Renewable Energy Global Innovations features: MnO-Co Composite Modified Ni-SDC Anode for Intermediate Temperature Solid Oxide Fuel Cells

Significance Statement

Fuel cells have the ability to convert chemical energy in fuels to electric energy without the inhibition of the Carnot cycle. Conventional power generating devices are deficient in efficiency, low emissions and the potential for combined heat and power generation, critical features among which the fuel cell vehemently manifests. Solid oxide fuel cells (SOFCs) often operate at high temperatures which contributes to a higher efficiency and power density as compared to other types of fuel cells. More so, the high operating temperatures enable the SOFCs to utilize carbon monoxide as a fuel rather than a poison. SOFCs with Ni-YSZ (yttria-stabilized zirconia) cermet anodes often operate at a higher temperature which translates into higher synthesis cost. Conversely, SOFCs with Ni-SDC (samarium-doped ceria) cermet anodes have exhibited lower operating temperatures and excellent electrochemical performance at intermediate temperatures. Besides, efforts are still needed so as to promote the performance and stability of SOFCs of Ni-SDC anodes in hydrogen and/or methane.

Zhonghua Zhu and his group at The University of Queensland in Australia, proposed studies to enhance the electrochemical performance and/or stability of Ni-SDC anode in hydrogen and/or methane. The authors firstly modified the Ni-SDC anode with manganese oxide and cobalt (MnO-Co) composite in a bid to further promote its performance. The research team begun their empirical work by ball-milling NiO, SDC, dextrin (pore former) and synthesized manganese-cobalt spinel in ethanol for a specific period. They then prepared the anode-supported solid oxide fuel cells. The crystal structures of the synthesized powders and anode powders were characterized by x-ray diffraction. The microstructure of the fabricated solid oxide fuel cells was also examined by scanning electron microscopy.

After the successful fabrication of the Ni-SDC and MnO-Co composite modified Ni-SDC anode-supported SOFCs, the authors observed that when compared with the normal Ni-SDC anodes, the MnO-Co modified Ni-SDC anodes exhibited much higher peak power density and lower polarization resistance in dry hydrogen gas and dry methane gas at all of the temperatures investigated. The modified anode had higher porosity than the original anode. However, the team noted that the stability of MnO-Co modified Ni-SDC anodes was worse than that of Ni-SDC anodes in dry methane due to severer carbon deposition. This research work is now published in Fuel Processing Technology.¹ After that, the authors applied a MnO-Co-SDC internal reforming layer over the Ni-SDC anode and observed significant improvement in its performance and stability in wet methane (3mol% H₂O in methane). They found that the anode started to decline in 150 minutes without the reforming layer, but showed no indication of degradation over 900 minutes due to the methane pre-reforming process after the addition of the MnO-Co-SDC layer at 0.2A/cm² and 650 ^oC and the peak power density was further increased by over 10%. This work has been published in Journal of Materials Chemistry A.² On-going research is being carried out in Prof Zhu’s group.

Reference

• Jie Zhao, Xiaoyong Xu, Wei Zhou, Zhonghua Zhu. MnO-Co composite modified Ni-SDC anode for intermediate temperature solid oxide fuel cells. Fuel Processing Technology, volume 161 (2017) pages 241–247.

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• Jie Zhao, Xiaoyong Xu, Wei Zhou, Zhonghua Zhu. An in situ formed MnO–Co composite catalyst layer over Ni–Ce₈Sm_0.2O_2-x anodes for direct methane solid oxide fuel cells. Journal of Materials Chemistry A, volume 5 (2017) pages 6494-6503.

 

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Renewable Energy Global Innovations features: Synthesis of inorganic-organic hybrid membranes consisting of organotrisiloxane linkages and their fuel cell properties

Significance Statement

Perfluorosulfonic polymers, for instance, Naflon, are preferable candidates for membranes used in polymer electrolyte fuel cells owing to their high proton conductivity, excellent mechanical strength, and chemical stability for temperatures below 100°C.  Nevertheless, the operating conditions need to be optimized to maintain 100% relative humidity at about 80 °C as well as low carbon-monoxide concentration in hydrogen gas. The functioning of polymer electrolyte fuel cells at higher temperatures raises the tolerance concentration of carbon monoxide poisoning for the platinum catalysts.

