ACS Applied Energy Materials
·
2021
·
IF 6.024
Feng Zhang,Dongqing Zhang,Wenqi Liu,Jiyuan Miao,Xiaojin Li
Developing a feasible method to massively fabricate low-cost and efficient oxygen reduction reaction (ORR) catalysts is highly anticipated to the commercialization of fuel cells. In this work, N atoms were doped into inert sp2 configuration to alter the spin and charge distribution in the carbon matrix. The Pt/H2–N–C catalyst was successfully prepared by embedding ultralow Pt nanoparticles on N-based carbon. Results indicated that the protonated N-groups at edge sites efficiently regulated the absorption of the PtCl62– anion and widely limited the migration of Pt species at 1000 °C. The acquired Pt/H2–N–C electrocatalyst exhibited high ORR performance in the acidic electrolyte. The high-temperature proton exchange membrane fuel cell (HT-PEMFC) measurement illustrated that the open-circuit voltage and power density of the Pt/H2–N–C catalyst were higher than those of the commercial 20% Pt/C at 150 °C. This work provided a facile strategy to obtain efficient and low-cost Pt catalysts for ORR and HT-PEMFCs.
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
FUEL
·
2025
·
IF 7.5
Yu-Ting Liu,Guo-Bao Huang,Xiao-Fang Zhang,Ting-Ting Yao,Li-Xia Cheng,Hong Zhu,Gang-Ping Wu
Gas diffusion layers (GDLs) are critical to optimizing water management capability; however, carbon papers (CPs), as the substrates that provide channels for two-phase counter flows of reactant gases and product water, have rarely been reported for controlling product water. In this study, gradient pore structures were introduced into CPs for GDLs to control the driving forces of water using the capillary pressure gradient. The results showed that the gradual increase in the pore sizes of the CPs from the microporous layer (MPL) to the bipolar plate (BP) side significantly improved the electrochemical performance, regardless of humidity. At 100 % relative humidity (RH), the maximum power density of the membrane electrode assembly (MEA) whose CP pore sizes gradually increased from the MPL side to the BP side reached 1.78 W·cm −2 under H 2 -O 2 condition, 40.16 % higher than that of the counterpart with uniform CP pore sizes, and 1.28 W·cm −2 under H 2 -air condition, 85.51 % higher than that with uniform CP pore sizes. The maximum current density increases under both wet and dry conditions. The mechanisms revealed that under dry conditions, the relatively smaller pores in the CPs close to the MPL side enhanced the water retention and thus maintained the proton conductivity; under wet conditions, the CP pores that were gradually enlarged from the MPL to the BP side enabled the capillary pressure gradient to guide the product water from the MPL flowing into and through the CP, and thus out of the GDLs.
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 NANOSCIENCE AND NANOTECHNOLOGY
·
2019
·Vol. 19
·期 2
·877-881
·
IF 1.093
Huynh Tai Thien,Pham Hau Quoc,Nguyen At Van,Nguyen Son Truong,Bach Long Giang,Ho Van Thi Thanh
In this work, mesoporous Ti0.7W0.3O2 materials with high conductivity and surface area as promising catalyst support for Pt in Proton-Exchange Membrane Fuel Cells (PEMFCs) were synthesized via a single-step solvothermal process at low-temperature without
using any surfactants or stabilizers. The characterizations of material are measured via XRD, TEM, SEM-EDS, and BET as well as electronic conductivity measurement. As a result, Ti0.7W0.3O2 formed a homogenous solid solution with mesoporous anatase-TiO2
structure and uniformly spherical nanoparticles morphology of about ~10 nm diameter, together with a high electrical conductivity of 0.022 S/cm compared to that of undoped-TiO2 (1.37×10−7 S/cm), which implied that tungsten (VI) ions was successfully doped
into anatase-TiO2 lattices. The N2 adsorption/desorption isotherms indicated that Ti0.7W0.3O2 is being mesoporous structure with high surface area up to ~202 m2/g, which is nearly similar to that of the commercial Vulcan XC72
(~232 m2/g). The Pt nanoparticles was easily anchored onto Ti0.7W0.3O2 surface by the chemical reduction process using NaBH4 as a reducing agent. The spherical Pt nanoparticles of ~9 nm in diameter were deposited uniformly on the mesoporous support.
