COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Bin Wen,Jiahao Feizheng,Ruyin Ma,Daliang Guo,Lizheng Sha,Huifang Zhao,Bei Liu,Yinchao Xu,Jing Li,Tianzhong Yuan,Qianyu Sun
This study developed a novel method to enhance the comprehensive performance of carbon paper (CP) by using aramid nanofibers (ANF) modified phenol formaldehyde resin (PF). The effect of ANF modification ratios (0 wt%, 0.6 wt%, 1.2 wt%, 1.8 wt%, 2.4 wt%) on ANF dispersion in PF impregnation solution, PF thermal stability, and PF carbon matrix structure were investigated. Compared to unmodified PF, ANF-modified PF matrix carbon exhibited increasingly regular and ordered structures, with the I D /I G value decreasing from 2.16 to 2.02. Furthermore, with ANF modification ratio increasing, the tensile strength, flexural strength, porosity and gas permeability of CP exhibited a pattern of initial increase followed by a decrease, and when increasing to 1.8 %, reaching the optimal values of 14.28 MPa, 531.61 MPa, 85.94 %, and 2520 L·m −2 ·s −1 , respectively. The limiting power density of proton exchange membrane fuel cells (PEMFCs) assembled with 1.8 wt% ANF-modified CP gradually increased with different assembly torques of 2, 4 and 6 N·m, reaching maximum values of 0.86, 0.98, and 1.1 W·cm −2 , respectively. Therefore, the novel ANF modification method of CP provides new insights into enhancing PEMFCs assembly adaptability, potentially addressing issues related to low mechanical stability and poor pore structure affecting PEMFCs performance.
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
·
2024
·
IF 8.1
Yuyang Han,Yao Xu,Kai Huang,Fei Xu,Jiayuan Ji,Bencai Lin
A series of imidazolium-functionalized poly(phenylene oxide) (QPPO) cross-linked with polybenzimidazole (PBI) (cQPPOx-PBI) membranes were prepared. Compared to the pure PBI membrane without a cross-linked structure nor imidazolium groups, the cQPPOx-PBI membranes showed enhanced toughness, phosphoric acid (PA) retention, and chemical stability. The cQPPOx-PBI membranes showed a enhanced PA uptake than that of PBI membranes, and the cQPPO35-PBI membrane achieves a high conductivity of 139 mS cm −1 at 160 °C, which is much higher than that of PBI membrane under the same conditions (26 mS cm −1 ). The performance of the single fuel cell assembled with the obtained membranes showed a similar trend as their conductivity, and the cell with cQPPO35-PBI showed a maximum power density of 344 mW cm −2 at 140 °C, while the value for PBI membrane was only 175 mW cm −2 under the same conditions. Herein, a straightforward method was developed for introducing imidazolium groups and cross-linked structures, which can be employed to prepare PEMs with enhanced performance for HT-PEMFCs application.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2022
·
IF 13.7
Zijie Mao,Chen Ding,Xuan Liu,Qing Zhang,Xianxian Qin,Hong Li,Fan Yang,Qing Li,Xia-Guang Zhang,Junliang Zhang,Wen-Bin Cai
The dissolution of M in currently popular Pt–M alloy catalysts (M = Co, Ni, and Fe) during the oxygen reduction reaction (ORR) may deter their wide application in proton exchange membrane fuel cells (PEMFCs). In this work, interstitial B-doping in the Pt lattice is instead used to design a durable and active ORR catalyst, by taking advantage of its unique regulation of the electronic structure of surface Pt sites. 3 nm Pt–B nanoparticles on carbon black (Pt–B/C) are obtained using dimethylamine borane (DMAB) as a reductant and the B source in a mixed H2O–ethylene glycol precursor solution. The formation of the B-doped Pt catalyst is verified by inductively coupled plasma-atomic emission spectrometry, X-ray diffractometry, and spherical aberration-corrected scanning transmission electron microscopy. Both half-cell and single-cell tests indicate that the as-synthesized Pt–B/C catalyst outperforms the commercial Pt/C(com) in terms of activity and durability. In particular, the Pt–B/C-based PEMFC exhibits an initial maximum power density 1.24 times as high as the Pt/C(com)-based one under otherwise same conditions, with a 15% decay for the former versus a 45% decay for the latter after 30 000 cycles of the accelerated degradation test (ADT). Comparative DFT calculations on B-doped and undoped Pt(111) surfaces reveal that the lowered Pt d-band center and the strong interaction of Pt–B bonding weaken the binding of OH and O species to surface Pt sites and lessen oxidative disruption of surface Pt atoms. This interstitial metalloid doping in conjunction with the simple and scalable synthesis protocol enables the Pt–B/C to be a competitive ORR catalyst for the PEMFCs.