The increased operation temperature enhances the cell efficiency and simplifies the management system. For this reason, there is an urgent need for membrane electrolytes exhibiting high proton conductivities as well as intermediate temperatures. Inorganic-organic hybrid membranes possess the advantages of inorganic as well as organic phases. This is in the sense that functionality and flexibility of organics are blended with the thermal, mechanical, and chemical stability of inorganics. Therefore, the inorganic-organic hybrid membrane is preferable for implementation at intermediate temperatures.

Copolymerization of suitable monomers is a clear-cut approach for the formation of covalent bonds in the hybrid membranes. Researchers led by Professor Toshinobu Yogo at Nagoya University in Japan, demonstrated the one-pot synthesis of inorganic-organic hybrid membranes through copolymerization of N-vinylbenzotriazole, 1,5-divinyl-3-phenylpentamethyltrisiloxane, and 2-hydroxyethyl methacrylate acid phosphate. The research team did not require any hydrolysis-condensation for the preparation of the silicon-oxygen-silicon linkages reference to the fact that trisiloxane linkage was used for the inorganic backbone of the hybrid membrane. Their research work is published in Polymer.

The authors adopted the ac impedance method to measure proton conductivity of the hybrid membranes. They did this at various temperatures and relative humidity in a sealed vessel. They equilibrated the measurement cell at a desired relative humidity for one night at about 40 °C before measurement.

The Toshinobu Yogo and his team constructed inorganic-organic membranes from trisiloxane as well as aliphatic polymer chains bond with phosphonic acid groups, which were later copolymerized through one-pot method. The authors observed that the membranes were self-standing, possessed high thermal stability, high formability, and were homogeneous. The trisiloxane linkage in the hybrid membrane enhanced the thermal and oxidation stability of the membrane.

The hybrid membrane in the ratio 1:9:5 was found to have a high elastic modulus as compared to that of membranes with 2:8:5 and 3:7:5. The proton conductivity of the hybrid membranes was observed to rise with increasing temperature and relative humidity up to 130 °C. 1:9:5-ratio membrane was operated at 140 °C, 30% relative humidity for about 30 hours and indicated a peak power of about 7.8mWcm^-2 at 10 hours. Reference to chemical design, one-pot synthesis of the hybrid membranes is presented as a versatile synthetic process for the polymer electrolyte fuel cells used at low relative humidity as well as intermediate temperatures.

About The Author

Masaya Takemoto received his B. Eng. (2013) and M. Eng. (2015) degrees in crystalline materials chemistry from Nagoya University. His research interests include processing and characterization of energy and energy-saving materials. Currently, he is working for an energy-related company.

About The Author

Koichiro Hayashi received the B. Eng. (2005), M. Eng. (2007), and Dr. Eng. (2010) degrees in materials chemistry from Nagoya University. He worked as an assistant professor at the Tokushima University (2010-2014) and Nagoya University (2014-2017). Currently, he is an assistant professor at Kyushu University.

His interests include the development of multifunctional organic-inorganic nanomaterials and their applications to medical and dental fields.

About The Author

Shin-ichi Yamaura is an Associate Professor at The Polytechnic University of Japan since 2015. He received his PhD degree from Tohoku University, Sendai, Japan in 1999. He worked as an assistant professor and as an associate professor in the Institute for Materials Research, Tohoku University from 2000 to 2015.

His research interests include the preparation, process, characterization and functional property of amorphous/nanostructured alloys for hydrogen-related applications and also grain boundary engineering focused on grain boundary character that can be described as CSL Σ-value.

About The Author

Wei Zhang is a Professor in School of Materials Science and Engineering at Dalian University of Technology, China. He received his PhD degree from Tohoku University (Japan) in 1998. He has been a Lecturer at Dalian University of Technology, a research fellow at Japan Science and Technology Agency, and an associate professor in Institute for Materials Research, Tohoku University.

His research interests include the preparation, processes, characterization, and properties of amorphous and nanostructured alloys. He has published more than 290 articles including 7 book chapters.

