Summary of my undergraduate honors thesis chemical research I conducted. In this presentation, I give background to the significance of this research, a brief review of previous research done in the field, report the findings of this study, deliver several conclusions of the study, and propose further work that can be conducted in this research area.

1. MODIFYING A CARBON MONOXIDE
(CO) FUEL CELL PROTOTYPE: CO
OXIDATION IN BASIC SOLUTION
CATALYZED BY NICKEL COMPLEXES
Ilan Hirschfield

2. Outline
■ Background
■ Previous Studies
■ This Study
■ Conclusions

3. Background:
Fossil Fuels Vs. Fuel Cells
■ Future of fossil fuels and internal combustion engines (ICEs)
– Environmental concerns
– Long-term economic/political ramifications
■ Fuel cells
■ H2, CH3OH
■ Oxygen Reduction Reaction (ORR)
■ CO

4. Background:
Fuel Cell Structure
Fig. 1. Hydrogen fuel cell design
Source: ”Thermodynamic Efficiency of Hydrogen Fuel
Cells”, MECH Tech. YouTube. Video. Accessed 16 June 2022
• Precious metal cost for
catalyst
• Pt
• ORR kinetics (sluggish)

5. Background: Examples
Fig. 2. Toyota Mirai: H2 Fuel Cell
Electric Vehicle (FCEV)
Source: “Preview: 2021 Toyota Mirai” Motor Authority.
Web.
https://www.motorauthority.com/news/1130013_2021-
toyota-mirai-price-specs-review-photos-info. Accessed 19
June 2022.
Fig. 3. General Motors (GM)
Chevrolet Equinox Fuel Cell: H2
FCEV
Image Source: “General Motors Hydrogen4 - Chevrolet
Hydrogen Fuel Cell Equinox Prototypes 2008”.
AutoConcept-Reviews. Web. http://www.autoconcept-
reviews.com/cars_reviews/gm/GM-hydrogen4-chevrolet-
hydrogen-fuel-cell-equinox-2008/cars_reviews-gm-
hydrogen4-chevrolet-hydrogen-fuel-cell-equinox-

6. Previous Work:
Humble Beginnings
■ Windsor, M. M.; Blanchard, A. A. Nickel Carbonyl. A Study of the Mechanism of
Its Formation from Nickel Sulfide and Carbon Monoxide. Journal of the
American Chemical Society 1933, 55 (5), 1877–1883.
– Observed reduction of Ni2+ sulfide or cyanide by carbon monoxide (CO)
under basic conditions to form Ni(CO)4
■ Hirsch, E.; Peters, E. Canadian Metallurgical Quarterly 1964, 3 (2), 137–151.
– Studied kinetics of oxidation of CO by Ni-amine complexes
– Mechanism:
Ni(NH3)+CO+OH−→[(NH3)−Ni−CO−OH]+4CO→Ni(CO)4+CO2+NH4+

7. Previous Work:
Progress
■ Jasinski, R. Nature 1964, 201 (4925), 1212–1213.
– Synthesis of Co-Phthalocyanine catalyst capable of reducing O2 in basic
conditions
Fig. 4. Synthetic relationship between phthalocyanine and
porphyrin.
Source: “Phthalocyanine” Wikipedia. Web.
https://en.wikipedia.org/wiki/Phthalocyanine Accessed 19

8. Previous Work:
Expanding The Canon
■ Gewirth, A. A.; Thorum, M. S. Electroreduction of Dioxygen for Fuel-Cell
Applications: Materials and Challenges. Inorganic
Chemistry 2010, 49 (8), 3557–3566.
– Markovic and co-workers used a Ni/Pt alloy of nanoparticles as the
catalyst for a proton exchange membrane fuel cell
■ Lo, W.; Hu, C.; Lumeij, M.; Dronskowski, R.; Lovihayeem, M.; Ishal, O.; Jiang,
J. [CoI(CN)2(CO)3]−, a New Discovery from an 80-Year-Old Reaction. Chemical
Communications 2013, 49 (67), 7382. https://doi.org/10.1039/c3cc43269f.
– Synthesis of two new novel Co1+ complexes w/mixed CO/cyanide (CN)
ligands under CO atmosphere

9. Previous Work:
Expanding the Canon
Fig. 5. ORTEP drawing of [CoI(CN)2(CO)3] (left) and
[CoI(CN)3(CO)2] (right) at the 50% ellipsoid level.
Source: Lo, W.; Hu, C.; Lumeij, M.; Dronskowski, R.; Lovihayeem, M.;
Ishal, O.; Jiang, J. [CoI(CN)2(CO)3]−, a New Discovery from an 80-Year-
Old Reaction. Chemical Communications 2013, 49 (67), 7382.
https://doi.org/10.1039/c3cc43269f.

