ADVANCED MATERIALS
·
2024
·
IF 27.4
Lingping Zeng,Xiaoli Lu,Caili Yuan,Wei Yuan,Ke Chen,Jingying Guo,Xiaoxi Zhang,Jianchuan Wang,Qiang Liao,Zidong Wei
High-performance proton exchange membrane (PEM) is crucial for the proton exchange membrane fuel cell (PEMFC). Herein, a novel “self-enhanced” PEM is fabricated for the first time, which is composed of perfluorinated sulfonic acid (PFSA) resin and its own nanofibers as reinforcement. With this strategy, the interfacial compatibility issue of conventional fiber-reinforced membranes is fully addressed and up to 80 wt% loading of PFSA nanofibers can be incorporated. Furthermore, on account of chain orientation within the PFSA nanofiber, single fiber exhibits super-high conductivity of 1.45 S cm −1 , leading to state-of-the-art proton conductivity (1.1 S cm −1 ) of the as-prepared “self-enhanced” PEM so far, which is an order of magnitude increase compared with the bulk PFSA membrane (0.29 S cm −1 ). It surpasses any commercial PEM including the popular GORE-SELECT and Nafion HP membranes and is the only PEM with conductivity at 10 0 S cm −1 level. In addition, the mechanical strength and swelling ratio of membranes are both substantially improved simultaneously. Based on the high-performance “self-enhanced” PEM, high peak power densities of up to 3.6 W cm −2 and 1.7 W cm −2 are achieved in H 2 -O 2 and H 2 -Air fuel cells, respectively. This strategy can be applied in any polymeric electrolyte membrane.
研究领域:
材料科学
·
能源工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science Bulletin
·
2020
·
IF 9.511
Shihan Qi,Huaping Wang,Jian He,Jiandong Liu,Chunyu Cui,Mingguang Wu,Fang Li,Yuezhan Feng,Jianmin Ma
Lithium (Li) metal is widely considered as a promising anode for next-generation lithium metal batteries (LMBs) due to its high theoretical capacity and lowest electrochemical potential. However, the uncontrollable formation of Li dendrites has prevented its practical application. Herein, we propose a kind of multi-functional electrolyte additives (potassium perfluorinated sulfonates) from the multi-factor principle for electrolyte additive molecular design (EDMD) view to suppress the Li dendrite growth. The effects of these additives are revealed through experimental results, molecular dynamics simulations and first-principles calculations. Firstly, K + can form an electrostatic shield on the surface of Li anode to prevent the growth of Li dendrites . Secondly, potassium perfluorinated sulfonates can improve the activity of electrolytes as co-conductive salts, and lower the electro-potential of Li nucleation. Thirdly, perfluorinated sulfonate anions not only can change the Li + solvation sheath structure to decrease the desolvation energy barrier and increase the ion migration rate, but also can be partly decomposed to form the superior solid electrolyte interphase (SEI). Benefited from the synergistic effects , an outstanding cycle life over 250 h at 1 mA cm −2 is achieved in symmetric Li||Li cells. In particular, potassium perfluorinated sulfonate additives (e.g., potassium perfluorohexyl sulfonate, denoted as K + PFHS) can also contribute to the formation of high-quality cathode electrolyte interphase (CEI). As a result, Li||LiNi 0.6 Mn 0.2 Co 0.2 O 2 full cells exhibit significantly enhanced cycling stability. This multi-factor principle for EDMD offers a unique insight on understanding the electrochemical behavior of ion-type electrolyte additives on both the Li metal anode and high-voltage cathode.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 26
·11893-11906
·
IF 3.5
Dong Xiaokun,Li Yongzhe,Wei Gang,Zhao Shuhui,Gao Shugang,Gao Jiangshan,He Yan
Carbon quantum dots (CQDs) are compatible with perfluorosulfonic acid (PFSA) polymers due to their rich hydrophilic functional groups and nanoscale particle size, making them suitable as inorganic fillers for proton exchange membranes. In this work, CQDs synthesized by a simple microwave-assisted pyrolysis method were used to improve the performance of PFSA proton exchange membranes. Research indicates that at 80 °C and 100% relative humidity (RH), the proton conductivity of the PFSA membrane increased to 254 mS/cm with the addition of 0.5 wt% CQDs filler, compared to 249 mS/cm for the original PFSA membrane. This enhancement in proton conductivity is likely attributed to the hydrophilic functional groups present on CQDs, such as carboxyl groups (–COOH) and amino groups (–NH 2 ). Furthermore, a notable decrease in hydrogen permeability was observed in the composite membranes due to the incorporation of CQDs. Specifically, the hydrogen permeability of the PFSA/CQDs-2 composite membrane was reduced by approximately 44% compared to the original PFSA membrane. This reduction in hydrogen permeability is likely a result of cross-linking between the sulfonic acid groups in PFSA and the amino groups in CQDs. In conclusion, CQDs contribute to better proton conductivity, lower hydrogen permeability, and enhanced thermal and mechanical stability for PFSA membranes, making them a potential membrane material for high-temperature operation in proton exchange membrane fuel cells.