About The Author

Wataru Sakamoto is an associate professor at Institute of Materials and Systems for Sustainability, Nagoya University. He received B.S. and M.S. degrees in applied chemistry from Nagoya University in 1989 and 1991, respectively. He worked from 1991 to 1994 at Matushita Electric Industrial (now Panasonic) Co., Ltd. He earned his Doctorate of Engineering from Nagoya University in 2000. He was appointed an associate professor in the Center for Integrated Research in Science and Engineering (now named Institute of Materials and Systems for Sustainability), Nagoya University, in February 2002. His research interests are novel processing and properties evaluation of electroceramics and functional nanostructured materials.

About The Author

Toshinobu Yogo is a professor at Institute of Materials and Systems for Sustainability, Nagoya University. He received B.S. and M.S. degrees in synthetic chemistry from Nagoya University.  He received his PhD degree from Hokkaido University (Japan) in 1980.

His research interests include the synthesis and characterization of functional nanomaterials and nano-structured hybrid materials.

Reference

Masaya Takemoto, Koichiro Hayashi, Shin-ichi Yamaura, Wei Zhang, Wataru Sakamoto, and Toshinobu Yogo. Synthesis of inorganic-organic hybrid membranes consisting of organotrisiloxane linkages and their fuel cell properties at intermediate temperatures. Polymer, volume 120 (2017), pages 264-271.

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Renewable Energy Global Innovations features: Development of La(Cr,Co,Fe,Ni)O3 system perovskites as interconnect and cathode materials for solid oxide fuel cells

Significance Statement

Due to an increase in demand for sustainable energy sources, solid oxide fuel cells (SOFCs) have received more attention owing to their huge potential for power production in portal transport applications. Almost all solid oxide fuel cells are arranged either in parallel or series in order to facilitate voltage output. An interconnect is needed to connect the cells. It connects the cathode of one cell to the anode of the other, yet physically separates the cells.

An interconnect should be non-porous with 100% relative density to avoid the mixing of fuel and oxygen. Above all, it must be stable in oxidizing and reducing environments, have high electrical conductivity, chemical stability and sintering attributes. It can be metallic or ceramic. One desirable material for a ceramic interconnect in solid oxide fuel cell is the doped Lanthanum Chromite based perovskite material.

The cathode material should as well meet stringent requirements. Therefore, the shortcomings in perovskite oxide materials adopted for cathode and interconnect fabrication can be overcome through the synthesis of new materials by adding or modifying the transition metals in the current materials to enhance chemical stability, low sintering temperature, electronic and ionic conductivity, and thermal expansion coefficient.

Researchers led by Professor Rasit Koc at Southern Illinois University developed cathode and interconnect material for solid oxide fuel cells. Their main aim was to develop and evaluate cathode and interconnect materials for SOFC which will meet the exacting requirements of SOFC manufacturers.  These requirements are fabricability (sinterability) at temperatures 1400^oC and below at lower cost, high electronic conductivity, chemical stability in reducing and oxidizing conditions and coefficient of thermal expansion match with other cell components.  Dr. Zhezhen Fu of University of Maryland says “The developed sinterable materials with very high electrical conductivity are critical in the commercialization of low temperature solid oxide fuel cells (LT-SOFCs)”. The research work on La(Cr,Co,Fe,Ni)O₃ is now published in Ceramics International.

The authors prepared the powders through the Pechini approach. They mixed metal nitrates and lanthanum carbonate as starting materials in stoichiometric proportions. The resulting mixture was then mixed with ethylene glycol and citric acid forming a polymer that broke to form powder precursor. The precursors were calcined, ball milled, and pressed to form circular pellets. The microstructure developed completely in the course of the sintering process. The sintered samples were polished and thermally etched for microstructure analysis.

samples were prepared for electrical conductivity measurement. Each sample was subjected to resistance measurements. The pellets were then heated in a furnace and resistance measured as a function of temperature in the range of solid oxide fuel cell operation.

