Article
Thermodynamics
Wei Gao, Qifeng Li, Kai Sun, Rui Chen, Zhizhao Che, Tianyou Wang
Summary: A new flow field structure was studied to improve the performance of fuel cells, which enhances oxygen transport and water removal capabilities for better cell performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Multidisciplinary
Huo Sen, Shi WeiYu, Wang RenFang, Lu BingBing, Wang Yang, Jiao Kui, Hou ZhongJun
Summary: Metal foam material as an alternative flow distributor in proton exchange membrane (PEM) fuel cell has attracted attention for its superior performance in providing uniform gas flow and accelerating water removal capability. Compared to traditional parallel flow channels, the operation of PEM fuel cell with metal foam distributor is less sensitive to cathode humidification and oxygen supply. The more uniform and effective electron transport in metal foam PEM fuel cell allows for the use of thinner gas diffusion layers.
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2021)
Article
Engineering, Chemical
Xingxiao Tao, Kai Sun, Rui Chen, Mengshan Suo, Huaiyu Liu, Zhizhao Che, Tianyou Wang
Summary: This study investigates the gas-liquid two-phase flow in the porous metal foam (PMF) flow field and identifies different flow patterns. Film, plug, and ligament flows are found in the hydrophilic PMF flow field, while slug and droplet flows are found in the hydrophobic PMF flow field. Optimizing pore size, increasing metal foam surface hydrophobicity, and optimizing operating conditions can improve water management in the PMF flow field.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Chemistry, Physical
Gangisetty Venkatesh, Rajappa Gnanamoorthy, Masakazu Okazaki
Summary: Slippage caused by vehicular and flow-induced vibrations can lead to fretting and contamination between the open-cell metal foam flow fields and other parts in a fuel cell, which may affect the performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Thermodynamics
Feng Sun, Dandan Su, Xuliang Nie, Yujie Yin, Shuaichang Qin, Xiaoping Dong
Summary: Metal foams with high porosity and electrical conductivity can greatly improve the performance of proton exchange membrane fuel cells (PEMFCs) by enhancing reactant transfer and accelerating the electrochemical reaction process. Increasing the porosity and pore density of the metal foam cathode flow field can significantly improve the current density and peak power of the PEMFC.
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2023)
Article
Chemistry, Physical
Yinghui Zhang, Youkun Tao, Hong Ren, Minhua Wu, Guanguang Li, Zhijian Wan, Jing Shao
Summary: This study demonstrates a simple and compact design for effective electrons and gas transport in proton exchange membrane fuel cells (PEMFCs) by using a porous metal foam flow media coated with a microporous layer. The design eliminates the conventional gas diffusion layer (GDL) and improves the performance of fuel cells.
JOURNAL OF POWER SOURCES
(2022)
Article
Chemistry, Physical
Chunhua Min, Fei Li, Xiaomeng Gao, Kun Wang, Zhonghao Rao
Summary: A numerical model of a PEMFC with serpentine flow field was set up in this study. Rectangular or triangular blocks were arranged in the cathode channel to improve cell performance. The results showed that the arranged blocks effectively enhanced reactant mass transfer and the triangular blocks performed better than the rectangular blocks. The blocks arranged in the rear of the turn exhibited the best cell performance, which was attributed to the combined effect of under-rib flow and secondary flow generated by the blocks.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Shoulei Miao, Zhenrong Liu, Haiqiu Zhang
Summary: 1,2,4-triazole is successfully grafted onto graphene oxide nanosheets by CC bonds without damaging other groups, resulting in improved oxidative stability and higher proton conductivity under anhydrous conditions. The PBI/NGO composite membranes exhibit superior mechanical properties and achieve a maximum proton conductivity of 27 mS cm(-1) for PBI/NGO-3 membrane at 160 degrees C, with a maximum power density of 254 mW cm(-2).
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Thermodynamics
Ying Huang, Jiangnan Song, Xinyue Deng, Su Chen, Xiang Zhang, Zongpeng Ma, Lunjun Chen, Yanli Wu
Summary: Flow channels with baffles can enhance reactant transport and improve the performance of PEMFC. This study compared the mass transfer and cell performance of PEMFC with different baffled channels using CFD method. The results showed that PEMFC with a cutting cylindrical baffle had the best performance, with an output current density of 1.82 A/m² at 0.4V voltage. Baffle design promoted reaction gas transmission and increased gas concentration in the channel. The presence of baffles improved mass transfer and water removal, but vortex generation led to parasitic power and decreased PEMFC performance.
