MOLECULES
·
2023
·Vol. 28
·期 6
·2810
·
IF 4.6
Chang Liu,Shang Li
We developed an integrated gas diffusion layer (GDL) for proton exchange membrane (PEM) fuel cells by growing carbon nanofibers (CNFs) in situ on carbon paper via the electro-polymerization of polyaniline (PANI) on carbon paper followed by a subsequent carbonization treatment process. The CNF/carbon paper showed a microporous structure and a significantly increased pore volume compared to commercial carbon paper. By utilizing this CNF/carbon paper in a PEM fuel cell, it was found that the cell with CNF/carbon paper had superior performance compared to the commercial GDL at both high and low humidity conditions, and its power density was as high as 1.21 W cm−2at 100% relative humidity, which is 26% higher than that of a conventional gas diffusion layer (0.9 W cm−2). The significant performance enhancement was attributed to a higher pore volume and porosity of the CNF/carbon paper, which improved gas diffusion in the GDL. In addition, the superior performance of the cell with CNF/carbon paper at low relative humidity demonstrated that it had better water retention than the commercial GDL. This study provides a novel and facile method for the surface modification of GDLs to improve the performance of PEM fuel cells. The CNF/carbon paper with a microporous structure has suitable hydrophobicity and lower through-plane resistance, which makes it promising as an advanced substrate for GDLs in fuel cell applications.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2023
·
IF 5.4
Haifeng Bian,Yanyan Du,Yilun Ren,Hao Wu,Yujie Ma,Beibei Yang,Shaochun Tang,Duan Bin,Hongbin Lu,Xiangkang Meng
Polypyrrole (PPY) coating is promising for the anticorrosion of stainless steel (SS) bipolar plates (BPs) in virtue of its good conductivity and corrosion resistance . However, the poor adhesion and pore defects of pure PPY coating limit its application. In this work, a PPY/Ti 3 C 2 T x MXene composite coating was synthesized on 304SS BPs by one-step electrodeposition , which is a facile method to realize the polymerization of PPY and the doping of MXene at the same time. The PPY/MXene coating exhibits better long-term immersion stability in simulated proton exchange membrane fuel cell (PEMFC) environment than pure PPY. The enhanced corrosion resistance is mainly benefited from the enhanced barrier effect, anodic protection effect and adhesion by the introduction of MXene. Meanwhile, the introduction of MXene significantly improves the conductivity of the coating and decreases the interfacial contact resistance at 1.4 MPa from 108.16 mΩ·cm 2 to 55.24 mΩ·cm 2 .
研究领域:
材料科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 26
·21617-21623
·
IF 3.289
Yong You,Chenghao Wu,Yingfang Yao,Jianguo Liu,Zhongwei Wang,Lin Huang,Jin Xie,Xiaogang Su,Zhigang Zou
The prohibitive cost and scarcity of the precious metals used for oxygen reduction reaction (ORR) catalysts limit the large-scale commercialization of proton exchange membrane fuel cells (PEMFCs). Great efforts have been made to improve the ORR activity of non-precious metal catalysts. Herein, we describe a one-pot synthesis process of preparing triazine-polymer–Fe–C catalysts using polyimide (PI), ferric chloride and melamine as the precursors with a pronounced electrocatalytic activity towards ORR in acid media. The ORR activity of catalysts and the performance of single cells strongly depend on the properties of the carbon supports, which affect the surface areas and microporosities of the final catalysts. The optimized PI–Fe–C catalyst exhibits an excellent performance (onset potential of 0.92 V and the half-wave potential 0.78 V) towards ORR activity in acid medium. A maximum power density of 310 mW cm−2 is obtained with a loading of 2 mg cm−2 in a single cell.
研究领域:
材料科学
·
电化学
✓ 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
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Yanwei Zeng,Huaijie Cao,Wenhu Jia,Yulin Min,Qunjie Xu
Aluminum alloy plates used in proton exchange membrane fuel cells fail to provide long-term stability due to the corrosion. Here, a nitrogen doped carbon film derived from chitosan macromolecule is prepared on Al alloy to improve anti-corrosive ability by spraying and calcining process. Electrochemical tests of the as-prepared carbon film are investigated in a simulated environment of fuel cells (0.5 M H 2 SO 4 + 2 ppm HF). As results, the corrosion potential of the carbon film coated Al alloy shows a positive shift by 157 mV. Its corrosion current density is ~3 orders of magnitude lower than bare Al alloy. Impedance modulus at 0.01 Hz of the coated Al alloy is remarkably improved and it shows a high coating resistance. Furthermore, the carbon film still exhibits a high coverage on the substrate after 50 times peeling off by scotch tape. The high protection efficiency of the carbon film in the acidic condition is attributed to the strong adhesion to the Al alloy and the physical barrier effect. This strategy provides an eco-friendly and facile method for designing a protective coating on Al alloy used in the acidic environment.