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
CHINESE JOURNAL OF POLYMER SCIENCE
·
2022
·Vol. 40
·期 7
·764-771
·
IF 3.815
Xu Tang-Cheng,Wang Chang-Shui,Hu Zhao-Yu,Zheng Jiao-Jiao,Jiang Shao-Hua,He Shui-Jian,Hou Hao-Qing
In this work, a series of high strength, thermal stable and antioxidant proton exchange membranes were designed with solution processible polybenzimidazole (PBI) as the matrix and perfluorosulfonic acid (PFSA) as the fortifier for proton exchange. Solution processible PBI was successfully synthesized by introducing 4,4′-dicarboxydiphenyl ether into the molecular chains of PBI. PFSA/PBI composite membranes were obtained by solution blending and film casting. PBI and PFSA/PBI composite membranes exhibited greatly enhanced tensile strength and Young’s modulus compared to PFSA. PFSA/PBI composite membranes are stable below 300 °C which are suitable for practical application in proton exchange membrane fuel cells. The PFSA/PBI composite membranes show good dimensional stability with low water uptake and swelling rate. The PFSA/PBI composite membranes also exhibit excellent antioxidation stability with less than 5% initial mass loss over 120 h in Fenton reagent. The proton conductivity of PBI is greatly enhanced by blending with PFSA and the proton conductivities of the composite membranes are increased with the raise of PFSA content and temperature. This work offers valuable insights into the exploration of PBI based highperformance proton exchange membranes.
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
Polymers
·
2024
·Vol. 16
·期 13
·1863
·
IF 4.7
Yan Qiu,Xinyang Zhao,Hong Li,Sijun Liu,Wei Yu
The viscosity and viscoelasticity of polyelectrolyte solutions with a single electrostatic interaction have been carefully studied experimentally and theoretically. Despite some theoretical models describe experimental results well, the influence of multiple interactions (electrostatic and hydrophobic) on rheological scaling is not yet fully resolved. Herein, we systematically study the microstructures and rheological properties of short-side-chain perfluorosulfonic acid (S-PFSA), the most promising candidate of a proton exchange membrane composed of a hydrophobic backbone with hydrophilic side-chains, in water/2-propanol. Small-angle X-ray scattering confirms that semiflexible S-PFSA colloidal particles with a length of ~38 nm and a diameter of 1–1.3 nm are formed, and the concentration dependence of the correlation length (ξ) obeys the power law ξ~c−0.5consistent with the prediction of Dobrynin et al. By combining macrorheology with diffusing wave spectroscopy microrheology, the semidilute unentangled, semidilute entangled, and concentrated regimes corresponding to the scaling relationships ηsp~c0.5, ηsp~c1.5, and ηsp~c4.1are determined. The linear viscoelasticity indicates that the entanglement concentration (ce) obtained from the dependence of ηspon the polymer concentration is underestimated owing to hydrophobic interaction. The true entanglement concentration (cte) is obtained by extrapolating the plateau modulus (Ge) to the terminal modulus (Gt). Furthermore, Geand the plateau width, τr/τe(τrand τedenote reptation time and Rouse time), scale as Ge~c2.4and τr/τe~c4.2, suggesting that S-PFSA dispersions behave like neutral polymer solutions in the concentrated regime. This work provides mechanistic insight into the rheological behavior of an S-PFSA dispersion, enabling quantitative control over the flow properties in the process of solution coating.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2017
·
IF 6.035
Xuan Zhang,Liang Shen,Wan-Zhong Lang,Yan Wang