10. Previous Work:
Further Expansion and Prototype Development
■ Chem. Commun., 2015, 51, 9432
– Jiang and co-workers expanded 2013 study and synthesized Ni0 cyano-
carbonyl complexes
– Used these Ni complexes to catalyze CO oxidation, reversible upon
addition of base to mixture under CO atmosphere
Fig. 6. ORTEP drawing of [Ni0(CN)(CO)3]- (left) and
[Ni0(CN)2(CO)2]2- (right) at the 50% probability level.
Source: Chem. Commun., 2015, 51, 9432

11. Previous Work:
Why CO?
Fig. 7. Catalytic cycle depicting CO oxidation
Source: Chem. Commun., 2015, 51, 9432
■ CO as reducing agent
– Nearly same energy content as H2
volume-wise in gas phase
(Bond dissociation energy = 1072 kJ/mol)
– Precedents in literature
Fig. 8. Two primitive CO-powered fuel cells
Source: Chem. Commun., 2015, 51, 9432

12. This Study:
Hypothesis
■ Optimize reaction conditions for conducting this chemistry
– Temperature
– Base concentration
– Solvent
– Ligand choice - safety

13. This Study:
Experimental Design
■ Criteria for ligands of choice in investigation
– Bind effectively to Ni
– Minimize steric hindrance for CO oxidation
■ Ligands chosen
– Phosphines (PR3)
– Ammonia (NH3)
– Tetra-amines

14. This Study:
Ligands Used
PPh3
Tetra-amine
#2: 2,3,2-N2,
Tetra-amine #1:
3,2,3-N2, N2
1,2-
bis(diphenylphosphinoethan
e) (dppe)
Ammonia

15. This Study:
Experimental and Analytical Setup
Fig. 9. Synthetic experimental setup
Source: Chem. Commun., 2015, 51, 9432
Fig. 10. Fourier-Transform Infrared
(FTIR)
Spectrometer

16. This Study:
Experimental Design
■ All syntheses in this study took place under aqueous conditions and 1 atm CO
atmosphere
Ligand (mmol) NiCl2*6H2O (mmol) NaOH (mmol) Dichloromethane
(mL)
PPh3, 1.00 ~1.00 ~50 (excess) 30
dppe, 1.00 ~1.00 ~50 (excess) 30
NH3, 1.00 ~1.00 ~50 (excess) 30
3,2,3-N2, N2, 1.00 ~1.00 ~50 (excess) 30
2,3,2-N2, N2, 1.00 ~1.00 ~50 (excess) 30

17. This Study: Results
Ligand Initial Observations Final Observations
(48-72 hrs)
Change in quantity
of CO present
PPh3 Colorless sol’n,
green precipitate
Colorless sol’n,
white precipitate
Decrease
1,2-
bis(diphenylphosphin
oethane) (dppe)
Cloudy orange sol’n,
no precipitate
Light orange sol’n,
some white
precipitate
Decrease
NH3 Purple/blue
homogeneous sol’n,
no precipitate
Purple/blue
homogeneous sol’n,
no precipitate
No change
3,2,3 – N2, N2 Purple homogeneous
sol’n, no precipitate
Colorless sol’n,
white precipitate
Unsure
2,3,2 - N2, N2 Purple homogeneous
sol’n, no precipitate
Colorless sol’n,
white precipitate
Unsure

18. This Study:
Results and Discussion
■ Increase in reaction temperature and base concentration led to quicker CO
volume decrease
– ~10%
■ Use of PPh3 as ligand led to significant CO volume decrease
– Very slow, inefficient due to heterogeneity of conditions

19. This Study:
Results and Discussion
■ Use of dppe as ligand led to significant CO volume decrease
– Quicker than PPh3,
– No Ni0[dppe](CO)2 IR spectroscopic data
■ Use of NH3 led to no CO volume decrease
– No consumption of CO (oxidation), verified by lack of color change
■ 3,2,3-N2, N2 led to significant CO volume decrease
– Quicker than PPh3, single peak observed on IR @ 2040 cm-1

20. Conclusions
■ Increasing temperature and base concentration decreased reaction time
■ dppe and 3,2,3-N2, N2 show encouraging progress as ligand alternatives to CN-
for using Ni complexes to catalyze CO oxidation
■ Future studies
– PPh3 and NH3 failure
– IR data for Ni0[dppe](CO)2
– Crystallographic data for dppe-Ni0 and tetra-amine-Ni0 complexes
– Alternate ligands

21. Acknowledgements
■ Prof. Jianfeng Jiang (JJ)

22. Thank you