Through the Pechini polymer complexing approach, the authors were able to synthesize five compounds into a single phase of LaCo_0.7Cr_0.1Fe_0.1Ni_0.1O₃ (LCo7CFN), LaNi_0.7Cr_0.1Co_0.1Fe_0.1O₃ (LNi7CCF), and LaCr_0.25Co_0.25Fe_0.25Ni_0.25O₃ (LCCFN), LaFe_0.7Cr_0.1Co_0.1Ni_0.1O₃ (LFe7CCN), were sintered to a relative density of 98%, 82%, 94%, and 91% respectively at about 1400 °C for two hours in air. Transit liquid phases formed under the sintering conditions and contributed to the high relative densities. LaCr_0.25Co_0.25Fe_0.25Ni_0.25O₃ (LCCFN), posted the highest electrical conductivity.

Among the lanthanum perovskite oxides, LaCo_0.7Cr_0.1Fe_0.1Ni_0.1O₃ (LCo7CFN) and LaCr_0.25Co_0.25Fe_0.25Ni_0.25O₃ (LCCFN) appeared to comprise building blocks for interconnect fabrication owing to their high relative densities (94-98 %) and excellent electrical conductivity (>50 S/cm). LaNi_0.7Cr_0.1Co_0.1Fe_0.1O₃ (LNi7CCF) with high electrical conductivity and relative density of approximately 82% was selected to be a suitable candidate for the porous cathode.  Currently, these materials are being doped with Ca on the La site to further enhance their properties.

About The Author

Abhigna Kolisetty graduated from Southern Illinois University Carbondale with a Master’s degree in Mechanical Engineering. Her research interests are Material Science, clean energy, energy conservation, and energy efficiency. Under the guidance of her advisor, Dr Rasit Koc, Abhigna worked on developing interconnect and cathode materials for Solid Oxide Fuel Cells as her thesis topic. This research has been published in the journal “Ceramics International” as the article, “Development of La(CrCoFeNi)O₃ system perovskites as interconnect and cathode materials for solid oxide fuel cells.” She is currently a Mechanical Designer for AECOM, an engineering consulting firm in Cleveland, Ohio.

 

About The Author

Zhezhen Fu received his Ph.D. degree from Southern Illinois University in 2016. He is currently a Postdoctoral Associate at the University of Maryland. His research focuses on the processing and characterization of advanced ceramic materials such as: (1) titanium carbide and boride materials for structural application; (2) doped LaCrO3 perovskite for solid oxide fuel cell application; (3) lithium-ion conducting garnet-oxide for all-solid-state battery application.

About The Author

Dr. Rasit Koc is a Professor and Chair of Mechanical Engineering and Energy Processes (MEEP) Department at SIUC. Before coming to SIUC, Dr. Koc was a Senior Engineer at U.S. Department of Energy’s (DOE) National Renewable Energy Laboratory (NREL) in Golden, Colorado, where he conducted research in the areas of Processing and Characterization of Advanced Ceramic Materials and Composites. In 1995, his work on synthesizing nano-size SiC materials received R&D 100 award. During his graduate studies, he worked in cooperation with Dr. Harlan U. Anderson, in the areas of ceramic materials for Fuel Cells. Koc has authored/coauthored more than 100 papers and holds 3 U.S. patents. He served as the American Ceramic Society Rocky Mountain Chapter treasurer and he was an associate editor of the journal for 12 years.

Reference

Abhigna Kolisetty, Zhezhen Fu, and Rasit Koc. Development of La(Cr,Co,Fe,Ni)O₃ system perovskites as interconnect and cathode materials for solid oxide fuel cells. Ceramics International, volume 43 (2017), pages 7647–7652.

Department of Mechanical Engineering and Energy Processes, Southern Illinois University, 1230 Lincoln Drive, Carbondale, IL 62901, United States.

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Renewable Energy Global Innovations features: Polydopamine as a promising candidate for the design of high performance and corrosion-tolerant polymer electrolyte fuel cell electrodes

Significance Statement

Polymer Electrolyte Membrane Fuel Cells (PEMFCs) are considered to have potential as clean energy converters for future applications. There are huge cost considerations due to the usage of noble metal Pt which hinders its commercialization. To reduce the amount of Pt loading, Carbon with Pt nanoparticles is used but under harsh conditions in the PEMFC electrode, carbon materials and nanotubes degrade.

