Nanomaterials
·
2023
·Vol. 13
·期 2
·266
·
IF 5.3
Erli Qu,Min Xiao,Dongmei Han,Sheng Huang,Zhiheng Huang,Wei Liu,Shuanjin Wang,Yuezhong Meng
A semi-aromatic polybenzimidazole (DPBI) is synthesized via polycondensation of decanedioic acid (DCDA) and 3,3-diaminobenzidine (DAB) in a mixed phosphorus pentoxide/methanesulfonic acid (PPMA) solvent. Ascribing to in-situ macromolecular crosslinker of ploly((vinylbenzyl chloride) (PVBC), a robust crosslinked DPBI membrane (DPBI-xPVBC,xrefers to the weight percentage of PVBC in the membrane) can be obtained. Comprehensive properties of the DPBI and DPBI-xPVBC membranes are investigated, including chemical structure, antioxidant stability, mechanical strength, PA uptake and electrochemical performances. Compared with pristine DPBI membrane, the PA doped DPBI-xPVBC membranes exhibit excellent antioxidative stability, high proton conductivity and enhanced mechanical strength. The PA doped DPBI-10PVBC membrane shows a proton conductivity of 49 mS cm−1at 160 °C without humidification. Particularly, it reveals an enhanced H2/O2single cell performance with the maximum peak power density of 405 mW cm−2, which is 29% higher than that of pristine DPBI membrane (314 mW cm−2). In addition, the cell is very stable in 50 h, indicating the in-situ crosslinked DPBI with a macromolecular crosslinker of PVBC is an efficient way to improve the overall performance of HT-PEMs for high performance HT-PEMFCs.Keywords:polybenzimidazole;crosslinked membrane;high temperature proton exchange membrane;high temperature fuel cell
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 28
·17243-17251
·
IF 10.7
Sifan Chen,Zhuang Ma,Jialin Zhang,Jianchun Niu,Shuomeng Zhang,Qinghua Zhang,Shiyuan Chen,Shanfu Lu,Miao Wang,Qinggang He
Proton-exchange membranes are considered the core of high-temperature proton-exchange membrane fuel cells (HT-PEMFCs) and determine the output power of the cells. However, current HT-PEMs, which are mainly doped with phosphoric acid (PA), face challenges such as low conductivity and loss of PA during cell operation. In this study, cardo poly(biphenyl indole) membranes (POXIA-QA) with quaternary ammonium salt terminals and tunable side-chain lengths were designed at the molecular level. The rational structural design enabled PA to form a continuous hydrogen-bonding network in POXIA-QA, which could be effectively immobilized and retained. The proton conductivity and activation energy patterns were found to be inconsistent with the PA doping level, suggesting that proton transportation depends not exclusively on the amount of PA but also on the PA distribution induced by the acidic spacer. The polymer membrane bearing a hexyl side chain spacer exhibited excellent proton conductivity (0.113 S cm−1 at 180 °C) and single-cell power density (1001.3 mW cm−2 at 180 °C). This study provides insights into the microphase separation, PA distribution, proton transfer, and high-temperature fuel cell performance of phosphonic acid-doped HT-PEMs with side chains and establishes structure–performance relationships. This study is expected to provide a theoretical basis and suitable candidate materials for the design of HT-PEMs.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Guoxiao Xu,Shiji Xue,Zenglv Wei,Jing Li,Konggang Qu,Ying Li,Weiwei Cai
With PWA as proton transfer and silica as water retainer, stable phosphotungstic acid/silica/Nafion (PWA/Si–N) composite membrane is non-destructively fabricated and exhibits excellent stability and high temperature proton conductivity . Compared with pristine Nafion , high temperature proton conductivity is significantly enhanced due to the collaboration between –SO 3 H ionic clusters and the in -situ filled silica embedded PWA nanoparticles . PWA is stabilized in the ionic clusters via in-situ catalyzing the hydrolysis silica precursor targeted filled into the –SO 3 H ionic clusters. Stable proton conductivity of the PWA/Si–N membrane at 110 °C and 60% RH is high to 0.058 S/cm, which is 2.4 folds of that of Nafion. At the same time, the composite membrane still maintains good mechanical and thermal stability. As a result, high temperature fuel cell performance of the composite membrane is improved by 41% compared with the pristine Nafion membrane . The in -situ coating method proved to be an effective method to solve the stability of PWA in Nafion membrane, especially the inorganic oxide with good hygroscopicity as the modifier.
