Exploring Electrochemical Technology: A Perspective on the ASEE/NSF Small Business Postdoctoral Research Diversity Fellowship

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1 Proceedings of 2014 Zone 1 Conference of the American Society for Engineering Education (ASEE Zone 1) Exploring Electrochemical Technology: A Perspective on the ASEE/NSF Small Business Postdoctoral Research Diversity Fellowship Julie N. Renner and Kathy E. Ayers Abstract The American Society for Engineering Education administers a postdoctoral fellowship program supported by the National Science Foundation, encouraging PhD recipients to conduct research in small businesses for 1-2 years. This is a relatively new and unique program where the fellow gains valuable hands-on industry experience while simultaneously small companies enjoy PhD-level work at an affordable cost. To date, the official website is the sole source of public information about this program, with very few first-hand experiences described. This paper summarizes the research and professional activities of a postdoctoral fellow working for Proton OnSite, a leader proton exchange membrane (PEM) water electrolysis systems. The information will help graduate students make educated career decisions. Index Terms electrochemical devices, multidisciplinary engineering, small business, women in engineering. I. INTRODUCTION ndustrial positions constitute a small percentage of the Ipostdoctoral workforce. A 2008 NSF InfoBrief estimated 8% of engineering postdocs worked in for-profit or nonprofit companies or organizations. 1 While data on industrial postdocs is scarce, the experience offers a variety of potential benefits including exposure to team-oriented and collaborative environments, access to industry contacts and resources, and the opportunity to gain managerial experience. 2 In addition, industry postdoctoral positions come with financial benefits, sometimes including bonuses and stock options. While many of the above can also be attained in academia, postdoctoral positions in industry are often an overlooked option. The American Society for Engineering Education (ASEE) and the National Science Foundation (NSF) have created a program to support postdoctoral training in small businesses. 3 Companies with active Phase II Small Business Innovation Research (SBIR) awards are eligible to participate. Fellows Manuscript received February 18, This material is based upon work supported by the National Science Foundation under Grant # IIP to the American Society for Engineering Education. K. E. Ayers is with Proton OnSite, 10 Technology Drive, Wallingford, CT USA. Phone: ; fax: ; [email protected]. J. N. Renner is with Proton OnSite, 10 Technology Drive, Wallingford, CT USA. [email protected]. write research proposals for the small business to review before accepting them into the program. Companies benefit financially, paying only a modest amount toward the fellow s stipend and for a small administrative fee, while fellows have the opportunity to participate in industrial research. Fellows are assigned a mentor at the company, and semi-annual reporting is required throughout the fellowship to document progress made toward project goals. The program offers many special advantages. Fellows come with their own funding, which can allow them some freedom to explore their own research topics and learn techniques in a new field. Additionally, the required mentorship ensures fellows are getting adequate support, while simultaneously ensuring that the company expectations are satisfied. Finally, because the fellow is in a smaller company, they have the opportunity to be a part of different aspects of the business, including but not limited to manufacturing, quality control, sales, business development, and customer service. One of the program goals is to recruit postdoctoral candidates from underrepresented groups to work in small businesses.3 Minority groups are underrepresented in postdoctoral positions, 4 and women are underrepresented in industry management positions. 5 This article outlines the experience of one female postdoctoral fellow working for Proton OnSite, located in Wallingford, CT. Proton OnSite is the world leader in proton exchange membrane (PEM)-based electrolysis systems, and is well-established in the marketplace for industrial applications. Postdoctoral activities including research, mentoring, management, proposal writing and networking are described. The information will provide context for the type of experience that can be gained in an industry postdoctoral position, and will better equip students to make career decisions upon graduating. II. RESEARCH AND DEVELOPMENT The research fellow was given the opportunity to be highly involved with catalyst studies at Proton OnSite as well as proof-of-concept experiments to support proposal writing activities. A summary of the major results from these activities is presented below. A. Catalyst Fundamentals The fellow worked with the production team to audit the catalyst processing techniques at Proton OnSite and identify /14/$ IEEE