Researchers led by Dr. Marc Michel at Luxembourg Institute of Science and Technology used electrode structure made up of polydopamine (PDA) and carbon nanotubes in PEMFCs to enable the electrode to withstand the operating conditions arising in the fuel cell. The study is now published in Journal of Power Sources.

Polydopamine, among other advantages, is quite beneficial due to the presence of catechol and amino groups which leads to strong binding between PDA and Pt precursor. It promotes the conductivity of protons. Carbon nanotubes enhance the contact between the catalyst and the electrolyte as they form interconnected conducting networks. Thus, a structure having carbon nanotubes with Pt nanoparticles and coated with polydopamine was chosen for the research. This structure would save the carbon material from oxidation which occurs under the extreme operating conditions of the system.

The scientists prepared a new electrocatalytic active (Pt/MWNTs-PDA)₅₀ multi layered nanocomposite film with spray deposition which is much faster (100 times) than the conventional layer by layer (LBL) assembly. Two catalysts supports were prepared, one having multiwalled carbon nanotubes with Pt nanoparticles but without polydopamine as a reference, and the other wrapped with PDA. Physical characterisations were carried out using various methods (XPS, SEM, etc.) to realize the specifications for the experiment. The results yielded by the characterization showed the PDA covering of 19 %.

In their adsorption/desorption study of the catalyst in hydrogen and oxygen it was observed that the coating of PDA to the catalyst doesn’t affect the catalytic reactions. By Cyclic Voltammetry, the Electrochemical Charged Surface Area (ECSA) for Pt/MWNTs-PDA was found to be 15.2 m²/g(Pt) and for Pt/MWNTs was 10.3m²/g(Pt) for the first cycle. In subsequent cycles, the ECSA for the former was stable and degraded for the latter.

The polarization curves obtained show that the Pt/MWNTs-PDA has a lower open circuit voltage (OCV) than Pt/MWNTs. It is believed by the scientist that OCV will further decrease if PDA content is increased but it is yet to be experimentally confirmed. The concentration losses, on the other hand, shown by Pt/MWNTs-PDA are at higher current densities than that of Pt/MWNTs where the concentration losses start at an earlier current density of 1200 mA/cm². The concentration loss zones of the former are observed to be unstable at high current densities. The scientists infer that the instability might be due to some change in cathode structure.

The stability of the two catalyst supports were compared by continued cyclic voltammogram test. The conductivity of PDA-MWNTs was shown to be stable even after many cycles of operation as the surface resistance did not change. Also, the integral area of cyclic voltammograms for PDA-MWNTs did not change implying a good electrochemical stability. It was also observed, with the normalized plots, that the MWNTs would tend to corrode, and in comparison, PDA-MWNTs do not tend to corrode easily as they have the ability to decrease the overpotential of oxidation.

The research team was able to show that PDA-MWNTs are resistant to oxidation, and show a higher Pt Utilization of 6051 mW/mg which is three times as high as utilization obtained by MWNTs of the same Pt loading. PDA-MWNTs also show better performance based on the power densities observed. For the first time, they showed that polydopamine protects the electrode from corrosion of carbon.

To learn more about the research (EnergyCell)

 

About The Author

Dr. Marc Michel has a PhD in physical chemistry and physics from the University of Strasbourg (University Louis Pasteur, 2005). After his PhD work, Marc won the prestigious Fulbright fellowship in 2005 allowing him to work as visiting researcher at the University of Michigan in the group of Prof. Nick Kotov (Department of Chemical Engineering, Ann Arbor, USA). Between 2007-2008 he worked as researcher at the Technical University of Darmstadt in Germany (Department of Renewable Energies). Since 2008, Dr Michel works as senior scientist in the Materials Research and Technology Department of Advanced in The Luxembourg Institute of Science and Technology (LIST).

Dr. Michel’s research is focused on nanotechnologies, surface science, physical chemistry and in particular on the design of new architectures for renewable energies (EnergyCell Project funded by the Fond National de la Recherche Luxembourg). Dr. Michel has published more than 35 papers in his field of research.