研究领域:
材料科学
·
电化学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 24
·12885-12895
·
IF 11.9
Erli Qu,Geng Cheng,Min Xiao,Dongmei Han,Sheng Huang,Zhiheng Huang,Wei Liu,Shuanjin Wang,Yuezhong Meng
A novel acid-base composite membrane consisting of acidic carboxyl-containing polyimide (PI-COOH) and basic polybenzimidazole (OPBI) was fabricated and employed as a high-temperature proton exchange membrane (HT-PEM). PI-COOH was used to prepare HT-PEMs for the first time. The PBI-based acid-base composite membranes and ordinary composite membranes were investigated to elucidate the correlation between the polymer structure and membrane properties, especially in situations where phosphoric acid (PA) is used. The results show that OPBI-xPI-COOH composite membranes (x represents the weight percentage of PI-COOH in the entire membrane) deliver high proton conductivities and superior PA retention due to the continuous hydrogen bond network between OPBI and PI-COOH. The OPBI-50PI-COOH composite membrane revealed a proton conductivity of 89 mS cm−1 under low PA uptake (109%). Compared to the linear OPBI and OPBI-40PI composite membrane, a single cell with a low PA-doped OPBI-50PI-COOH composite membrane presented superior durability and power density (463 mW cm−2) at 160 °C and 0% relative humidity. In a short-term durability test of 369 h, the voltage attenuation rate was only 119 μV h−1. These outstanding outcomes indicate that the obtained acid-base composite membranes can be considered as capable candidates for HT-PEMs with enhanced performance.
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
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Shi-Long Xu,Peng Yin,Lu-Jie Zuo,Shi-Yi Yin,Yue Lin,Wanqun Zhang,Sheng-Qi Chu,Hai-Wei Liang,Xian-Zhu Fu
Proton exchange membrane fuel cells (PEMFCs) as electrochemical-generating devices with zero contaminants can promise a carbon-neutral future, but the usage of the costly platinum group metal catalysts hindered the widespread adoption of PEMFCs. Here, we present the synthesis of a highly active low-Pt PtCu3 intermetallic oxygen reduction catalyst via a sulfur-containing inorganic salt-assisted strategy. We identify that the success of the catalyst synthesis lies in the use of inorganic negative bivalent sulfur salts that leads to the formation of the CuS2 intermediate at low temperatures. The CuS2 intermediate serves as a passivator and releases Cu source at high temperatures to facilitate the formation of the PtCu3 intermetallic catalyst. The prepared small-sized PtCu3 intermetallic catalyst exhibits a high mass-based activity of 3.0 A mgPt–1 and a large electrochemically active surface area of 74 m2 gPt–1 for oxygen reduction, along with an outstanding durability (18% mass activity loss after 30,000 cycles).
研究领域:
材料科学
·
电化学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 5
·571
·
IF 4.501
Yuxin Liu,Jing Ye,Fanpeng Kong,Chunyu Du,Pengjian Zuo,Lei Du,Geping Yin
Proton exchange membrane (PEM) fuel cells using Pt-based materials as electrocatalysts have achieved a decent performance, represented by the launched Toyota Mirai vehicle. The ideal PEM fuel cells consume stored pure hydrogen and air. However, SO2, as a primary air contaminant, may be fed along with air at the cathode, leading to Pt site deactivation. Therefore, it is important to improve the SO2tolerance of catalysts for the stability of the oxygen reduction reaction (ORR). In this work, we develop the Pt/C-TiO2catalyst against SO2poisoning during ORR. Impressively, the hybrid Pt/C-TiO2catalyst with 20 mass % TiO2shows the best ORR and anti-toxic performance: the kinetic current density of ORR is 20.5% higher and the degradation rate after poisoning is 50% lower than Pt/C. The interaction between Pt and TiO2as well as the abundant hydroxyl groups on the surface of TiO2are both revealed to account for the accelerated removal of poisonous SO2on Pt surfaces.