These results suggested that mesoporous Ti0.7W0.3O2 materials synthesized are promising catalyst supports to replace carbon-based supports for Proton-exchange membrane fuel cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Siqi Fang,Guoliang Liu,Minghai Li,Haining Zhang,Jun Yu,Fangfang Zhang,Mu Pan,Haolin Tang
Reducing the local oxygen transport resistance in the cathode catalyst layer of the proton exchange membrane fuel cell (PEMFC) is crucial for the improvement of cell performance, particularly for low platinum loading. In this work, we report that the performance of PEMFC can be significantly improved by replacing Nafion with a highly oxygen-permeable perfluoronated ionomer containing dioxole segments on the backbone as both proton conductor and catalyst binder in the cathode catalyst layer, as evidenced by the increased peak power density of 100 mW cm–2. Molecular dynamics simulation results reveal that the synthesized ionomer has higher diffusion coefficient and higher oxygen solubility compared with Nafion. Benefiting from the high oxygen permeability, both the specific activity and mass specific activity of a Pt/C catalyst using the designed ionomer as catalyst binder for the oxygen reduction reaction are three times higher than those of a catalyst using Nafion as catalyst binder. The results demonstrate that the rational design of highly oxygen-permeable ionomers applied in the catalyst layer could be an effective strategy for a high-performance PEMFC with low platinum loading.
研究领域:
能源科学
·
材料化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Taipu Chen,Lei Chen,Yutong Zhao,Jinkai Hao,Zhigang Shao
To tackle the challenges of phosphoric acid (PA) leakage and suboptimal proton transfer efficiency in PA-polybenzimidazole (PBI) high-temperature proton exchange membranes (HTPEMs), this research has pioneered the development of a novel porous silicon material, DP/S15, which has been tailored through organic phosphonic acid modification. S15 or DP/S15 was utilized to fabricate PBI composite membranes and subjected these membranes to a thorough examination of their properties. The integration of DP/S15 into the membrane matrix notably enhanced acid uptake and facilitated the formation of a robust and extensive proton transportation network. This was largely attributable to the synergistic interaction between the organic phosphonic acid groups in DP/S15 and PA. As a result, the membranes incorporating DP/S15 exhibited a host of commendable properties, most notably their substantial mechanical strength , which registered at 89.80 MPa with undoped PA and 13.10 MPa with doped PA. Furthermore, theoretical analyses lent credence to the efficient adsorption between DP/S15 and phosphoric acid. Consequently, the composite membranes delivered superior performance metrics, evident in their high conductivity (reaching 57.7 mS cm −1 at 160 °C) and excellent PA retention capabilities (up to 89.5 %). Of paramount significance was the performance of the single fuel cell equipped with the PA-DP/S15-PBI composite membrane, which achieved a peak power density of 672.29 mW cm −2 . This figure impressively surpassed that of the pure PBI membrane by 262.23 mW cm −2 . In light of these promising outcomes, the PA-DP/S15-PBI composite membrane harbors significant potential for deployment in HT-PEMFCs.
研究领域:
材料科学
·
能源工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2019
·Vol. 126
·期 1
·1-14
·
IF 1.784
Zhou Haikun,Gao Pingping,wang Pan,Xie Zhiyong,Wu Xiaobo
Titanium nitride (TiN) nanoparticles (NPs) were added into polytetrafluoroethylene (PTFE) emulsion for the hydrophobic treatment of carbon papers (CPs). The addition of the nano-sized conducting nanoparticles in impregnation solution could improve the corrosion resistance, electrical conductivity, hydrophobicity and durability of the treated CPs. It is found that the corrosion resistance and electrical conductivity of the as-treated CPs increased gradually as the increment of TiN content. CPs impregnated with PTFE emulsion containing 8 wt% TiN NPs displayed the optimal improved corrosion resistance with corrosion potential and corrosion current density at 0.16 V and 0.056 μA/cm 2 , respectively. Characterizations by SEM, Raman and XPS demonstrate that this improvement is associated with the formation of TiN coating and the improved distribution of PTFE on CPs.