2 important parameters. It was hypothesized that catalyst surface charge had a significant impact on the characteristics of the resulting material. A simple and inexpensivee titration method was employed to screen surface charge. 6 Exploring effects of the extreme cases, it was found that catalysts which caused a large basic shift in ph also resulted in different morphology and processing behavior compared to catalyst with an acidic shift (Fig. 1). Fig. 3. Polarization curves showing that acid treatment of catalyst does not affect initial performance compared to Proton s baseline. Fig. 1. Mass titration curves showing extremes of catalyst surface charge. Based on these results, a technique was explored to control the charge on the catalyst particles. A catalyst lot with high base contamination was subjected to an acid treatment and rinsed. Titrations of the treated lot indicatedd that the charge could be changed and the processing behavior could be controlled. In a separate experiment, Brunauer-Emmett-Teller (BET) analysis indicated that after the acid treatment the catalyst had a negligible decrease in surface area (less than 5%). Scanning electron microscope (SEM) images were taken of the base contaminated catalyst, and of the same catalyst treated with acid (Fig. 2). Both samples were dried and sifted with the same protocol. Fine particles are reduced after the acid treatment. Fig. 2. SEM images showing fine catalyst particle size (left) before acid treatment and larger particles after acid treatment (right, same magnification). The performance of a membrane electrode assembly (MEA) manufactured with acid treated catalyst was evaluated in a 25 cm 2 test cell at 50 C and compared to Proton s baseline data (Fig. 3). The results indicate that the performance is not affected by the acid treatment of the catalyst. The impact of the research includes an inexpensive screening technique which prevents catalyst lots with suboptimal surface charge from entering the processing pipeline. This research also demonstrated control the surface charge for future processing needs. B. Electrodes for Low-Cost, Alkaline Exchange Membrane (AEM)-based Water Electrolysis Over the past decade it has been realized that anion exchange membranes (AEMs) can be used as a solid state electrolyte, enabling AEM fuel cells and other devices. 7 Compared to PEMs, the technology is less developed, but AEMs are advantageous because they 1) enable low-cost materials of construction, 2) they allow the utilization of a wider array of low-cost catalysts, and 3) in Proton s experience, AEM materials are stiffer and easier to handle than PEM membranes of similar thickness. This makes AEMs more robust to normal processing than PEM materials, and therefore thinner membranes can be used. Because of these distinct cost advantages, efficiency penalties due to AEMs having intrinsically lower ion conductivity are expected to be mitigated. It is for these reasons AEM development is included in Proton s technology roadmap. Currently, there are no viable alternatives to noble metal- Proton works with based catalysts in PEM-based electrolysis. a variety of academic partners (for example, Illinois Institute of Technology and Northeastern University) who investigate AEM technology and appropriate catalysts. However, catalyst activity and stability, electrode structure and manufacturing are all still active areas of research. Since AEMs have a lower heat tolerance than PEM materials, traditional heating and pressing to make MEAs will not work. In this work, the fellow had the opportunity to independently conceptualize and explore a solution-based metal deposition technique for AEMrequire excessive heating, based electrolysis, which does not or pressing. To Proton s knowledge, this is the first time this technique has been explored for this specific application. Cobalt-based catalyst was directly plated on anode gas diffusion layers (GDLs) to make gas diffusion electrodes (GDEs). These GDE samples weree built in a 5 cm 2 test cell with a standard noble metal electrolysis cathode. Testing was conducted at 50 C in an anode feed configuration. The non- initial performance to noble metal electrode showed similar the standard noble metal electrode, demonstrating proof-of- (Fig. concept for the deposition techniquee 4).

