Ex Parte Alibabaei et al

Patent Trial and Appeal Board

Aug 27, 2018

14479995 (P.T.A.B. Aug. 27, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/479,995 09/08/2014
65770 7590 08/29/2018
Thrive IP
5401 NETHERBY LANE
SUITE 1201
NORTH CHARLESTON, SC 29420
FIRST NAMED INVENTOR
Leila Alibabaei
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
1062.0011-USl 6480
EXAMINER
MA YES, MEL VIN C
ART UNIT PAPER NUMBER
1732
NOTIFICATION DATE DELIVERY MODE
08/29/2018 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
JEREMY.STIPKALA@Thrive-IP.COM
docket@thrive-ip.com
rebecca.seaman@thrive-ip.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte LEILA ALIBABAEI, MATTHEW KYLE BRENNAMAN,
MICHAEL NORRIS, GREGORY N. PARSONS, and THOMAS J. MEYER
Appeal2017-009627
Application 14/479,995
Technology Center 1700
Before CATHERINE Q. TIMM, JENNIFER R. GUPTA, and
MERRELL C. CASHION, JR., Administrative Patent Judges.
TIMM, Administrative Patent Judge.
DECISION ON APPEAL 1
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellants2 appeal from the
Examiner's decision to reject claims 1, 2, and 4--14 under 35 U.S.C. § 103 as
1 In explaining our Decision, we cite to the Specification of Sept. 8, 2014
(Spec.), Final Office Action of July 7, 2016 (Final Act.), Appeal Brief of
Mar. 6, 2017 (Appeal Br.), Examiner's Answer of May 5, 2017 (Ans.), and
Reply Brief of July 4, 2017 (Reply Br.).
2 Appellants are the Applicants, The University of North Carolina at Chapel
Hill and North Carolina State University which are the real parties in interest
according to the Brief. Appeal Br. 3.
Appeal2017-009627
Application 14/479,995
obvious over Concepcion3 in view of Grinis4 and either of Panda5 or King. 6
We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.
The claims are directed to a photoharvesting complex. The complex
includes a first molecule chromophore 140 and a second molecule catalyst
150. Spec. ,r 28; Fig. 1. The Specification discloses an assembly of these
two molecules attached to a core/shell particle 130/120 that resides on a
substrate 110. Spec. ,r,r 27-28; Fig. 1. The core may be a nanoparticle of
tin-doped indium oxide (nanoITO) and the shell may be a thin layer of
titanium dioxide (Ti02) that resides on the core. Spec. ,r 28; Fig. 1.
The photoharvesting complex is used in a Dye Sensitized
Photoelectrosynthesis Cell (DPEC). Spec. ,r 6. The complex harnesses light
energy to split water into H2 and 02. Spec. ,r 3. According to the
Specification, the chromophores absorb light, such as by the sun 160,
resulting in a Metal-to-Ligand Charge Transfer (MLCT) excited state that
injects an electron 170 into the conduction band of the metal oxide shell 120.
Spec. ,r 28; Fig. 1. The injected electron 170 rapidly undergoes transfer to
the transparent conductive oxide core (nanoITO) 130 and to the
3 "Catalytic and Surface-Electrocatalytic Water Oxidation by Redox
Mediator-Catalyst Assemblies," Angewandte Chemie 48(50), pp. 9473-
9476, December 2009.
4 "Collector-Shell Mesoporous Electrodes for Dye Sensitized Solar Cells,"
Israel Journal of Chemistry 48(3-4), pp. 269-275, December 2008.
5 "Nanoscale size effect of titania (anatase) nanotubes with uniform wall
thickness as high performance anode for lithium-ion secondary battery,"
Journal of Power Sources 204, pp. 162-167, April 2012.
6 "Ti02 Inverse Opals Fabricated Using Low Temperature Atomic Layer
Deposition," Advanced Materials 17(8), pp. 1010-1013, April 2005.
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Appeal2017-009627
Application 14/479,995
substrate 110. Spec. ,r 28. The catalyst 150 transfers an electron 192 to the
chromophore 140, whereupon the catalyst 150 can oxidize water. Id.
Appellants' photoharvesting complex uses a Ti02 shell of small
thickness, i.e., not greater than about 5 nm. Claim 1 is illustrative:
1. A photoharvesting complex comprising:
a transparent conductive metal oxide core;
a metal oxide shell having a thickness not greater than
about 5 nm,
wherein the metal oxide shell comprises Ti02;
a first molecule chromophore; and
a second molecule catalyst.
Appeal Br. 17 (claims appendix) (emphasis added).
OPINION
The issue on appeal is: Have Appellants identified a reversible error
in the Examiner's finding of suggestion within the prior art for creating a
photoharvesting complex with a Ti02 shell that is less than 6 nm thick?
Appellants have identified such an error.
The Examiner finds that Concepcion teaches a photoharvesting
complex comprising a first molecule chromophore and a second molecule
catalyst. Ans. 2. Concepcion anchors those molecules to a film of Ti02
nanoparticles on fluorine doped tin oxide (PTO). Concepcion 9475, first full
para. As recognized by the Examiner, the film configuration is not disclosed
as a core/shell configuration. Ans. 2. Thus, the Examiner relies on Grinis
for the core/shell configuration.
Grinis teaches a dye-sensitized solar cell (DSSC) that uses dye
molecules to generate electric current. Grinis 269, col. 1-2. As the
