Article
Engineering, Chemical
Henghui Huang, Shaoyi Xu, Jiexin Zhou, Feiyan Luo, Jiantao Fan, Hui Li
Summary: The chemical stability of a proton exchange membrane (PEM) can be improved by introducing hindered amine functionalized carbon quantum dots (HA-CQDs) which effectively eliminate active free radicals. The free radical scavenging capability of HA-CQDs was evaluated using the DPPH radical method, and it was found that introducing hindered amines can eliminate free radicals generated by electrochemical reactions and mitigate chemical degradation of the PEM. This research provides a promising approach to enhance the chemical stability of perfluorosulfonic acid (PFSA) and increase the lifetime of PEMs.
JOURNAL OF MEMBRANE SCIENCE
(2021)
Article
Chemistry, Physical
Xingying Bai, Qifei Jian, Bi Huang, Lizhong Luo, Yangyang Chen
Summary: The introduction of a dual-path hydrogen supply strategy improves hydrogen diffusion within the fuel cell stack, while optimized start-up loading strategies enhance stack voltage and single-cell temperature uniformity.
JOURNAL OF POWER SOURCES
(2022)
Article
Polymer Science
Yujiao Li, Shicheng Xu, Jin Wang, Xiaoxiao Liu, Yunfei Yang, Fan Yang, Ronghuan He
Summary: The novel poly(terphenyl pyridine) polymers synthesized through an acid-catalyzed polycondensation reaction exhibit high proton conductivity when doped with phosphoric acid. The membranes show good performance and stability in various tests.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Materials Science, Composites
Yao Wang, Yanming Wang, Yizheng Wang, Bihai Su, Linlin Shi, Feibo Li, Jingbo Mu, Hongwei Che, Zhixiao Zhang, Xiaoliang Zhang, Ping Li, Feng Li
Summary: This study prepared ionic liquid grafted boron nitride (ILs@BN) using wet ball milling, and fabricated polyimide (PI) composite films with different contents (1, 2, 3, 4, and 5 wt%) of ILs@BN by solution-casting method. The obtained composite films showed significantly improved performance compared to the original polyimide films. The film containing 4 wt% ILs@BN exhibited enhanced tensile strength, better hydrophilicity, and excellent proton conductivity, showing great potential applications in fuel cells.
POLYMER COMPOSITES
(2023)
Review
Engineering, Chemical
Ying Shi Chang, Priyanka Kumari, Catherine J. Munro, Gyorgy Szekely, Lourdes F. Vega, Suzana Nunes, Ludovic F. Dumee
Summary: Plasticization is a common problem in polymeric membranes, where specific compounds can cause the material to degrade and lose performance. However, through smart material design and engineering processes, such as crosslinking and blending, this plasticization effect can be minimized. This review critically presents recent approaches to tackle plasticization in glassy polymeric membranes and offers recommendations for future work.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Daijun Yang, Yongle Tan, Bing Li, Pingwen Ming, Qiangfeng Xiao, Cunman Zhang
Summary: This review focuses on the structure and degradation problems of the transition region in the membrane electrode assembly (MEA) of a proton exchange fuel cell (PEMFC). It emphasizes the importance of reliable design and structure to avoid early failure. Integration of materials in the transition region is identified as a development trend. Mitigation approaches and durability testing methods are also discussed.
Article
Polymer Science
Muhammad Habib Ur Rehman, Ernestino Lufrano, Cataldo Simari
Summary: This study investigated the effect of introducing layered double hydroxide (LDH) into different polymer matrices. The LDHs can provide additional hydrophilic sites or act as physical crosslinkers, leading to enhanced dimensional stability and electrochemical performance. The relevant filler choice is crucial for the preparation of highly-performing composites.
Article
Agricultural Engineering
Ali Zarei-Baygi, Adam L. Smith
Summary: While iARGs are predominant in nutrient-rich environments, eARGs are more prevalent in aquatic environments. eARGs can be adsorbed by soil and sediment particles, protected from degradation, and therefore persist longer than iARGs. The characteristics of eARGs emphasize their crucial role in the spread of antibiotic resistance in the environment.