3 Fig. 4. Cobalt-based anodes have performance similar to the noble metal baseline. Scanning electron microscope (SEM) images were taken of the cobalt-based electrodes (Fig. 5). EDS was employed to ascertain the chemical nature of the catalyst. The results show a hexagonal crystal structure, characteristic of cobalt. Energy- cobalt dispersive X-ray spectroscopy showed distinct peaks. Fig. 5. SEM image showing the hexagonal crystal structure of cobalt-based catalyst. This research shows a feasible pathway for AEM electrode manufacturing, using inexpensive catalyst materials. This work has been included in proposals aiming to advance AEM technology. C. Low-Cost Alkaline Exchange Membranee (AEM)-based Electrochemical Ammonia Production The Haber Bosch process is the main route for ammonia (NH 3 ) production, combining nitrogen (N 2 ) with hydrogen gas (H 2 ). The strong triple bond and unreactive nature of N 2 contributes to a low equilibrium conversionn (~15%) and the requirement of high pressure ( atm) and high temperature ( C) to form NH 3. This process is energy intensive, and typically uses either coal or natural gas as the energy and hydrogen feed stock. In addition, the capital cost for Haber-Bosch ammonia production plants is prohibitive for small, point-of-use plants increasing the energy consumed and related greenhouse gas emissions via shipping. Electrochemical production of ammonia has many benefits because it decreases the need for pressuree and heat, 8 and allows oxidation and reduction reactions to be separated, enabling a wider range of chemistries and potentially more selective catalysts for each reaction. This flexibility in chemistries and catalysts may eliminate the need to use highly purified inlet streams, potentially allowing air to be the N 2 source. In addition, because electricity is used to drive the reactions, integration with renewable energy sources (e.g. wind or solar) becomes more plausible. There are several papers nvolving electrochemical production of ammonia. 9 PEMs are well-established and have been recently incorporated into a number of ammonia synthesis devices. 10 However, the reported performance is low and can be partly attributed to the need for selective catalysts. One problem with using PEM-based devices is the acidic environment limits durable catalyst options to expensive noble metals. In addition, ammonia is a weak base, and it is expected that it readily reacts with acidic membranes to reduce proton conductivity and speculatively, membrane lifetime. Recently, AEMs have been successfully demonstrated in ammonia fuel cells, 11 but there is no significant published work on AEM utilization for ammonia synthesis to date. The fellowship allowed access to multiple experts in cell design and exploratory work to take place proving an AEM-based ammonia production cell is feasible. An AEM-based ammonia production cell was designed and built for proof-of-concept experiments. Fig. 6 shows the schematic of the electrochemical cell. The feed gas stream is humidified nitrogen gas. The N 2 and water (H 2 O) present in the feed stream combine with electrons at the cathode to form hydroxide ions (OH-) and ammonia. The key enabler in the device is the AEM which selectively conducts OH- to the anode where the ions form oxygen (O 2 ) and H 2 O. The end result is an ammonia enriched stream depleted of small amount of N 2 and H 2 O. Electrolysis catalysts were used, which were neither selective to ammonia nor optimized for stability but served as a proof-of-concept demonstration. Fig. 6. Schematic for AEM-based ammonia production cell. Polarization data showed current was achieved at potentials lower than the water electrolysis theoretical voltage in the initial performance test (Fig. 7). This is evidence that ammonia production is occurring. Degradation of performance was apparent with the earliest curve having the best performance, and an increase in activation energy occurring as the cell is operated. Samples taken during the initial testing period and after several hours of operation were analyzed for ammonia content using a colorimetric assay. 12 The assay shows that the AEM-based technology is capable of producing ammonia (Fig. 8).

4 Fig. 7. Polarization data of an AEM-based ammonia production cell. The results not only show that the novel AEM-based technology is credible, but also provide direction for future development activities. The data indicate that faradaic efficiency needs to be improved and a more selective and stable catalyst is required on the ammonia production side of the cell. Fig. 8. Ammonia produced in AEM-based electrochemical cell. These results have supported multiple proposals, showing, proof-of-concept for a new and promising electrochemical cell design for ammonia production, as well as a direction for future development activities. III. SMALL BUSINESS EXPERIENCES A. Proposal and Report Writing The above results were included in multiple SBIR/STTR proposals where the technical write up was spearheaded by the fellow. The mentor provided feedback and scaffolding for the proposal writing effort. Through this effort, the fellow also had the opportunity to interact with academic partners to organize the scope and technical objectives of the proposals. This allowed the fellow to have guidance from professionals who have had experience and success in proposal writing. The fellow also supported government reporting activities for multiple SBIR projects. This was a synergistic role, providing the company with project support in a concrete way, but also exposing the fellow to multiple technologies in a short amount of time. B. Small Business Upper Management Exposure In the first year of the fellowship, the research mentor organized one-on-one interviews with the research fellow and the upper management at Proton OnSite. During the interviews, the research fellow learned what the person s role was at the company. The fellow was encouraged to ask detailed questions about the importance of the role, including how the role was executed, what experiences helped them in their career, and if they had any advice for the fellow. This effort has fostered a greater understanding of how a small business operates and how each part of the company fits into the overall vision. C. Project Management and Team Building The research mentor encouraged the fellow to assume a Project Manager role in a Phase II STTR with Brookhaven National Labs which investigates alternative electrode manufacturing and core-shell catalysts to reduce the noble metal content by an order of magnitude in proton exchange membrane (PEM)-based water electrolysis. The research fellow s responsibilities includedd collaborating with the investigators at Brookhaven, managing and prioritizing project tasks, organizing team meetings and providing direction to engineers to achieve the milestones of the project. The research fellow was also encouraged to travel to Brookhaven to meet the collaborators, and attend a symposium to further establish a network. In addition, the research fellow was asked to be part of multiple teams in a technical support role by conducting laboratory experiments, supporting government reporting activities, acting as an academicc liaison, and providing technical guidance to engineers. This experience provided a broad technical exposure, while simultaneously building a teamwork mentality within the company culture. D. Mentoring The research fellow also had the opportunity to mentor multiple undergraduate interns with industry-based research projects. The fellow was responsible for defining the project plans for these students, as well as managing their activities and tracking their progress. The fellow spearheaded a co-op program with the University of Connecticut Department of Chemical and Biomolecular Engineering, where students participate in defined industry-based projects for credit. The program is being piloted this spring, with two students participating. One student is working on identifying and developing new catalyst characterization techniques to understand catalyst processing behaviors. The end result will be official company work instructions for the techniques developed. Another student is designing, building and testing an electrodeionization unit using Proton hardware. The end result of this project will be proof-of-concept data to be included in future research proposals or publications.