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
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Huijuan Bai,Haining Wang,Jin Zhang,Chunxiao Wu,Jujia Zhang,Yan Xiang,Shanfu Lu
The development of high temperature proton exchange membranes (HT-PEMs) with high proton conduction and excellent mechanical properties remains a challenge. Herein, the graphitic carbon nitride (CN) nanosheets were successfully introduced into poly(ether sulfones)-poly(vinyl pyrrolidone) polymer matrix to prepare composite membrane through a facile blending method. The synthesized CN nanosheets were characterized by scanning electron microscope (SEM), Transmission electron microscopy (TEM), Raman spectrum, and X-ray photoelectron spectroscopy (XPS). The proton conductivity of the composite membrane was improved up to 36% (0.104 S cm −1 ) after incorporating CN nanosheets at 160 °C, due to increased PA doping level and faster proton dissociation. Meanwhile, the tensile strength of the composite membrane is increased of 60% (6.0 MPa) compared to that of pristine membrane, because of the physical reinforced effect from the 2D structure of CN. Furthermore, the single cell fabricated with the optimized membrane exhibits a peak power density of 512 mW cm −2 at the temperature of 160 °C for 200 h with no obvious loss of current density.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2018
·
IF 6.945
Xiaobai Li,Peng Wang,Zhenchao Liu,Jinwu Peng,Chengying Shi,Wei Hu,Zhenhua Jiang,Baijun Liu
Phosphoric acid-doped polybenzimidazole membranes offer great potential for high-temperature proton exchange membrane applications due to their high proton conductivity at high-temperature and low-humidity conditions. However, it remains a major challenge in fabricating high-performance membranes with both high proton conductivity and good mechanical strength . Here, a series of polybenzimidazoles with increased imidazole groups are obtained by incorporating some benzimidazole groups onto an arylether-type polybenzimidazole backbone via a simple and efficient N-substituted reaction without catalyst. This arylether-type polybenzimidazole is verified to exhibit good solubility under extremely high molecular weight , and it provides the possibility for fabricating the high mechanical strength membranes at high phosphoric acid doping levels. It is of interest to find that the introduction of additional bulky benzimidazole moieties even enhance the mechanical strength of the membranes, and at the same time, significantly improve their acid doping levels, acid doping rate and proton conductivity. Importantly, the acid-doped grafted membranes show superior dimensional-mechanical stability even at high acid loading. With an acid doping level of 22.1, the grafted membrane displays a high conductivity of 212 mS cm −1 at 200 °C without humidification . A H 2 /O 2 fuel cell based on this membrane has a peak power density of 443 mW cm −2 at 160 °C.
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 Energy Chemistry
·
2023
·
IF 13.1
Taizhong Zhu,Danyi Zhu,Jiazhen Liang,Liang Zhang,Fei Huang,Lixin Xue
High-temperature proton exchange membrane fuel cells (HT-PEMFC) possess distinct technical advantages of high output power, simplified water/heat management, increased tolerance to fuel impurities and diverse fuel sources, within the temperature range of 120–200 °C. However, for practical automobile applications, it was crucial to broaden their low-temperature operating window and enable cold start-up capability. Herein, gel-state phosphoric acid (PA) doped sulfonated polybenzimidazole (PBI) proton exchange membranes (PEMs) were designed and synthesized via PPA sol-gel process and in-situ sultone ring-opening reactions with various proton transport pathways based on absorbed PA, flexible alkyl chain connected sulfonic acid groups and