About The Author

Joffrey Didierjean received his master’s degree in materials science from the École Européenne d’Ingénieurs en Génie des Matériaux (Nancy – France) in 2008. He firstly worked as an expert in surface and interface science at the Centre de Recherche Public Gabriel Lippmann in Luxembourg, where he was in charge of studies and analytical methods development on advanced characterization techniques. Since 2015, Joffrey Didierjean has been working in Dr. Michel’s team as research and technology engineer in the Material Science and Technology Department at the Luxembourg Institute of Science and Technology (LIST).

His field of competence covers surface science, nanomaterials and nanotechnologies and supramolecular assembly for the design of controlled architecture in the frame of renewable energy.

About The Author

Hongtao Long completed his Bachelor’s studies at University of Sciences and technologies of Taiyuan (China) in 2010, then he graduated from University of Lorraine (France) in 2013, and he is doing his Ph.D now at the Luxembourg Institute of Science and Technology (List), He started research on “Design of new generation of high performance electrodes for polymer exchange membrane fuel cells made of polyelectrolytes and nanoparticles complexes” with Professor Marc Michel in 2014.

He is interested in carbon materials, conducting polymer and their energy applications. He published “Polydopamine as a promising candidate for the design of high performance and corrosion-tolerant polymer electrolyte fuel cell electrodes” on Journal of power source in 2015.

About The Author

Doriane Del Frari joined the LIST (ex-CRP Henri Tudor) in 2007. From 2002 to 2005, she prepared her PhD in chemistry in the Laboratoire d’Electrochimie des Matériaux (Metz, France). Her PhD deals with the realization of thermoelectric materials by electrodeposition, for applications related to their properties, which lie mainly in the field of the heat transfer.

From 2006 to 2007, she worked at the Commissariat à l’Energie Atomique (Saclay, France) on an in situ AFM study of localized corrosion of stainless steel. Since 2007, she was in charge of the corrosion characterization of aluzinc samples (TRASU project) and electrochemical characterization domain of the materials unit.

She is currently in charge of electrical and electrochemical characterization at the Central Lab of the MRT department (Luxembourg Institut of Science and Technology).

 

Journal Reference

Hongtao Long³, Doriane Del Frari³, Arnaud Martin³, Joffrey Didierjean³, Vincent Ball^1,2, Marc Michel³, Hicham Ibn El Ahrach³. Polydopamine as a promising candidate for the design of high performance and corrosion-tolerant polymer electrolyte fuel cell electrodes. Journal of Power Sources, pp. 569-577, 2016.

Show Affiliations

¹ Unité INSERM 1121, Faculté de médecine, 11 rue Humann, 67085 Strasbourg Cedex, France

² Université de Strasbourg, Faculté de Chirurgie Dentaire, 8 rue Sainte Elisabeth, 67000 Strasbourg, France

³ Luxembourg Institute of Science and Technology (LIST), Materials and Research Technology (MRT), 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg

 

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Renewable Energy Global Innovations features: Sobol’s sensitivity analysis for a fuel cell stack assembly model with the aid of structure-selection techniques

Significance Statement

    This work presents a novel method for identifying the main parameters affecting the stress distribution of the components used in assembly modeling of proton exchange membrane fuel cell (PEMFC) stack. This method is a combination of an approximation model and Sobol’s method, which allows a fast global sensitivity analysis for a set of uncertain parameters using only a limited number of calculations.

Seven major parameters, i.e., Young’s modulus of the end plate and the membrane electrode assembly (MEA), the contact stiffness between the MEA and bipolar plate (BPP), the X and Y positions of the bolts, the pressure of each bolt, and the thickness of the end plate, are investigated regarding their effect on four metrics, i.e., the maximum stresses of the MEA, BPP, and end plate, and the stress distribution percentage of the MEA.

The proposed method was demonstrated to be feasible and effective at determining the most influential model parameters. Moreover, it enhances our understanding of the assembly of a PEMFC stack, and provides a valuable tool for a sensitivity analysis of a PEMFC stack assembly model.