研究领域:
材料科学
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能源化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Li Jiang,Junaid Ali Syed,Yangzhi Gao,Qiuxiang Zhang,Junfeng Zhao,Hongbin Lu,Xiangkang Meng
Conductive polymer coating doped with large molecular organic acid is an alternative method used to protect stainless steel (SS) bipolar plates in proton exchange membrane fuel cells (PEMFCs). However, it is difficult to select the proper doping acid, which improves the corrosion resistance of the coating without affecting its conductivity. In this study, large spatial molecular group camphorsulfonic acid (CSA) doped polypyrrole (PPY) conductive coating was prepared by galvanostatic electropolymerization on 304SS. The electrochemical properties of the coating were evaluated in 0.1 M H 2 SO 4 solution in order to simulate the PEMFC service environment. The results indicate that the coating increased the corrosion potential and shifted E corr towards more positive value, particularly the j corr value of PPY-CSA coated 304SS was dropped from 97.3 to 0.00187 μA cm −2 . The long-term immersion tests (660 h) show that the PPY-CSA coating exhibits better corrosion resistance in comparison with the small acid (SO 4 2− ) doped PPY-SO 4 2− or PPY/PPY-SO 4 2− coatings. Moreover, the PPY-CSA coating presents low contact resistance and maintains strong corrosion resistance during the prolonged exposure time due to barrier effect and anodic protection.
研究领域:
材料科学
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电化学
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能源工程
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2020
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IF 4.473
Manojkumar Balakrishnan,Pranay Shrestha,Nan Ge,ChungHyuk Lee,Kieran F. Fahy,Roswitha Zeis,Volker P. Schulz,Benjamin D. Hatton,Aimy Bazylak
We present electrospinning as a versatile technique to design and fabricate tailored polymer electrolyte membrane (PEM) fuel cell gas diffusion layers (GDLs) with a pore-size gradient (increasing from catalyst layer to flow field) to enhance the high current density performance and water management behavior of a PEM fuel cell. The novel graded electrospun GDL exhibits highly robust performance over a range of inlet gas relative humidities (RH). At relatively dry (50% RH) inlet conditions that exacerbate ohmic losses, the graded GDL lowers ohmic resistance and improves high current density performance compared to a uniform GDL with larger pores and fiber diameters. Specifically, the graded GDL facilitates a beneficial degree of liquid water retention at the catalyst layer/GDL interface due to the high capillary pressure inherent in its microstructure, thereby improving membrane hydration. Additionally, enhanced graphitization and connectivity of the graded electrospun fibers improves heat dissipation from the catalyst layer interface compared to the GDL with larger fiber diameters, thereby reducing membrane dehydration. When the inlet RH is raised to fully humid (100% RH) conditions, the graded GDL mitigates liquid water accumulation and lowers mass transport resistance. Specifically, the pore size gradient directs the removal of liquid water from the GDL, resulting in superior performance at high current densities.
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
Sustainable Energy & Fuels
·
2020
·Vol. 4
·期 6
·2859-2868
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IF 5.503
Henghui Huang,Liwen Ni,Jiaoyan Xu,Xiaojun Xie,Li Zhang,Cheng Yang,Jiantao Fan,Hui Li,Haijiang Wang
Highly conductive and water-retentive vinylphosphonic acid-modified aminosilicon oxide cross-linked polymer/perfluorosulfonic acid (VPA-ASOCP/PFSA) membranes were prepared using PFSA solution and vinylphosphonic acid-modified (3-aminopropyl)triethoxysilane (VPA-APTES) as precursors. Spectroscopic and Energy Dispersive Spectrometer (EDS) analyses revealed that in situ generation of a VPA-ASOCP network was effectively achieved along with homogeneous dispersion of silicon backbones and phosphonic acid groups in the PFSA matrix. These composite membranes exhibited an increased water uptake and associated better conductivity at low and medium relative humidity (RH) compared to a pristine PFSA membrane and commercial Gore 740 membrane. The proton conductivity results showed that the VPA-ASOCP/PFSA composite membrane provided a proton conductivity of up to 24 mS cm−1 at 30% RH and 12.4 mS cm−1 at 10% RH, which were respectively 4.8 times and 10.3 times higher than those of the PFSA membrane and 4.5 times and 6.8 times higher than those of the commercial Gore 740 membrane on its own. In addition, the VPA-ASOCP/PFSA composite membrane exhibited superior fuel cell performance and low ohmic resistance across the entire humidity range for fuel cell operation, and the VPA-ASOCP/PFSA composite membrane provided a cell voltage as high as 0.672, 0.664, and 0.648 V at a current density of 1.0 A cm−2 when the RH was 50%, 20%, and 0, which were 50, 71 and 90 mV higher than those of the PFSA membrane and 34, 50 and 72 mV higher than those of the Gore 740 membrane. The water transport and small-angle X-ray scattering experimental results demonstrated that water transport was enhanced and new proton transport channels were formed when the VPA-ASOCP/PFSA composite was used as a proton exchange membrane (PEM). This new type of VPA-ASOCP/PFSA composite membrane is promising for developing PEMs that tolerate variations in humidity.
