ACS Sustainable Chemistry & Engineering
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2022
·
IF 9.224
Tianyi Gu,Qian Zhang,Ruhua Shi,Jin Yan,Jie Guo,Wei Qian,Bowen Zhai,Mingzheng Zhou,Maorong Chai,Ruizhi Yang
Microporous layer (MPL) is a vital component for proton-exchange membrane fuel cells (PEMFCs) to improve the cell performance. However, the conventional preparation of MPL, involving the mixing of carbon black with hydrophobic agent polytetrafluoroethylene (PTFE), followed by high-temperature annealing, is often complicated and costly. Herein, we present a facile and low-cost method to fabricate the MPL by functionalization of carbon black via covalent bonding with hydrophobic agent. Upon chemical grafting with fluoroalkylsilane (FAS-17), the water contact angle of carbon black is increased from 66.4 to 150.4°, resulting in superhydrophobicity. The MPL prepared with the resultant superhydrophobic carbon endows the PEMFC with enhanced gas and water permeability and hereby improved electrochemical performance over traditional MPL, and a maximum power density of 1211 mW cm–2 for the PEMFC can be obtained. This work offers a feasible strategy to construct an efficient MPL for the PEMFC via a chemical grafting approach.
研究领域:
材料科学
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能源工程
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
·
IF 5.518
Zhekun Chen,Weitong Pan,Dingsong Yao,Ming Gao,Yunfei Gao,Xueli Chen,Jaroslaw Krzywanski,Fuchen Wang
Study on the film crack formation process of microporous layer (MPL) in fuel cells is necessary as the size of cracks substantially affects fuel cell durability. In-situ characterization of crack evolution in the full MPL ink drying process is essential to understand the crack formation mechanism. In this work, quasi in-situ crack evolution in the full MPL ink drying process under different stages is comprehensively investigated using ESEM, PLM , and regular SEM . A crack formation with subsequent crack healing mechanisms is discovered. Physiochemical characterizations indicated that the crack formation process is related to the evaporation of isopropanol, whereas the crack healing process is related to the subsequent evaporation of water. Experiments on solvent composition further indicate that the final crack size depends on the ink dispersion during the drying process. Furthermore, the optimal 1/2 IPA/water weight ratio formulation is proposed for the resulting MPL with fewer cracks.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Qian Zhang,Tianyi Gu,Ruhua Shi,Jin Yan,Wei Wang,Wei Qian,Bowen Zhai,Mingzheng Zhou,Maorong Chai,Ruizhi Yang
The hydrophobicity of microporous layer (MPL) plays an important role in the water management and thereby performance improvement of proton exchange membrane fuel cells (PEMFCs). Hydrophobic additive polytetrafluoroethylene (PTFE) used in the conventional MPL requires post-heat treatment at high temperature and tends to block the pores of MPL. Herein, we develop a facile and low-cost method to fabricate the MPL layer by functionalizing carbon with 3-(Trimethoxysilyl) propyl methacrylate (KH570). Covalently grafted KH570 endows carbon black with super-hydrophobicity and high stability. The contact angle of carbon black increases from 63° to 157° upon covalent cross-linking with KH570, resulting in super-hydrophobicity. The MPL fabricated with thus-functionalized carbon black is tested in a PEMFC, which delivers a maximum power density up to 1265 mW cm −2 , superior to that of PEMFC based on traditional MPL. This fluorine-free, covalent grafting protocol may open up a new avenue for the construction of MPL for PEMFC.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Xinyuan Wang,Gang-Ping Wu
The microporous layer (MPL) in membrane electrodes is critical for mass transfer in proton-exchange membrane fuel cells (PEMFCs). The mass transfer loss in electrodes is very serious when operating in high-current-density and high-humidity environments, which greatly reduces the output performance and durability of fuel cells. To address these challenges, we designed an MPL with a graded pore structure. By controlling the content of the pore former in the MPL slurry, conventional MPLs with uniform pores are constructed, and then structural MPL with ordered gradient pore distribution is formed through layered coating and sintering. The capillary driving force provided by such a gradient structure can effectively improve the cathode water management capability. In this study, the MPL with the graded pore structure (G-MPL) shows the highest output performance of 2.28 W cm–2 at a high relative humidity of 100%. This is mainly due to its gradient pore structure, which significantly facilitates water discharge and gas diffusion, thereby upgrading the mass transfer capacity of fuel cells. In addition to its outstanding electrochemical performance, G-MPL also has the advantages of low production cost and a simplified preparation process, making it an exceptional candidate to promote the practical application of PEMFCs.