研究领域:
材料科学
·
电化学
·
能源科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 11
·6287-6296
·
IF 3.119
Zhikun Liu,Yanhong Yin,Daijun Yang,Cunman Zhang,Pingwen Ming,Bing Li,Shuting Yang
A simple and efficient method was used to prepare highly active and durable carbon-supported ultrathin Pt–Co nanowires (NWs) as oxygen reduction reaction (ORR) catalysts for the cathode in a proton exchange membrane fuel cell (PEMFC). Chromium hexacarbonyl plays a significant role in making Pt and Co form an alloyed NW, which acts as both a reducing agent and a structure directing agent. The nanocrystal exhibits a uniform nanowire morphology with a diameter of 2 nm and a length of 30 nm. In half cell tests, the Pt–Co NWs/C catalyst has a mass activity of 291.4 mA mgPt−1, which is significantly better than commercial Pt/C catalysts with 85.5 mA mgPt−1. And after the accelerated durability test (ADT), Pt–Co NWs/C shows an electrochemically active surface area (ECSA) loss of 19.1% while the loss in the commercial catalyst is 41.8%. Also, the membrane electrode assembly (MEA) was prepared using Pt–Co NWs/C as the cathode catalyst, resulting in a maximum power density of 952 mW cm−2, which is higher than that of Pt/C. These results indicate that the one-dimensional structure of the catalyst prepared herein is favorable to improve the activity and durability, and the application of the catalyst in the MEA is also realized.
研究领域:
材料科学
·
能源化学
·
电化学
✓ 已验证
DOI
高影响因子
E-POLYMERS
·
2020
·Vol. 20
·期 1
·171-184
·
IF 1.675
Weiye Li,Zhihong Chang,Liming Lin,Xiaoyan Xu
To meet the increasing requirements of membrane humidification in proton exchange
membrane fuel cells (PEMFCs), a series of montmorillonite
(MMT)/PEBAX ® 1074 mixed matrix membranes (MMMs) were fabricated
using the solvent casting method. Pristine MMT and poly(oxyalkylene)amine
(APOP)-modified MMT were added as the filler. Using the XRD, FT-IR, SEM, and TEM, the
morphology and chemical structure of MMT during modification were investigated. Using
the tests of water vapor permeability, air permeability, water contact angle, and
crystallinity, the effects of montmorillonite on membrane properties were
investigated. The results showed that surface hydrophilicity and crystallinity of
MMMs increased as the MMT content increases, which leads to higher vapor permeability
and selectivity than the pure PEBAX ® 1074 membrane. After
modification, APOP-MMT/PEBAX ® 1074 MMMs showed better performance
in vapor permeability and vapor/air selectivity. The best selectivity was 1.7
× 10 5 , which is three times higher than that of pure
PEBAX ® 1074 membrane.
研究领域:
材料科学
·
能源工程
✓ 已验证
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
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Yeyang Li,Junbin Liao,Yueyue Lu,Jiangnan Shen
Ether-free polyaromatic proton exchange membranes (PEMs) are regarded as an optimal and cost-effective substitute for perfluorosulfonic acid membranes due to their excellent oxidation resistance stability, low cost and inherent low permeability. The potential applications of the branched structure are significant in enhancing membrane processability and physical stability, but the ether-free branched sulfonated polyaryl proton exchange membrane remains to be further explored. Herein, we present the synthesis of branched sulfonated poly(isatin terphenyl fluorene) (b-SPITF-x), featuring a branched comb-like structure design incorporating sturdy backbones devoid of ether, branched monomers and flexible side chains containing sulfopropyl groups at specific locations. This branched comb-like structure endows the membrane with sufficient microphase-separated morphology and dense ion clusters, thus ensuring the optimized b-SPITF-10 PEM exhibits simultaneously high H + conductivity (>185 mS cm −1 at 80 °C) and desirable physical properties. Furthermore, the b-SPITF-10 PEMFCs obtained the maximum peak power density of 819 mW cm −2 operated at 80 °C. Moreover, during a 100-h durability test carried out at a temperature of 80 °C, this particular PEM exhibited an impressively low rate of voltage degradation, measuring only 0.743 mV h −1 . The ether-free structure and branched comb-like design offer valuable insights into the advancement of polyaromatic PEMs.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）