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
Nanoscale
·
2020
·Vol. 12
·期 27
·14863-14869
·
IF 6.895
Shuli Yin,You Xu,Songliang Liu,Hongjie Yu,Ziqiang Wang,Xiaonian Li,Liang Wang,Hongjing Wang
The development of doped noble metal catalysts with nonmetal elements to improve the catalytic performance toward the oxygen reduction reaction (ORR) is significant for proton exchange membrane fuel cell technology. Here, we report a one-pot for dual-nonmetal-doping strategy for the synthesis of S and P-co-doped mesoporous PtPd nanocages (PtPdSP mNCs) by using pre-synthesized mesoporous PtPd nanocages (PtPd mNCs) as the precursor and triphenylphosphine sulphide as both S and P sources. Benefitting from the combined advantages of metal–nonmetal incorporation, hollow cavity and surface porosity, the resultant quaternary PtPdSP mNCs exhibit outstanding ORR activity and long-term stability. This research work provides a good strategy for the doping of two or more selected nonmetallic elements into metallic nanocrystals with a controllable structure and composition.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2023
·
IF 6.1
Haifeng Bian,Guoli Zhang,Qingxi Zhai,Yanyan Du,Yujie Ma,Beibei Yang,Shaochun Tang,Duan Bin,Xiangkang Meng,Hongbin Lu
Stainless steel (SS) is a promising material for designing bipolar plates (BPs), but their further application is limited by serious corrosion problems in the acidic environment. Ti 3 C 2 T x is expected to be used for SS BPs coatings, while galvanic corrosion will occur after the damage of Ti 3 C 2 T x coating. Herein, a PPY/Ti 3 C 2 T x -AE double-layer coating (DC) is well-designed and prepared on 304SS BP, which is composed of an inner electropolymerized PPY layer and an outer Ti 3 C 2 T x -acrylic epoxy layer. When tested in 0.2 M HCl solution, the corrosion potential and corrosion current density of the DC are 38 mV and 0.00927 μA cm −2 respectively, which are superior to those of the PPY coating and the Ti 3 C 2 T x coating. Moreover, the DC presents the best long-term stability among the three coatings. The excellent corrosion resistance is attributed to the barrier and anodic protection effects as well as the solution of galvanic corrosion. The new coating system provides a new insight into the design of DC coatings of SS BPs.
研究领域:
材料科学
·
电化学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
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
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
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2016
·Vol. 163
·期 7
·F663
·
IF 3.014
Yinshi Li,Yaling He
Contrary to the conventional layer-separated electrode design, we report a metal foam-based all-in-one electrode that incorporates the flow field, backing layer, micro-porous layer, and catalyst layer into a whole. This innovative design facilitates the mass and charge transport as well as extends the three-phase boundary, thereby enabling to miniaturize the cell system while enhance the power output. It has been demonstrated that when applying a pair of 4.0 × 4.0 × 0.5 mm (length × width × height) all-in-one electrodes to the liquid-feed micro polymer electrolyte membrane fuel cell, the peak power density goes up to 123 mW cm−2 even at room temperature, which is much higher than that of the conventional cell system. The present architecture design meets the potential demand of the high-capacity lab-on-a-chip applications.
研究领域:
能源科学
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材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Dongju Fu,Zhao Hu,Jinghui Xun,Xiao Yu,LuYang Wang,Shaozhong Zeng,Fengjiao Li
Highly ordered Pt alloy structure is an effective method to improve the catalytic activity and stability of cathodic oxygen reduction reaction (ORR) in acidic media, which is of great significance for the large-scale commercial application of proton exchange membrane fuel cells (PEMFCs). Herein, a highly efficient and durable catalyst composed of structurally ordered PtCo alloys with nitrogen-doped carbon (NC) shells is designed by improving the impregnation reduction method, using an intermediate self-sacrificial template strategy. Under the optimal preparation conditions of 20 wt% doped Ketjen black and a calcination temperature of 850 °C, the ordered PtCo alloy-based catalyst (denoted as L 1 0 -PtCo/ZNC) is obtained with an average nanoalloy size of about 3.9 nm and uniformly loaded on the N-doped carbon support via pyrolysis of cobalt-based zeolite imidazolate framework (ZIF-67) and carbon black. The half-wave potential ( E 1/2 ) of L 1 0 -PtCo/ZNC reaches 0.927 V vs. RHE, outperforming most of the reported catalysts and the benchmark commercial Pt/C catalyst. Moreover, the mass activity (MA, 1.06 A mg Pt -1 ) and specific activity (SA, 1.03 mA cm -2 Pt ) of L 1 0 -PtCo/ZNC are 7.6 and 4.7 times of those of Pt/C, respectively. The MA and SA values of L 1 0 -PtCo/ZNC after 10,000 cycles are 35 and 23 times of those of Pt/C catalysts, respectively, indicative of the excellent durability of L 1 0 -PtCo/ZNC. This method provides an effective strategy in preparing highly active and stable ordered PtCo alloy-based hybrid catalysts for acid ORR.
研究领域:
材料科学
·
能源化学
·
催化化学
✓ 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
危险品化学品经营许可证（带存储）