Examiner finds, Grinis teaches a core/shell configuration in which Ti02 is
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Application 14/479,995
coated onto a matrix of transparent conductive oxide (TCO) particles of, for
instance, ITO. Grinis 270, col. 1, 3rd full para., Fig. 1. But Grinis teaches
the shell must be at least 6 nm thick so the Examiner further relies on Panda
and King to support a determination that it would have been obvious to form
thinner shells within the "not greater than about 5 nm" range of claim 1.
Ans. 2-3.
The Examiner does not dispute that Grinis teaches away from using 5
nm thick Ti02 shells as argued by Appellants. Ans. 4. The Examiner's
rejection rests on the finding that Grinis teaches that coatings less than 6 nm
thick are amorphous and non-semiconducting and that Panda and King
provide a suggestion of using a different coating deposition method ( atomic
layer deposition (ALD)) that would allow one to form a crystalline
semiconducting Ti02 shell at thicknesses as low as 2 nm. Ans. 2-5. The
Examiner reasons that the ordinary artisan would have used ALD as taught
by either of Panda or King to form the shell of Grinis in order to obtain films
as little as 2 nm thick in order to allow for the use of smaller ITO
particles/pores and to form a uniform coating so that the electrode is
uniformly coated. Ans. 3.
The Examiner's rationale is not supported by the references.
Grinis specifically teaches that the Ti02 coating must be more than
6 nm thick and this thickness is not solely based on the fact that coatings less
than that thickness will be amorphous and non-semiconducting. In fact,
Grinis is concerned with recombination rate. Grinis teaches a high surface
area electrode with porous geometry. See Grinis Fig. 1 ( conductive
mesoporous matrix of TCO coated with Ti02). The use of such a high
surface area electrode introduces a problem: The collection of the
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Application 14/479,995
photoinjected electrons competes with recombination reactions. Grinis 270
col. 1, 1st full para. The purpose of the Ti02 shell is to serve as an energy
barrier that reduces the recombination rate reaction processes. Grinis 270
col. 1, 1st to 3rd full paras. Grinis reports that previous experiments revealed
that electrodes performed poorly when the Ti02 layer was less than 6 nm
"due to the fast recombination rate." Grinis 270, sentence bridging cols. 1-
2. Grinis aims to create a conformal, compact, and uniform Ti02 shell with
a thickness of more than 6 nm to prevent losses due to recombination
processes. Grinis 272 col. 2, 2nd and 3rd full paras.
Contrary to the Examiner's finding (Ans. 4), Grinis does not teach
that it is the amorphous nature of the Ti02 shell that limits the thickness to
greater than about 6 nm. This becomes clear from an understanding of
Grinis' discussion of the experiments Grinis conducts and their results.
To conduct the experiments, Grinis forms a Ti02 shell by sol-gel
electrophoretic deposition (EPD) to form electrode 2. Grinis 271, para.
bridging cols 1-2. The thickness of the Ti02 shell varies from 1.5 to
40 nanometers due to non-uniform coating. Grinis 272 col. 1, discussing
Figure 3. Grinis sinters the sample at 500 °C for 30 minutes. Id.
Grinis reports that Figure 3c shows one of the obtained structures. Id.
Grinis states this Figure 3c structure is optimal and has a conformal Ti02
shell of 8-9 nm thickness. Id. The Figure 3c shell consists of small 3-7 nm
crystalline titania particles and is covered by a continuous amorphous Ti02
layer.
Figure 3d is a view of a part of two ITO particles coated with a 1.5-
2.5 nm thick Ti02 conformal layer. Grinis 273 Fig. 3.
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According to Grinis, the comparison of Figures 3c and 3d shows that
shells less than about 6 nm thick are amorphous whereas shells thicker than
6 nm consist of polycrystalline Ti02 particles grown on the ITO surface,
which are sometimes covered with an amorphous Ti02. Grinis 272 col. 1.
Grinis conducts further experiments by varying the sintering
temperatures and times and Figures 3e-f show the results. Grinis 272 col. 1.
Grinis reports that Figures 3e-f show individual crystalline Ti02 particles of
about 5-12 nm. Id. These particles did not contain an amorphous Ti02
layer. Grinis 272 col. 1 to the top of col. 2. Even though Grinis was able to
obtain fully crystalline Ti02 at 5 nm thickness, Grinis maintains that the
Ti02 shell should be more than 6 nm in thickness. Grinis 272 col. 2, 1st full
para.
Whether the Ti02 is amorphous or crystalline, Grinis teaches the shell
must be at least 6 nm thick. There is no suggestion within the prior art for
looking to another coating process, such as atomic layer deposition (ALD),
to form Ti02 shells of less than 6 nm thick.
Appellants have identified a reversible error in the Examiner's
rejection.
DECISION
The Examiner's decision is reversed.
REVERSED
6