5 E. Networking Financial assistance is given to the fellow through the fellowship program to attend conferences, allowing the fellow to travel at a significantly reduced cost to the company. The fellow was able to meet academic partners who later became collaborators on proposals. Additionally, the fellow interfaced with local universities to understand current research and potential future collaborations, as well as equipment and testing capabilities. IV. CONCLUSIONS While industry postdocs are relatively rare, this report demonstrates the experience can include many professional advantages, including the opportunity to conduct cutting edge research, write proposals, manage projects, direct research, obtain valuable contacts, and understand business structure. Postdocs can have a tangible positive impact on companies by supporting manufacturing, and can also have long term impact by developing emerging technologies. Commun., vol. 17, pp , Jul [9] I. A. Amar, R. Lan, C. T. G. Petit and S. Tao, "Solid-state electrochemical synthesis of ammonia: a review," J. Solid State Electrochem., vol. 15, pp , Sept [10] R. Lan, J. T. S. Irvine and S. Tao, "Synthesis of ammonia directly from air and water at ambient temperature and pressure," Scientific Reports, vol. 3, pp. 1-7, Jan [11] R. Lan, J. T. Irvine and S. Tao, "Ammonia and related chemicals as potential indirect hydrogen storage materials," Int. J. Hydrogen Energy, vol. 37, pp , Jan [12] F. Koroleff, Determination of nutrients: 2. Ammonia, in Methods of seawater analysis, K. Grasshoff, Ed. 1976, pp ACKNOWLEDGMENT The authors would like to thank the employees at Proton OnSite including Chris Capuano, Luke Dalton, Mike Niedzwiecki, Morgan George and Judith Manco for the intellectual discussions. Mike Niedzwiecki specifically obtained the SEM images presented throughout the document. REFERENCES [1] T. B. Hoffer, K. Grigorian, and E. Hedberg, Postdoc participation of science, engineering and health doctorate recipients, NSF Directorate for Social, Behavioral, and Economic Sciences InfoBrief NSF Arlington, VA: National Science Foundation, March [2] G. H. W. Wong, Consider post-doctoral training in industry, Nat. Biotechnol. vol. 23, pp , Jan [3] NSF Small Business Postdoctoral Research Diversity Fellowship Program, Administered by: American Society for Engineering Education (ASEE). Dec. 04, Web. Feb. 12, < [4] P. Einaudi, R. Heuer, and P. Green, Counts of postdoctoral appointees in science, engineering, and health rise with reporting improvements, NSF Directorate for Social, Behavioral, and Economic Sciences InfoBrief NSF Arlington, VA: National Science Foundation, Sept [5] A. Sherrill, Women in management: Female managers representation, characteristics, and pay, United States Government Accountability Office GAO T. Sept [6] S. Zalac, and N. J. Kallay, Application of mass titration to the point of zero charge determination, J. Colloid Interface Sci., vol. 149, pp , Jul [7] J. R. Varcoe and R. C. T. Slade, "Prospects for alkaline anion-exchange membranes in low temperature fuel cells," Fuel Cells, vol. 5, pp , Oct [8] V. Kordali, G. Kyriacou and C. Lambrou, "Electrochemical synthesis of ammonia at atmospheric pressure and low temperature in a solid polymer electrolyte cell," Chem.