In this work, a small amount of hydrophilic perfluorosulfonic acid (PFSA) is incorporated into the polyvinylidene fluoride (PVDF) substrate to develop the high-performance thin-film composite (TFC) membrane for forward osmosis applications. Because of the hydrophilicity and excellent compatibility with PVDF, PFSA not only significantly improves the wettability of the modified membrane substrate, but also well optimizes the pore size by changing the membrane morphology of PVDF/PFSA substrate. These two factors effectively mitigate the water transport resistance and favor the better formation of the polyamide (PA) layer during the interfacial polymerization, thus improving both the water flux and membrane selectivity of the resultant TFC membranes simultaneously. Effects of the PFSA concentration on the overall properties of the modified substrates and corresponding PVDF/PFSA TFC membranes are systematically investigated via various characterizations. Consequently, the PVDF/PFSA TFC membrane achieves a best water flux ( J V ) of 54.4 LMH and a reverse salt flux ( J S ) of 10.9 gMH in AL-DS mode, and a J V of 27.0 LMH with J S of 8.4 gMH in AL-FS mode using deionized (DI) water and 1 M NaCl aqueous solution as the feed and draw solutions respectively. This work may provide a new orientation in developing TFC membranes on the hydrophobic substrate with its intrinsic advantages maximized.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2012
·
IF 3.85
Junkun Tang,Wangzhang Yuan,Jinhui Wang,Junke Tang,Hong Li,Yongming Zhang
Magnetic field treated perfluorosulfonate ionomer (PFSI) membranes (M-PMs) with improved through-plane proton conductivity are facilely fabricated though solvent casting of PFSI/Fe 3 O 4 nanocomposite dispersion without any third additive under magnetic field followed by discarding the Fe 3 O 4 nanoparticles . In the PFSI/Fe 3 O 4 nanocomposite membrane, Fe 3 O 4 nanoparticles are clearly uniaxially aligned by magnetic field. Subsequently, M-PMs are obtained by removing Fe 3 O 4 from the nanocomposite membranes to eliminate the negative effect of Fe 3 O 4 on proton conducting. The effect of magnetic field treatment on M-PMs' performance is investigated by both in- and through-plane proton conductivity. The results demonstrate that the through-plane proton conductivity of the M-PMs prepared from PFSI/Fe 3 O 4 nanocomposite membrane with optimized Fe 3 O 4 content is enhanced, while the in-plane proton conductivity is reduced compared to the pristine PFSI membrane, which indicate through-plane anisotropic phenomenon of proton conducting in the membranes. Such magnetic field treated PFSI membranes exhibit good appropriateness for using in electrochemical applications, for example fuel cells.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Wenshuo Wang,Pengju Pan,Yongzhong Bao
To meet improved requirements for proton-exchange membranes (PEMs) applied in medium- and low-temperature fuel cells, novel PEMs with superior performance are prepared by using commercial perfluorinated sulfonic-acid ionomer (PFSA) and a dopant, tetraphenylporphyrin tetrasulfonic-acid (TPPS). Different from physically blending PFSA with another polymer or a nano-material, the membrane-forming mechanism of TPPS modified PFSA PEMs is highly dependent on the efficient interaction between PFSA and TPPS molecules. The unique three-part nested hydrophilic-hydrophobic-hydrophilic molecular structure of TPPS plays a crucial role in the co-assembly of PFSA with TPPS. The more intensive ionic cross-linking and hydrogen-bond networks are formed through hydrophilic groups in the outer and internal parts of TPPS and sulfonic-acid groups of PFSA. Meanwhile, secondary cross-linking of these hydrophilic groups is induced by rigid hydrophobic groups in the middle part of TPPS. Therefore, these molecular interactions induce the formation of more stable and stronger nano-phase separation with more uniform size. This novel nano-phase separation structure endows PEMs with elevated applicable temperatures, much increased proton conductivity and thus superior fuel cell performances, which are the keys to the development of more advanced hydrogen fuel cells.