Article
Environmental Sciences
Asif Jamil, Sikander Rafiq, Tanveer Iqbal, Hafiza Aroosa Aslam Khan, Haris Mahmood Khan, Babar Azeem, M. Z. Mustafa, Abdulkader S. Hanbazazah
Summary: Fuel cells are environmentally friendly technology with high efficiency and economic advantages. Proton exchange membranes, especially for hydrogen fuel cells, have great potential but face challenges in terms of cost and degradation of proton exchange capacity over time.
Article
Thermodynamics
Shipei Deng, Yinshi Li
Summary: A region-specific porous flow field (rs-PFF) is proposed to enhance the performance of proton exchange membrane fuel cells (PEMFCs) by improving heat, mass and charge transports. Experimental results show that the rs-PFF design can increase oxygen concentration, decrease temperature and improve peak power density, while saving energy consumption.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Chemistry, Multidisciplinary
Abhishek Kumar Arya, R. K. Singh Raman, Rahul Parmar, Matteo Amati, Luca Gregoratti, Sumit Saxena
Summary: Graphene coating shows remarkable corrosion resistance and high conductivity, making it an attractive option for bipolar plates in PEMFC.
Article
Energy & Fuels
Yimeng Peng, Xiaohui Yan, Chen Lin, Shuiyun Shen, Jiewei Yin, Junliang Zhang
Summary: Research shows that Toyota's 3D mesh flow field can significantly enhance oxygen supply and liquid water removal, but surprisingly, it results in the worst temperature uniformity and the highest maximum temperature difference, posing a challenge to the stack reliability.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Thermodynamics
Zihao Liao, Lin Wei, Ahmed Mohmed Dafalla, Zhenbang Suo, Fangming Jiang
Summary: Cold starting a PEMFC engine in sub-freezing temperatures presents technical challenges, with intra-electrode ice formation being a major concern. A study on PEMFCs with zigzag-channeled flow field (ZZFF) found that ZZFF enhances reactant/product distribution and current density, improving survivability but slightly degrading quick self-startup ability. Further research validates the effects of ZZFF configuration on PEMFC cold start performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Energy & Fuels
Xi Chen, Yao Chen, Qian Liu, Jianghai Xu, Qinxiao Liu, Wenbin Li, Yan Zhang, Zhongmin Wan, Xiaodong Wang
Summary: A stepped flow field of PEMFC bipolar plate is proposed to address the issues of non-uniform gas concentration distribution and flooding in the traditional parallel flow field. Computational fluid dynamics simulations show that fuel cells with stepped flow fields outperform traditional parallel flow field fuel cells by increasing net power by 21.5%, improving gas concentration and current density distribution uniformity, accelerating liquid water discharge, and alleviating water flooding phenomenon.
Review
Chemistry, Multidisciplinary
Segeun Jang, Yun Sik Kang, Dohoon Kim, Subin Park, Changwook Seol, Sungchul Lee, Sang Moon Kim, Sung Jong Yoo
Summary: This review summarizes the recent progress in the key components of polymer electrolyte membrane fuel cells (PEMFCs) based on a novel architecture strategy. Different architectural methods for patterning the membrane surface and electrode structures with diverse multiscale structures are discussed, as well as recent advances in the architectured transport layer for improving mass transportation.