BIORESOURCE TECHNOLOGY
(2021)
Article
Chemistry, Physical
Shaojie Ke, Chaoyong Sun, Bolan Cui, Yufeng Qi, Meiling Dou
Summary: The anode of hydrogen fuel cell electric vehicles (FCEVs) is often contaminated with impurities like CO, H2S, and NH3, which greatly reduce the durability of proton exchange membrane fuel cells (PEMFCs). This study proposes two strategies, temporary temperature increase during hydrogen purging and internal oxygen permeation, to mitigate H2S poisoning in the anode and improve PEMFC durability. The first strategy accelerates the desorption of H2S and releases more Pt reactive sites for hydrogen oxidation reaction (HOR) catalysis, while the second strategy oxidizes sulfur on the anode using oxygen permeated through a thin PEM. These strategies have the potential to enhance the long-term performance of PEMFCs and reduce the cost of hydrogen purification for FCEVs.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Engineering, Chemical
Hui Ding, Peng Sun, Yan Wang, Zihan Xia, Ping Li, Chengzhi Cui, Mingyu Li, Zhongfang Li
Summary: In this study, a flexible branched polymer, a cross-linkable water-soluble proton conductor, and a multi-functional cross-linker were designed to fabricate high-temperature proton exchange membranes with good comprehensive performances. The branched structure of the polymer and the cross-linker improved proton conductivity and mechanical properties, while the cross-linking process enhanced membrane strength and oxidative resistance. However, excessive cross-linking or branching can deteriorate membrane performances.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Review
Chemistry, Applied
Zunmin Guo, Maria Perez-Page, Jianuo Chen, Zhaoqi Ji, Stuart M. Holmes
Summary: Efforts to design and develop phosphoric acid-based proton exchange membrane for high-temperature fuel cells have been made globally. Various approaches, including crosslinking, introducing antioxidative groups, and incorporating inorganic materials, have been proposed to mitigate the degradation of the membranes. Crosslinking, blending with stable polymers and inorganic materials, and preparing polymers with high molecular weight are recommended to improve membrane mechanical strength. Three promising approaches to improve the durability of HT-PEMFCs include crosslinking, incorporating hygroscopic inorganic materials, and increasing membrane layers or introducing strong basic groups and electron-withdrawing groups.
JOURNAL OF ENERGY CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Xin Wei, Ru-Zhi Wang, Wei Zhao, Ge Chen, Mao-Rong Chai, Lei Zhang, Jiujun Zhang
Summary: This review highlights the main causes of PEMFC performance degradation and recent research progress on developing mitigation strategies. It emphasizes understanding catalyst poisoning phenomena, influencing factors, and general degradation mechanisms. Additionally, it analyzes technical challenges and proposes future research directions to facilitate the further development of mitigation strategies for PEMFC catalyst degradation.
Article
Chemistry, Physical
Fanghua Liu, Kenji Miyatake
Summary: In this study, a new series of sulfonated polyphenylene ionomers (SPP-TFP) were designed and synthesized as highly proton conductive and durable proton exchange membranes. These ionomers exhibited high solubility and flexibility, and showed excellent proton conductivity and durability for practical fuel cell applications.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Review
Green & Sustainable Science & Technology
Caizhi Zhang, Yuqi Zhang, Lei Wang, Xiaozhi Deng, Yang Liu, Jiujun Zhang
Summary: This paper reviews the state of health prediction and mitigation techniques for proton exchange membrane fuel cell (PEMFC) systems in electric vehicles, with a focus on analyzing failure mechanisms and proposing innovative solutions to extend the system's service life. The limitations of existing diagnostic techniques and mitigation solutions are discussed, and future research directions for commercializing PEMFC system-based electric vehicles are proposed.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Engineering, Chemical
I Salmeron-Sanchez, J. Asenjo-Pascual, J. R. Aviles-Moreno, J. C. Perez-Flores, P. Mauleon, P. Ocon
Summary: This study modified four commercially available ion exchange membranes to reduce the crossover phenomena of redox active species in AORFB systems. The modified membranes showed optimal properties with minimal impact on ion conductivity, making them appealing for AORFB applications. Additionally, the modified anionic exchange membranes demonstrated increased ion exchange capacity and greater double layer stability compared to cationic exchange membranes.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Energy & Fuels
Mengjun Wu, Yijing Xing, Liuli Zeng, Wei Guo, Mu Pan
Summary: A novel carbon support material (C-framework) for PEMFC was reported using salt-recrystallization-fixing HKUST-1 template. The C-framework loaded with Pt nanoparticles exhibited high ORR activity and excellent electrochemical performance in acidic electrolytes. The PEMFC performance reached a maximum power density of 780 mW/cm(2) under ultra-low Pt loading.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Energy & Fuels
Pinelopi Angelopoulou, Spyros Kassavetis, Joan Papavasiliou, Dimitris Karfaridis, Grzegorz Slowik, Panos Patsalas, George Avgouropoulos
Summary: This study successfully improved the electrochemical performance of LiAl0.1Mn1.9O4 cathode material by coating TiN layer, leading to remarkable long-term cycling stability by reducing the electrode/electrolyte interface contact area.
Article
Energy & Fuels
Lei Liu, Yizhe Li, Rui Qiao, Yijing Xing, Haibin Li
Summary: By depositing ZrO2 coating on polydopamine-modified ePTFE skeletons, the interfacial binding between the skeletons and PFSA ionomer is improved, and the migration of antioxidant additives is restrained, resulting in enhanced performance of composite membranes.
Article
Energy & Fuels
Konstantinos Kappis, Joan Papavasiliou, George Avgouropoulos
Summary: The production of hydrogen through methanol reforming processes, especially steam reforming, has attracted significant interest due to its ability to produce high concentrations of hydrogen with minimal carbon monoxide. Different catalytic systems, preparation methods, and integration with high temperature-polymer electrolyte membrane fuel cells are being actively studied in this field.