研究领域:
材料科学
·
燃料电池技术
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Yufeng Hao,Linjie Zhou,Yanlei Su,Zhongyi Jiang
Surface segregation method based on the collaborative self-assembly principle was proposed to construct anti-fouling membranes with fouling-resistant and fouling-release mechanisms (dual-defense mechanism). Graphene oxides (GO) functionalized with polyethyleneimine (PEI) and perfluorosulfonic acid (PFSA) were added simultaneously into the casting solution to prepare PVDF/PFSA/PEI-GO hybrid membranes through surface segregation along with phase inversion process. The PEI-GO of hydrophilicity and the PFSA of low surface energy were utilized as additives to incorporate dual-defense mechanism for anti-fouling membranes. Furthermore, the synergistic effect of PEI immobilized on GO and sulfonic acid groups on PFSA generated electrostatic interaction, improving the long-term stability of membranes in aqueous environment. In the oil/water separation performance experiments, PVDF/PFSA/PEI-GO-1% membranes exhibited the highest pure water permeability of 406.7 ± 15.6 L m −2 h −1 bar −1 , with flux decay rate ( DR t ) of 8.6%, and flux recovery rate ( FRR ) of 98.6%.
研究领域:
材料科学
·
膜技术
·
环境工程
·
高分子化学
·
界面科学
·
分离工程
✓ 已验证
DOI
高影响因子
Energies
·
2022
·Vol. 15
·期 9
·3405
·
IF 3.252
Xiaoyu Meng,Yinan Lv,Jihong Wen,Xiaojing Li,Luman Peng,Chuanbo Cong,Haimu Ye,Qiong Zhou
Perfluorosulfonic acid (PFSA) polymer is considered as a proton exchange membrane material with great potential. Nevertheless, excessive water absorption caused by abundant sulfonic acid groups makes PFSA have low dimensional stabilities. In order to improve the dimensional stability of PFSA membranes, nanofibers are introduced into PFSA membranes. However, because nanofibers lack proton conducting groups, it usually reduces the proton conductivities of PFSA membranes. It is a challenge to improve dimensional stabilities while maintaining high proton conductivities. Due to the structural designability, covalent organic frameworks (COFs) with proton conductive groups are chosen to improve the overall performance of PFSA membranes. Herein, COFs synthesized in situ on three-dimensional PAN nanofibers were introduced into PFSA to prepare PFSA@PAN/TpPa-SO3H sandwiched membranes. The PFSA@PAN/TpPa-SO3H-5 composite membrane exhibited outstanding proton conductivity, which reached 260.81 mS·cm−1at 80 °C and 100% RH, and only decreased by 4.7% in 264 h. The power density of a single fuel cell with PFSA@PAN/TpPa-SO3H-5 was as high as 392.7 mW·cm−2. Compared with the pristine PFSA membrane, the conductivity of PFSA@PAN/TpPa-SO3H-5 increased by 70.0 mS·cm−1, and the area swelling ratio decreased by 8.1%. Our work provides a novel strategy to prepare continuous proton transport channels to simultaneously improve conductivities and dimensional stabilities of proton exchange membranes.Keywords:electrospinning;perfluorosulfonic acid;nanofibers;covalent organic frameworks;proton exchange membranes;fuel cell;polyacrylonitrile;dimensional stability
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
Nanomaterials
·
2023
·Vol. 13
·期 1
·213
·
IF 5.3
Jisheng Song,Bingkun Huang,Yinyingjie Xu,Kunjie Yang,Yingfan Li,Yuqi Mu,Lingyu Du,Shan Yun,Litao Kang