The analysis reveals the individual effects of each parameter and its interactions with other parameters on the model performance regarding four metrics. The main findings from the results obtained are summarized as follows:

(1) The position of each bolt has a significant influence on the maximum stresses of the BPP and end plate, whereas the thickness of the end plate has the most crucial role in the maximum stress and stress distribution percentage of the MEA.

(2) The contact stiffness between the MEA and BPP has little effect on the maximum stresses of the BPP and end plate, and on the stress distribution percentage of the MEA. Moreover, it is not the most important factor affecting the maximum stress of the MEA when measured using a total-order sensitivity index. However, the contact stiffness interacting with the thickness of the end plate has a highly sensitive interaction effect on the maximum stress of the MEA.

(3) The parameter interactions contribute to a significant portion of the variation in the metric considering the maximum stress of the BPP. The interaction effects include the following: the thickness of the end plate interacts with its material property as well as the Y position of each bolt, the X position of each bolt interacts with its Y position, and the Y position of each bolt interacts with the pressure. 

About The Author

Dr. Wei Zhang received his B.Eng. in Engineering Mechanics from Hunan University, China in 2005, his M.Eng. and Ph.D. in Mechanical Engineering also from Hunan University, China in 2010 and 2013, respectively. He was an assistant engineer at Special Aircraft Research Institute of China from Aug. 2005 to Jun. 2007, and was a Post-Doctoral fellow at Department of Mechanical Engineering, Inha University, Korea from Nov. 2013 to Nov. 2015.

His research interests are in computational inverse techniques, uncertainty management and bioinspired design in composites. He is currently a research fellow at School of Mechanical & Aerospace Engineering, Queen’s University Belfast, UK. 

About The Author

Prof. Chongdu Cho received his B.Eng. in Mechanical Engineering from Seoul National University, Korea in 1983, his M.Eng. in Mechanical Engineering from KAIST, Korea in 1985 and his Ph.D. in Mechanical Engineering from University of Michigan, USA in 1991. He has been a visiting scholar in UCLA, USA from Jul. 2000 to Jul. 2001, and in Cornell University, USA from Aug. 2009 to Aug. 2010, respectively.

He has been developing FEA applications for various engineering products. He has published more than 150 referenced journal papers. Now, he is a fellow professor at Department of Mechanical Engineering, Inha University, Korea. 

Journal Reference

Journal of Power Sources, Volume 301, 2016, Pages 1–10.

Wei Zhang¹, Chongdu Cho¹, Changhao Piao¹, Hojoon Choi²

Show Affiliations

1. Department of Mechanical Engineering, Inha University, Incheon 402-751, South Korea
2. Korea Institute of Industrial Technology, Incheon 406-840, South Korea

Abstract

This paper presents a novel method for identifying the main parameters affecting the stress distribution of the components used in assembly modeling of proton exchange membrane fuel cell (PEMFC) stack. This method is a combination of an approximation model and Sobol’s method, which allows a fast global sensitivity analysis for a set of uncertain parameters using only a limited number of calculations. Seven major parameters, i.e., Young’s modulus of the end plate and the membrane electrode assembly (MEA), the contact stiffness between the MEA and bipolar plate (BPP), the X and Y positions of the bolts, the pressure of each bolt, and the thickness of the end plate, are investigated regarding their effect on four metrics, i.e., the maximum stresses of the MEA, BPP, and end plate, and the stress distribution percentage of the MEA. The analysis reveals the individual effects of each parameter and its interactions with the other parameters. The results show that the X position of a bolt has a major influence on the maximum stresses of the BPP and end plate, whereas the thickness of the end plate has the strongest effect on both the maximum stress and the stress distribution percentage of the MEA.

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Renewable Energy Global Innovations features: Catalytic fuel cell used as an analytical tool for methanol and ethanol determination. Application to ethanol determination in alcoholic beverages

Significance Statement

DMFC device used as an analytical tool for ethanol and methanol determination: applications to the analysis of real matrices.