ADVANCED MATERIALS
(2023)
Article
Engineering, Environmental
Jooyoung Kim, Hyunki Kim, Sungjun Kim, Jue-Hyuk Jang, Hyuntae Sohn, Seok Jin Hong, Junhyeong Kim, Gyeong Ho Han, Seonghyun Choe, Yung-Eun Sung, Soo Young Kim, Ho Won Jang, Tae Hwan Jo, Hyung-Kyu Lim, Sung Jong Yoo, Sang Hyun Ahn
Summary: This study presents a simple electrochemical strategy to fabricate atomic Pt clusters on Au dendrites, resulting in a significantly reduced Pt loading. The prepared Pt/Au/CP sample exhibits high selectivity for formic acid oxidation reaction and maintains stable activity even after cycling tests.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Myeong-Geun Kim, Seung-Hoon Kim, Jue-Hyuk Jang, Dong Wook Lee, Daeil Choi, Jae-Hyun Park, Kug-Seung Lee, Nanjun Chen, Chuan Hu, Young Moo Lee, Sung Jong Yoo
Summary: A nanotubular 1T Ru dichalcogenide with 92% of 1T phase was successfully synthesized, exhibiting high stability and electrocatalytic activity. This study provides a strategy for stabilizing metastable phases and stimulates interest in applying 1T phases and tubular structures for stabilizing metastable materials.
ADVANCED ENERGY MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Mansu Kim, Seung-hoon Kim, Jonghwan Park, Seongsoo Lee, Injoon Jang, Sohui Kim, Chang Yeon Lee, Oh Joong Kwon, Hyung Chul Ham, Joseph T. T. Hupp, Namgee Jung, Sung Jong Yoo, Dongmok Whang
Summary: Downsizing a catalyst nanoparticle to a single atom has been successful in increasing its catalytic activity and reducing the amount of catalyst needed for electrochemical reactions. However, the stability of single-atom site catalysts remains a challenge. This study proposes using stable metal oxide nanoparticles as supports to enhance the electrochemical activity and stability of single-atom catalysts for the hydrogen evolution reaction.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Jae Young Jung, Haneul Jin, Min Woo Kim, Sungjun Kim, Jeong-Gil Kim, Pil Kim, Yung-Eun Sung, Sung Jong Yoo, Nam Dong Kim
Summary: This study demonstrates the occurrence of atom-migration-trapping (AMT) phenomena in crystalline porous nanocarbon and develops highly efficient single-atom catalysts (SACs) through systematic investigation of atomization process and chemical state of active sites. The pre-formed N-functionalities in the catalyst play a crucial role in capturing single metal species, and additional ammonia treatment successfully modulates the coordination geometry of active sites. The atomic cobalt catalyst exhibits superior oxygen reduction activity and remarkable power performance in single-cell experiments, surpassing reported Co-N atomic catalysts.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Energy & Fuels
Dong-gun Kim, Injoon Jang, Yeonsun Sohn, Eunhye Joo, Chanil Jung, Nam Dong Kim, Jae Young Jung, Vinod K. Paidi, Kug-Seung Lee, Pil Kim, Sung Jong Yoo
Summary: In this study, we investigated the significance of posttreatment in the design of Fe-N-C catalysts for ORR. By removing the aggregated iron species and optimizing the annealing temperature, we were able to enhance the catalytic performance and durability of the catalyst. The type of acid used for removing the iron species also influenced the Fe and nitrogen contents, further affecting the ORR performance of the catalyst.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Sahng Hyuck Woo, Nak Jun Lee, Seung Ho Yook, Hee Soo Kim, Jieun Choi, Jae-Hun Kim, So Young Lee, Jong Hyun Jang, Sung Jong Yoo, Young-Gi Yoon, Jonghee Han, Hyoung-Juhn Kim
Summary: This research used an imaging technique to find new reasons for the reduced performance of polymer electrolyte fuel cells (PEFCs). H+ and OH- indicator sensors were attached to each electrode of a membrane electrode assembly and quantitative analysis of ion generation was conducted using digital microscopes. The proposed reactions in the fuel cell were confirmed and various reactions occurring in the electrode were examined.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Seung Yeop Yi, Eunho Choi, Ho Yeon Jang, Seonggyu Lee, Jinkyu Park, Daeeun Choi, Yeju Jang, Hojin Kang, Seoin Back, Segeun Jang, Jinwoo Lee
Summary: By tuning the local environment of atomically dispersed iron catalysts through defect engineering, improved performance in proton exchange membrane fuel cells can be achieved. The optimized catalyst exhibits excellent oxygen reduction reaction activity and shows great potential for practical applications.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Yongkeun Kwon, Doosun Hong, Jue-Hyuk Jang, Minjoong Kim, Sekwon Oh, Donghoon Song, Jeonghoon Lim, Sung Jong Yoo, Eunae Cho