Even after decades of development, the widespread application of electrochromic windows (ECW) is still seriously restricted by their high price and inadequate performance associated with structural/fabrication complexity and electrochemical instability. Herein, a simple hybrid electrochromic system based on PFSA (perfluorosulfonic acid)-coated Prussian blue (PB, Fe4III[FeII(CN)6]3) film and Ferricyanide–Ferrocyanide ([Fe(CN)6]4−/[Fe(CN)6]3−)-containing hybrid electrolyte is reported. The PB film and the [Fe(CN)6]4−/[Fe(CN)6]3−couple show near redox potentials well inside the electrochemical window of water, resulting in a low driven voltage (0.4 V for coloring and −0.6 V for bleaching) and a relatively long lifespan (300 cycles with 76.9% transmittance contrast retained). The PFSA layer, as a cation-exchange structure, significantly improves the transmittance modulation amplitude (ΔT: 23.3% vs. 71.9% at a wavelength of 633 nm) and optical memory abilities (ΔTretention: 10.1% vs. 67.0% after 300 s open-circuit rest increases) of the device, by means of preventing the direct contact and charge transfer between the PB film and the [Fe(CN)6]4−/[Fe(CN)6]3−couple. This “hybrid electrolyte + electron barrier layer” design provides an effective way for the construction of simple structured electrochromic devices.Keywords:electrochromic;smart window;Prussian blue;[Fe(CN)6]4−/[Fe(CN)6]3−redox couple;perfluorosulfonic acid ion-exchange membrane
研究领域:
材料科学
·
电化学
·
光电
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Composites and Hybrid Materials
·
2023
·Vol. 6
·期 2
·1-14
·
IF 20.1
Zhang Wenxing,Zhao Shengqiu,Wang Rui,Zhang Aojie,Huang Yi,Tang Haolin
The development of rapid and dependable proton transport channels is crucial for proton exchange membrane fuel cells (PEMFCs) operating in low humidity conditions. Herein, a metal–organic framework (NH-Zr framework) consisting of 1H-pyrazole-3, 5-dicarboxylic acid (PZDC), and zirconium chloride octahydrate (ZrOCl 2 ·8H 2 O) rich in basic sites was in situ constructed in a perfluorosulfonic acid (PFSA) solution, and hybrid proton exchange membranes were prepared (PFSA-NH-Zr). The introduced NH-Zr framework successfully induced proton conducting groups (-SO 3 H) reorganization along the NH-Zr framework, resulting in the formation of fast ion transport channels. Meanwhile, under low humidity, the acid–base pairs between N–H (NH-Zr framework) and -SO 3 H (PFSA) promoted the protonation/deprotonation and the subsequent proton leap via the Grotthuss mechanism. Especially, the hybrid membrane PFSA-NH-Zr-1 with suitable NH-Zr content had a promising proton conductivity of 0.031 S/cm at 80 °C, 40% relative humidity (RH), and 0.292 S/cm at 80 °C, 100% RH, which were approximately 33% and 40% higher than the pristine PFSA membrane (0.023 S/cm and 0.209 S/cm), respectively. In addition, the maximum power density of the hybrid proton exchange membrane was 0.726 W/cm 2 , which was nearly 20% higher than the pristine PFSA membrane (0.604 W/cm 2 ) under 80 °C, 40% RH. Thus, PFSA-NH-Zr may be promising membrane materials for potential applications in fuel cells. This work established a referable strategy for developing high-performance proton exchange membranes under low RH conditions. Graphical Abstract
研究领域:
材料科学
·
化学
·
能源工程
✓ 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）