imidazole sites. The effects of flexible alkyl sulfonic acid side chain length and content on PA doping level, proton conductivity, and membrane stability under different temperature and relative humidity (RH) were thoroughly investigated. The prepared gel-state membranes contained a self-assembled lamellar and porous structure that facilitated the absorption of a large amount of PA with rapid proton transporting mechanisms. At room temperature, the optimized membrane exhibited a proton conductivity of 0.069 S cm −1 , which was further increased to 0.162 and 0.358 S cm −1 at 80 and 200 °C, respectively, without additional humidification. The most significant contribution of this work was demonstrating the feasibility of gel-state sulfonated PBI membranes in expanding HT-PEMFC application opportunities over a wider operating range of 25 to 240 °C.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-12
·
IF 15.7
Yang Hongxin,Zhang Yuan,Liu Zhipeng,Hu Chunfang,Li Junbiao,Liao Hailong,Shao Minhua,Ni Meng,Chen Bin,Shao Zongping,Xie Heping
Thermo-mechanics of cathode is closely related to the durability of high-temperature solid oxide fuel cells (SOFCs), with two main mechanical failures during thermal cycling: interface delamination and bulk cracking of cathode. Bulk cracking, caused by insufficient fracture strength/stiffness is a big concern but often overlooked. Here, we introduce chemical hydration to offset the thermal expansion, enhancing the cathodic mechanical stiffness and fracture strength, thus promoting the thermo-mechanical durability of cathode in proton ceramic fuel cells (PCFCs). Such chemical-induced expansion offset is achieved by strengthening intergranular bonding inside the bulk cathode after the hydration, preventing granule detachment during thermal shrinkage. As a demonstration, the stiffness-enhanced air electrode (BaCo 0.7 Ce 0.15 Y 0.15 O 3 , noted as s-BCC-Y) exhibits 86% enhancement of fracture strength, thus thermal cycling stability with almost no degradation after 35 harsh thermal cycles between 600 and 300 °C, surpassing pristine BaCo 0.7 Ce 0.3 O 3 and many cobalt-free PCFC cathodes. Benefitted from the improved stiffness of cathode, full cell with the s-BCC-Y electrode demonstrates enhanced power output. This work highlights the importance of bulk cathode thermo-mechanics in developing robust SOFCs for high temperature energy applications.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Bowen Zheng,Chengwei Deng,Ruoyin Luo,Shaojie Gao,Feng Ji,Dong Wang
To simultaneously increase the mechanical strength and proton conductivity of Phosphoric acid-doped polybenzimidazole (PA-PBI), a facile two-step crosslinking approach is proposed to prepare the imidazole-rich crosslinked polybenzimidazole membranes for high-temperature proton exchange membrane fuel cells (HT-PEMFCs) in this work. Unlike the classic crosslinking approaches that usually enhance mechanical strength of membrane but lead to a decrease of proton conductivity, the mechanical strength of two-step crosslinked membrane improves from 3.93 MPa to 9.62 MPa and proton conductivity increases from 91 mS cm −1 to 183 mS cm −1 at 200 °C compared with pristine OPBI membrane. The promotion should be ascribed to the introduction of PA-affinity sites on crosslinkers and the formation of homogeneous crosslinking networks. Meanwhile, due to the crosslinked networks, the oxidative and dimensional stability of crosslinked membranes are also promoted. In addition, the two-step cross-linking method can avoid the self-reaction between cross-linking agents, thereby obtaining a more uniform cross-linking network, which is of great significance for the use of fuel cells. When the membranes are used in a fuel cells, they exhibited a maximum power density of 448.8 mW cm −2 at 160 °C (H 2 /Air, without humidification.).