Editorial Material
Chemistry, Multidisciplinary
John Vakros, George Avgouropoulos
Article
Chemistry, Physical
Lei Liu, Yijing Xing, Yifan Li, Zhiyong Fu, Zhuoqun Li, Haibin Li
Summary: In this study, double layers of ePTFE reinforcement were intercalated into PFSA ionomer to improve the mechanical durability of PEMs. The double-layer ePTFE reinforcement significantly increased the mechanical strength and reduced the area swelling rate. Additionally, the double-layer ePTFE enhanced membranes showed better performance and durability under alternating wet/dry conditions compared to single-layer ePTFE reinforced membranes.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Christos Papadopoulos, Konstantinos Kappis, Joan Papavasiliou, John Vakros, Aspasia Antonelou, Wojciech Gac, Haibin Li, George Avgouropoulos
Summary: CuCe mixed oxides are commonly used for preferential CO oxidation in the purification of hydrogen-rich gas stream. This study investigated the synthesis of various ceria supports and the preparation of CuCe mixed-oxide catalysts. It found that modifying the hydrothermal parameters can tune the properties of the supports, leading to highly active and selective catalysts. The nature of the reduced copper species and the optimum content in oxygen vacancies play crucial roles in the catalytic performance.
Article
Chemistry, Physical
Lei Liu, Yijing Xing, Yifan Li, Zhiyong Fu, Zhuoqun Li, Haibin Li
Summary: This article presents a strategy to develop highly durable proton exchange membranes (PEMs) for proton exchange membrane fuel cells (PEMFCs) by intercalating double-layer expanded polytetrafluoroethylene (ePTFE) skeletons and doping CeO2 radical scavengers into perfluorosulfonic acid (PFSA) membranes. The results show that the developed membranes have significantly improved mechanical properties, lower swelling rates, and superior dimensional stability compared to conventional single-layer ePTFE reinforced membranes. They also exhibit better chemical durability behaviors and lower hydrogen crossover increase, reduced power performance attenuation, and smaller membrane impedance increase. The CeO2-doped membranes further enhance chemical durability during the open-circuit voltage durability test. Overall, the developed membranes are promising candidates for advanced PEMs with high mechanical and chemical durability for PEMFC applications.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Energy & Fuels
Yijing Xing, Lei Liu, Zhuoqun Li, Yifan Li, Zhiyong Fu, Haibin Li
Summary: The study introduced a reinforced MEA prepared using reinforcement embedding technology and direct membrane deposition approach, showing higher performance and mechanical durability, especially under low-humidity operating conditions.
Article
Chemistry, Physical
Yifan Li, Konstantinos Kappis, Joan Papavasiliou, Zhiyong Fu, Li Chen, Haibin Li, Dimitrios E. Vlachos, George Avgouropoulos
Summary: In this study, a fuel cell based on a molten proton conductor electrolyte membrane was developed, which can operate efficiently at high temperatures through integration with a CuZn-based methanol reformer. The experiment showed that the fuel cell could provide a voltage of 0.7 V and maintain a high open circuit voltage at 220℃.
JOURNAL OF POWER SOURCES
(2022)
Article
Energy & Fuels
Zhuoqun Li, Yijing Xing, Lei Liu, Yifan Li, Zhiyong Fu, Haibin Li
Summary: To improve the performance of proton-exchange membrane fuel cells (PEMFCs), optimizing the interfacial contact between the proton-exchange membrane (PEM) and the catalyst layer (CL) is necessary. A novel fabrication method for the membrane electrode assembly (MEA) of PEMFCs is proposed, where perfluorosulfonic acid (PFSA) dispersion is coated on a substrate to form a wet film, and a gas diffusion electrode (GDE) is placed on the wet PFSA film. This approach prevents excessive penetration of liquid PFSA dispersion into the CL and achieves excellent interfacial contact between the PEM and the CL.
Article
Engineering, Environmental
Konstantinos Kappis, Joan Papavasiliou, Marcin Kusmierz, Grzegorz Slowikc, Yifan Li, Haibin Li, Wojciech Gac, George Avgouropoulos
Summary: Steam reforming of methanol using CuZnOx catalysts was investigated, and the incorporation of Ga was found to improve catalyst performance by altering the environment and promoting the formation of ZnGa2O4 spinels and oxygen vacancies. The presence of Ga2O3 (15 wt%) was beneficial for activity and selectivity, and the formation of a CuZnGaAlOx system further enhanced the performance. The most active material showed promising results in an integrated internal reforming methanol fuel cell operating at 220 degrees C.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Lei Liu, Zhiyong Fu, Yijing Xing, Yifan Li, Zhuoqun Li, Haibin Li
Summary: The study presents a novel preparation method for membrane electrode assemblies (MEAs) by wet-combining interface forming strategy. The method fabricates high-performance MEAs with ultrathin proton exchange membranes (PEMs). The new MEAs show significantly higher electrochemical surface area and superior power performance compared to conventional MEAs prepared by catalyst-coated membrane method. The MEAs also possess a hydrogen crossover current similar to commercial membranes, demonstrating excellent mechanical durability.