Summary: In the development of anion exchange membrane fuel cells (AEMFCs), the sluggish hydrogen oxidation reaction is a major challenge. The study suggests that the Ni-29Mo composite catalyst shows superior activity in the HOR, outperforming platinum catalysts and demonstrating practical applicability in AEMFCs.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Hui-Yun Jeong, Jinho Oh, Gyu Seong Yi, Hee-Young Park, Sung Ki Cho, Jong Hyun Jang, Sung Jong Yoo, Hyun S. Park
Summary: A highly active water-oxidizing anode based on a core-shell catalyst structure was developed to reduce the usage of rare-earth metals in a proton-exchange-membrane water electrolyzer (PEMWE). The core-shell nanostructure showed low resistances and enhanced transfer of protons, water, and oxygen on the catalyst layer. The stability of the catalysts was achieved by passivating the surfaces of transition-metal nitrides (TMNs) with chemically stable Ir catalyst layers.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Review
Chemistry, Multidisciplinary
Subin Park, Daeil Choi, Dong Wook Lee, Baeck B. B. Choi, Sung Jong Yoo
Summary: The transition to renewable energy has led to the development of fuel cells using hydrogen as fuel, but commercialization remains slow due to the high cost of platinum catalysts. An alternative option is anion exchange membrane fuel cells that use non-precious metal catalysts, which have shown promise in achieving comparable performance to platinum. Efficient catalyst development, along with electrode structure design, can help overcome the cost barrier and make these fuel cells more feasible.
KOREAN JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Yujin Park, Joondong Kim, Ju-Hyung Yun, Segeun Jang, Sang Moon Kim
Summary: The pressure-driven liquid flow controller is a crucial component in various applications. The conventional safety valves have limitations, while electric feedback loop based flow controllers are expensive and complex. This study proposes a simple and controllable liquid-flowing system using an oil-gated isoporous membrane (OGIM) as a responsive and precise gas valve, enabling constant liquid flow.
Article
Chemistry, Multidisciplinary
Myeong-Geun Kim, Tae Kyung Lee, Eungjun Lee, Subin Park, Hyun Ju Lee, Haneul Jin, Dong Wook Lee, Min-Gi Jeong, Hun-Gi Jung, Kyungmin Im, Chuan Hu, Hyung Chul Ham, Kwang Ho Song, Yung-Eun Sung, Young Moo Lee, Sung Jong Yoo
Summary: In this study, an efficient electrode structure was developed using a corrosion-resistant hydrophobic crystalline carbon support as a carrier for Fe-Ni-Co layered double hydroxide electrocatalysts. The results showed a higher activity and durability than previous studies in anion exchange membrane water electrolysis. This improvement can be attributed to the rapid water diffusion and strong metal-carbon interactions. This study is expected to promote the development of more carbon-supported oxygen evolution reaction electrocatalysts.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Chuan Hu, Na Yoon Kang, Hyun Woo Kang, Ju Yeon Lee, Xiaohua Zhang, Yong Jun Lee, Seung Won Jung, Jong Hyeong Park, Myeong-Geun Kim, Sung Jong Yoo, So Young Lee, Chi Hoon Park, Young Moo Lee
Summary: Researchers have developed a new type of polymer electrolyte for alkaline energy conversion devices using highly rigid triptycene as a branching agent. The electrolyte exhibits excellent conductivity, mechanical properties, anti-swelling ability, and alkaline stability. Fuel cells and water electrolyzers based on this electrolyte demonstrate promising performance, indicating wide application potential.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Chuan Hu, Hyun Woo Kang, Seung Won Jung, Mei-Ling Liu, Young Jun Lee, Jong Hyeong Park, Na Yoon Kang, Myeong-Geun Kim, Sung Jong Yoo, Chi Hoon Park, Young Moo Lee
Summary: This study presents a rational design of high-performance anion exchange polyelectrolytes (AEPs) for energy conversion devices. Incorporating highly-rigid twisted spirobisindane monomer in the polymer backbone, the AEPs exhibit continuous ionic channels, dimensional stability, and excellent electrochemical performances. The AEPs achieve new current density records and outstanding durability in anion exchange membrane water electrolyzers (AEMWEs), and also demonstrate high power density in fuel cells.