Recently our research group has performed an experimental research [1,2], devoted to the utilization of Direct Methanol Fuel Cell (DMFC) as an analytical device, for methanol, or ethanol determination in real samples. After optimizing the best, among possible measurement formats, i.e. the open circuit, kinetic and potentiostatic format (the latter has been demonstrated the better) and discussing the effects of cross-over and temperature, it has been showed as a small commercial DMFC fuel cell can be useful to determine ethanol in alcoholic beverages, i.e. several wine and beer commercial samples. The obtained results have been compared both with ethanol content declared by the producer firm and with data obtained analyzing the same samples using a commercial amperometric catalase enzyme sensor [3]. The obtained correlation was found satisfactory and the precision, or lifetime of two methods comparable, only the measurement time was longer using the fuel cell. Nevertheless the possibility of improving the features, from the analytical point of view, of the catalytic fuel cell for methanol and ethanol, by introducing an enzyme (alcohol dehydrogenase), immobilized into a dialysis membrane small bag, in the anodic area of the fuel cell, has been recently demonstrated [4]. Using the enzymatic DMFC device, we have reached the goal concerning the drastic reduction of the measurement time by the fuel cell used for analytical purposes, enhancing at the same time its sensitivity [4]. Lastly the determination of other organic molecules, which contain an alcoholic function (although with a much lower sensitivity than methanol or ethanol) in real matrices, which do not contain high concentrations of possible alcoholic interfering compounds, was also demonstrated [4].

References

[1] M.Tomassetti, R.Angeloni, G. Merola, M. Castrucci, L.Campanella. Catalytic fuel cell used as an analytical tool for methanol and ethanol determination. Application to ethanol determination in alcoholic beverages. Electrochimica Acta, 191 (2016) 1001–1009.

[2] M. Tomassetti, R. Angeloni, G. Merola, M. Castrucci, L. Campanella. Catalytic Fuel Cell as an Analytical Tool for Methanol and Ethanol Determination. Proceedding of  2015 XVIII AISEM Annual Conference. 978-1-4799-8591-3/15/$31.00 ©2015 IEEE.

[3] R. Angeloni, M. Tomassetti, M. Castrucci, L. Campanella. Ethanol Determination in Alcoholic Beverages Using Two Different Amperometric Enzyme Sensors. Current Analytical Chemistry, 11 (2015) 56-67.

[4] M. Tomassetti, G. Merola, R. Angeloni, S. Marchiandi, L. Campanella. Further development on DMFC device used for analytical purpose. “manuscript in preparation”.

      

 

Figure Legend: DMFC H-TEC Model F111 Fuel Cell, obtained from Fuel Cell Store (College Station, TX, USA).

 

About The Author

Prof. Mauro Tomassetti, bachelor  in Chemistry (1969) and in Pharmacy (1977).  Full Professor of Analytical Chemistry at the University of Rome ‘La Sapienza’ since 2003; already Associate Professor since 1985 to the same University.

His research interests are in the development of electrochemical sensors, biosensors and immunosensors working both in aqueous and organic solvents and in their application to environmental, biopharmaceutical and food analysis.

He has also interest in thermal analytical studies (TG, DTA, DSC) for the purity control, or the characterisation of several materials (drugs, foodstuffs, polymers, etc.) and in the study and characterisation of archaeological finds and cultural heritages, investigated by means of several instrumental techniques of chemical analysis.

Member of teaching staff of  PhD in Engineering and Process.

Member of “Centro di ricerche applicate alla Protezione dell’Ambiente e dei Beni Culturali (CIABC)“, Sapienza University.

Member of “Istituto per lo Studio dei Materiali Nanostrutturati (ISMN)” of CNR .

Associate Editor of Current Analytical Chemistry.

Member of Editorial Board of Current Pharmaceutical Analysis.

Author of about 506 papers, 243 of which original research paper published on international Journals, and of about 460 communications to congress, overall in the above recorded fields of  research. 

Journal Reference

Electrochimica Acta, Volume 191, 10 February 2016, Pages 1001–1009.

Mauro Tomassetti*, Riccardo Angeloni, Giovanni Merola, Sergio Marchiandi, Mauro Castrucci, Luigi Campanella.

Department of Chemistry, University of Rome “La Sapienza”, p.le Aldo Moro, 5, 00185, Rome, Italy.

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