研究领域:
能源科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2015
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IF 2.729
Jinkai Hao,Shuchun Yu,Yongyi Jiang,Xiaojin Li,Zhigang Shao,Baolian Yi
In this paper, antimony doped tin oxide (ATO) was firstly used as a conductive material in the microporous layer (MPL). ATO had higher electrochemical stability than XC-72 carbon powder. With the same thickness of MPL, the electrochemical corrosion behavior of gas diffusion layers (GDLs) prepared with ATO and XC-72 carbon powder in the simulated PEMFC operation environment were examined and the results showed that the GDL prepared with ATO had higher durability after oxidation for 55 h. Besides, the fuel cell performance with the GDLs prepared with ATO and XC-72 carbon powder as the cathode GDLs were evaluated and a very small difference between those two cells was observed at low current densities, which demonstrated that GDL prepared with ATO had wide application prospects.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2014
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IF 2.93
Shuchun Yu,Xiaojin Li,Jinkai Hao,Sa Liu,Zhigang Shao,Baolian Yi
A new method of preparing microporous layer (MPL) for proton exchange membrane fuel cell (PEMFC) was presented in this paper. Considering the bad dispersion of PTFE aqueous suspension in the carbon slurry based on ethanol, polyvinylpyrrolidone (PVP) aqueous solution was used to prepare carbon slurry for microporous layer. The prepared gas diffusion layers (GDLs) were characterized by scanning electron microscopy, contact angle system and pore size distribution analyzer. It was found that the GDL prepared with PVP aqueous solution had higher gas permeability , as well as more homogeneous hydrophobicity . Moreover, the prepared GDLs were used in the cathode of fuel cell and evaluated with fuel cell performance and EIS analysis, and the GDL prepared with PVP aqueous solution indicated better fuel cell performance and lower ohmic resistance and mass transfer resistance.
研究领域:
材料科学
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能源工程
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
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2021
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IF 8.001
Tianya Li,Kejian Wang,Jihao Wang,Yueqi Liu,Yufen Han,Zhiyang Xu,Guangyi Lin,Yong Liu
As a rising star, the fuel cell will be applied very broadly. However, when the fuel cell works at a high current, too much water yield and the redundancy water block the air or oxygen enter the fuel cell, then the power reduces sharply. The gas diffusion layer (GDL) in the fuel cell is the critical component to transfer water and gas. A novel GDL was prepared in this paper to improve transferability. The new GDL consists of one carbon paper and two microporous layers. The microporous layer close to carbon paper is modified by pore-former CaCO 3 . The total thickness of the new GDL is 270 μm; then, the samples were pressed to 220, 240, and 260 μm by rolling, respectively. The electrochemical impedance spectroscopy tests at a large current (2.5 A/cm 2 ) show that the fuel cell with 240 μm GDL has relatively small transmission impedance regardless of high or low humidity. The results show that the new GDL can significantly improve the water transferability of the proton exchange membrane fuel cell.
研究领域:
能源科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2024
·Vol. 17
·期 7
·6095-6101
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IF 9.5
Wang Shunzhong,Hu Kadi,Chen Wei,Cao Yali,Wang Linan,Wang Zhichang,Cui Lirui,Zhou Mingzheng,Zhu Wei,Li Hui,Zhuang Zhongbin
The ordered membrane electrode assembly (MEA) has gained much attention because of its potential in improving mass transfer. Here, a comprehensive study was conducted on the influence of the patterned microporous layer (MPL) on the proton exchange membrane fuel cell performances. When patterned MPL is employed, grooves are generated between the catalyst layer and the gas diffusion layer. It is found that the grooves do not increase the contact resistance, and it is beneficial for water retention. When the MEA works under low humidity scenarios, the MEA with patterned MPL illustrated higher performance, due to the reduced inner resistance caused by improved water retention, leading to increased ionic conductivity. However, when the humidity is higher than 80% or working under high current density, the generated water accumulated in the grooves and hindered the oxygen mass transport, leading to a reduced MEA performance.