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
International Journal of Polymer Science
·
2024
·
IF 3.4
Shuangjie Liu,Jialin Yu,Yongping Hao,Feng Gao,Mo Zhou,Lijun Zhao
Using Nafion212 membrane and TEOS solution as raw materials, Nafion212/SiO2 composite membranes were prepared. In the in situ sol-gel reaction process, a series of Nafion/SiO2 composite membranes were prepared by varying the reaction temperature and reaction time. The effects of different modification schemes on Nafion/SiO2 composite membranes were studied using SEM, EDS, TEM, TGA, XRD, and mechanical tensile experiments, among other methods. The results show that Nafion/SiO2 composite membranes prepared at 3°C exhibit a well-separated phase structure and excellent water retention properties, with a water uptake of 29.23% and a swelling ratio of 24.25%. These membranes also demonstrate outstanding physical and chemical performance, with a maximum tensile stress of 13.6 MPa and an elongation at a break of 270%. At 110°C, the proton conductivity of the Nafion/SiO2 composite membrane reaches 0.172 S/cm, meeting the requirements for high-temperature proton exchange membrane fuel cells.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2018
·Vol. 33
·期 1
·212-220
·
IF 0.524
Liu Qingting,Ni Na,Sun Quan,Wu Xiaoxue,Bao Xujin,Fan Zhang,Zhang Rong,Hu Shengfei,Zhao Feng,Li Xiao
Novel organic-inorganic composites were in-situ synthesized by using TriSilanolPhenyl polyhedral oligomeric silsesquioxane (SO-POSS) as fillers and poly(2,5-benzimidazole) (ABPBI) as polymer matrix. The uniformly dispersed 3% SO-POSS particles in ABPBI matrix increased the thermal stability of the composite membranes. It was found that both the water and H 3 PO 4 uptakes were increased significantly with the addition of SO-POSS due to the formation of hydrogen bonds between the POSS and H 2 O/H 3 PO 4 , which played a critical role in the improvement of the conductivity of the composite membranes at temperature over 100 °C. Proton conductivities of H 3 PO 4 doped with 3wt% SO-POSS contained ABPBI membranes increased with the increase of H 3 PO 4 absorbance, reaching the maximum proton conductivity of 2.55 × 10 -3 S·cm -1 at 160 °C, indicating that the ABPBI/SO-POSS composite membrane could be a promising candidate for mid-temperature PEMFCs.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Xueqing You,Qing Ju,Yichang Ma,Guiqin Yi,Zhangtang Jiang,Nanwen Li,Qiugen Zhang
Phosphoric acid (PA)-doped membranes are regarded as a promising candidate for high temperature proton exchange membranes (HT-PEMs), but the trade-off between mechanical property and conductivity is a major problem limiting their application. Here, two poly( meta -terphenyl alkylene)s ( m -TPNs), namely m -TPN-MeIm and m -TPN-TMA, are synthesized by 1-methylimidazole (MeIm) and trimethylamine (TMA) reacting with precursor polymer, respectively. The influence of different cationic groups on the properties of m -TPNs HT-PEMs is investigated in detail. m -TPNs diminish plastication of PA molecules on the mechanical property by separating the adsorption sites for PA molecules from the polymer backbone through long alkyl side chains. As a result, both m -TPN-MeIm and m -TPN-TMA membranes exhibit good mechanical property. Besides, m -TPN-TMA/PA surpasses m -TPN-MeIm/PA in most of aspects owing to the higher ion exchange capacity (IEC) and more distinct microphase separation structure. Noticeably, the proton conductivity of m -TPN-TMA/PA is as high as 0.191 S cm −1 and exhibits excellent stability over a testing time of 100 h at 160 °C thanks to the remarkable acid uptake and microphase separation structure. The m -TPN-TMA/PA-based single cell produces an impressive peak power density of 552 mW cm −2 at 200 °C. Therefore, this work offers a viable alternative for structure design to mitigate the trade-off effect of PA-doped HT-PEMs.
研究领域:
材料科学
·
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Jierui Song,Yiming Xiao,Lei Zhang,Jun Xiang,Na Tang,Penggao Cheng,Jianping Zhang,Songbo Wang,Wei Du
Proton exchange membranes with a wide application temperature range were fabricated to start high-temperature fuel cells under room temperature . The volume swelling stability, oxidative stability as well as mechanical properties of crosslinked membranes have been improved for covalently crosslinking poly(4,4′-diphenylether-5,5′-bibenzimidazole) (OPBI) with fluorine-terminated sulfonated poly(ether ether ketone) (F-SPEEK) via N-substitution reactions. High proton conductivity was simultaneously realized at both high (80–160 °C) and low (40–80 °C) temperatures by crosslinking and jointly constructing hydrophilic-hydrophobic channels. The crosslinked membranes exhibited the highest proton conductivity of 191 mS cm −1 at 80 °C under 98% relative humidity (RH) and 38 mS cm −1 at 160 °C under anhydrous, respectively. Compared with OPBI membrane, the fuel cell performance of the crosslinked membranes showed higher peak power density at full temperature range (40–160 °C).
研究领域:
材料科学
·
化学工程
·
能源技术
✓ 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）