 95, Col. 2, lines 12-14), the inverse-opal structure being a negative replica of opal (see e.g. Zheng Scheme 1, Page 94, Col. 1, under “Materials”, lines 1-3, the inverse opal structure is a negative replica of polystyrene “opal templates” which are removed), the electrocatalyst having am average cavity size ranging from 153 to 185 nm (see e.g. Martens Table 2, 169±16 nm), overlapping the claimed range of the present invention (see MPEP § 2144.05 as cited above), and the method having a Faradaic efficiency of 79% at -0.6V vs RHE (see e.g. Zheng Fig. 5d; Page 97, Col. 2, lines 6-8).
Though modified Zheng does not teach the negative replica being of poly (methyl methacrylate) opal, this limitation of the opal on which the inverse opal is based being poly (methyl methacrylate) is not a positive recitation of the structure of the inverse opal, instead referring to how it is made. Zheng teaches the inverse-opal structure being a negative replica of polystyrene opals (see e.g. Zheng Scheme 1, Page 94, Col. 1, under “Materials”, lines 1-3, the inverse opal structure is a negative replica of polystyrene “opal templates” which are removed), which would provide the same resulting inverse opal structure as described on Page 9, lines 7-13 of the instant specification.
Modified Zheng does not teach the CO2 being converted to CO with a CO to H2 selectivity greater than about 90% at -0.7 V vs RHE, but does teach the desire for electrodes for CO2 reduction to have increased selectivity for CO2 reduction products such as CO relative to hydrogen evolution (see e.g. Zheng connecting paragraph of Pages 93-94).
Hall teaches a catalyst composition for CO2 reduction having an inverse opal structure (see e.g. Abstract), wherein the selectivity for CO production can be increased by modifying the porous film thickness and mesostructure (see e.g. Page 14834, Col. 2, lines 17-26), with increased film thickness and porosity improving selectivity of CO relative to HER (see e.g. Page 14835, Col. 2, lines 5-10). The CO to H2 selectivity is particularly increased to up to 99% at -0.4 V vs RHE with optimal mesoporosity (see e.g. Abstract), further increasing at more negative values of V vs RHE (see e.g. Fig. 2, as the values of V vs RHE become more negative, CO production increases while H2 production decreases).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the inverse opal electrocatalyst of modified Zheng to have increased selectivity for CO up to 99% by modification of the porous film thickness and mesostructure or porosity as taught by Hall as a means to obtain the increased selectivity already desired by Zheng.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Zheng in view of Martens, as applied to claim 2 above, and further in view of Ke et al. (“Selective formation of C2 products from the electrochemical conversion of CO2 on CuO-derived copper electrodes comprised of nanoporous ribbon arrays”, Catalysis Today, 2016).
Regarding claim 12, modified Zheng teaches all the elements of the method of claim 2 as stated above. Modified Zheng does not teach the electrocatalyst comprising copper in a +2 oxidation state in the providing step, instead teaching it comprising copper in a +1 oxidation state as Cu2O which is reduced to a 0 oxidation state Cu for the CO2 reduction (see e.g. Page 94, Col. 1, lines 14-16, and Page 96, Col. 1, under section “3.2”, lines 1-2 and 14-17, and Col. 2, lines 7-9).
Ke teaches a porous copper electrode for electrochemical conversion of CO2 (see e.g. Abstract) to products including CO and other hydrocarbons (see e.g. connecting paragraph of Pages 20-21, lines 13-20), wherein the copper is derived from reduction of CuO, i.e. +2 oxidation state copper (see e.g. Page 19, Col. 1, bottom paragraph, lines 1-2 and 12-14), resulting in higher activity and selectivity for C2 products than when derived from other copper oxides such as Cu2O (see e.g. Page 21, Col. 2, lines 17-24).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the electrocatalyst of modified Zheng to be first provided in a +2 copper oxidation state as CuO instead of as +1 oxidation Cu2O as taught by Ke to provide higher activity and selectivity for C2 products.
Response to Arguments
Applicant’s arguments, see pages 6-7, filed 10/07/2025, with respect to the rejection(s) of amended claim(s) 2 under 35 USC 102 over Zheng, particularly regarding the cavity size, have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Zheng and Martens.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/M.S.J./Examiner, Art Unit 1795
/LUAN V VAN/Supervisory Patent Examiner, Art Unit 1795