研究领域:
电化学
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能源材料
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燃料电池技术
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界面工程
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传质过程
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2023
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IF 5.3
Qian Zhang,Tianyi Gu,Ruhua Shi,Xian Wei,Wei Wang,Jie Guo,Ruizhi Yang
The construction of a microporous layer (MPL) on carbon paper in proton exchange membrane fuel cells (PEMFCs) is crucial for water management during cell operation. Hydrophobic treatment of MPL is the key to cell performance improvement. However, the conventional MPL treated with polytetrafluoroethylene (PTFE) requires heat-treatment at high temperatures, and the pores can be easily blocked, which is not beneficial for the water drainage and gas transport. In this study, we introduce a straightforward technique for the chemical refinement of MPLs, utilizing hexadecyltrimethoxysilane (HDTMS) to impart functional properties to carbon materials. Benefiting from covalently grafting carbon with HDTMS, the MPL with superhydrophobicity and open pores/channels can be obtained. A high contact angle of 155° is achieved for MPL upon chemical grafting with HDTMS. The PEMFC, equipped with our custom-engineered MPL, achieves an outstanding maximum power density of 1307 mW cm–2, outperforming cells outfitted with traditional MPL configurations. It has been demonstrated that this chemical engineering protocol holds great promise in constructing an MPL for PEMFC.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2024
·
IF 8.1
Lianqin Wang,Jie Yao,Yabiao Pei,Weikang Zhu,Zhizhao Che,Junfeng Zhang,Yan Yin,Michael D. Guiver
Microporous layers play a crucial role as one of the main components of the membrane electrode assembly (MEA) in facilitating effective water management for proton exchange membrane fuel cells (PEMFCs), which is vital for maintaining optimal performance in a wide humidity range . Herein, Zn-based zeolitic imidazolate framework-8 (ZIF-8)-derived material (ZDM) as a porous carbon material is first developed to construct the microporous layer (MPL). With higher gas permeability , improved water management, and increased electrical conductivity , the MPL equipped with a ZDM layer, denoted as MPL-Z, exhibits superior performance, surpassing commercial MPLs throughout the range of 30–100% relative humidity (RH). The peak power density of an H 2 /air PEMFC at 70% RH utilizing a MPL-Z is 3.3 times that of commercial MPL. Furthermore, a unique patterned dual MPL is designed to boost the performance, ultimately achieving a peak power density of 1.50 W cm −2 (H 2 /air) with a low total Pt loading of 0.3 mg Pt cm −2 at 100 % RH. Even at only 30% RH, the peak power density can reach 0.72 W cm −2 (H 2 /air). The results demonstrate that the material and structural design of the MPL allows for the efficient operation of low Pt loading PEMFCs over a wide humidity range.
研究领域:
电化学
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能源材料
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纳米结构材料
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燃料电池技术
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界面工程
✓ 已验证
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Xin Zhang,Shuhan Cai,Daliang Guo,Hongtao Zhang,Lizheng Sha
The development of hydrophilic-modified gas diffusion layer (GDL) has become a prerequisite for enhancing the performance of proton exchange membrane fuel cells (PEMFCs) at various humidity conditions, especially at low humidity. In this paper, a novel hydrophilic-modified GDL was prepared by doping polyaniline@titanium dioxide (PANI@TiO 2 ) composite as a conductive component in MPL. This composite had been demonstrated to have a core–shell structure with advantageous properties such as enhanced conductivity, stability, and obvious hydrophilicity. The single cell tests demonstrated that the modified GDL presented better performance than conventional GDL at various relative humidities (RHs) conditions (40 ∼ 100 %), especially at low humidity. The incorporation of this composite resulted in the increased proportions of mesopores and micropores, reaching maximum values of 16.21 % and 0.51 %, respectively, at a content of 5 %. The maximum power density was increased by 54.52 % compared to the conventional GDL at 70 %RH. This enhancement was attributed to the powerful wettability and pore size distribution modification of PANI@TiO 2 composite. The findings indicated that the remarkable water retention ability of PANI@TiO 2 composite enhanced hydration processes, which offered a practical approach to develop hydrophilic-modified GDLs for PEMFCs applications.
研究领域:
电化学
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能源材料
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纳米复合材料
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燃料电池技术
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表面改性
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 8
·3561-3572
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IF 3.5
Guo Jie,Wang Wei,Shi Ruhua,Gu Tainyi,Wei Xian,Zhao Jiaqing,Chao Ming,Zhang Qian,Yang Ruizhi
A microporous layer (MPL) with appropriate aperture and hydrophobicity is key for proton-exchange membrane fuel cells (PEMFCs). The MPLs are typically prepared from mixing carbon black and a hydrophobic agent (i.e., polytetrafluoroethylene) physically followed by annealing at elevated temperatures, resulting in pore blockage and carbon black aggregation. To address this issue, we report a facile method to fabricate uniform porous carbons (UPCs) with single aperture and hierarchical porous carbon (HPC) with multiple apertures using a hard silica template followed by chemical grafting with hydrophobic fluoroalkylsilane (FAS-17). An advanced MPL (GMPL) is fabricated by direct layer-by-layer construction of hydrophobic UPC with different apertures, demonstrating improved water drainage and efficient gas transportation, thereby delivering high output power density of 809.64 mW·cm −2 . The as-fabricated GMPL demonstrates superior performance as compared to the one containing MPL prepared with HPC (HPC-MPL, 781.20 mW·cm −2 ) and the ones employing MPL with a single aperture (714.38–749.89 mW·cm −2 ). The controllable gradient aperture, superhydrophobicity, and open pore/channels contribute to the high performance of PFMFC. This work presents a feasible structural design for MPLs toward high-performance PEMFC. Graphical abstract
研究领域:
材料科学
·
化学工程
·
能源技术
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纳米技术
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电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）