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 Materials Chemistry A
·
2019
·Vol. 7
·期 25
·15288-15301
·
IF 10.733
Xiaoxiao Zhang,Xudong Fu,Shoukun Yang,Yuanfang Zhang,Rong Zhang,Shengfei Hu,Xujin Bao,Feng Zhao,Xiao Li,Qingting Liu
For the application of proton exchange membrane fuel cells (PEMFCs) in a wide temperature range, an ionogel incorporated into poly(2,5-benzimidazole) (ABPBI) membranes with low phosphoric acid doping levels was designed. The natural sepiolite was first acid-treated to obtain one-dimensional silicon nanorods (SNRs) with a large specific surface area and a hierarchical porous structure. The SNRs were then filled with imidazolium ionic liquid (IL) to prepare IL@SNR ionogels. Analysis of related spectra and thermal behavior verified that the IL molecules were confined in the inner channels of SNRs. The as-prepared IL@SNRs were embedded in the ABPBI to form composite membranes (ABPBI/IL@SNRs) via in situ synthesis. By immobilizing proton conductors, the ABPBI/IL@SNR composite membranes markedly improved proton conductivity with low phosphoric acid doping levels in a wide temperature range. A single-cell based on 5 wt% IL@SNRs embedded in a composite membrane achieved a maximum power density of 0.15 and 0.28 W cm−2 at 80 °C and 180 °C, respectively, with 0% RH. The proton conductivities were comparable to those of Nafion-based PEMFCs under the same temperature and humidity conditions and competed with those of reported polybenzimidazole–inorganic composite membrane-based PEMFCs at high temperatures. By using a facile method to prepare nanostructured fillers, the strategy of avoiding proton carrier wastage can be potentially used in the production of high-performance membranes for PEMFCs.
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 Green Energy
·
2022
·
IF 3.206
Guofu Ren,Zhiguo Qu,Xueliang Wang,Jianfei Zhang
Self-humidification is becoming a popular strategy for water management in proton exchange membrane fuel cells (PEMFCs), owing to the advantages of decreased volume, cost, and parasitic power of the hydrogen fuel cell engine. Membrane dehydration is one of the key issues that seriously affect the performance and lifespan of PEMFCs under low humidity conditions. In this work, an electrospinning approach was employed to fabricate gas diffusion layers (e-GDLs) composed of nanosized carbon fibers with a nanoscale pore structure. Further, a vapor deposition of Dow Corning Sylgard 184 was utilized to apply a hydrophobic coating to enhance the hydrophobicity of the e-GDL. The fabricated e-GDL can help alleviate the dehydration of the catalyst-coated membrane by increasing the breakthrough pressure. The breakthrough pressure of the e-GDL is five folds higher than that of the current commercial GDL, owing to the combined effects of the nanostructure and enhanced hydrophobicity. This superior characteristic is expected to effectively alleviate membrane dehydration under low humidity conditions. In addition, the e-GDL has excellent elastic deformability, which can effectively alleviate the irreversible damage caused by the pre-tightening force in the stack assembly process, thus enhancing the durability and lifetime of PEMFCs.
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
Frontiers of Chemical Science and Engineering
·
2021
·Vol. 16
·期 3
·364-375
·
IF 4.204
Wang Ruiqing,Cao Xiaolan,Sui Sheng,Li Bing,Li Qingfeng
The platinum nanowires have been verified to be a promising catalyst to promote the performance of proton exchange membrane fuel cells. In this paper, accurately controlled growth of nanowires in a carbon matrix is achieved for reducing Pt loading. The effects of formic acid concentration and reaction temperature on the morphology and size of the Pt nanowires, as well as their electrochemical performances in a single cell, are investigated. The results showed that the increase in the formic acid concentration results in a volcano trend with the length of Pt nanowires. With increasing reduction temperature, the diameter of Pt nanowires increases while Pt particles evolve from one-dimensional to zero-dimensional up to 40 °C. A mechanism of the Pt nanowires growth is proposed. The optimized Pt nanowires electrode exhibits a power density (based on electrochemical active surface area) 79% higher than conventional Pt/C one. The control strategy obtained contributes to the design and control of novel nanostructures in nano-synthesis and catalyst applications.
研究领域:
材料科学
·
能源工程
·
催化化学
✓ 已验证
DOI
高影响因子
Materials
·
2021
·Vol. 14
·期 6
·1514
·
IF 3.623
Sitong Chen,Shubo Wang,Xueke Wang,Weiwei Li,Baorui Liang,Tong Zhu,Xiaofeng Xie
We added microencapsulated phase change materials (MPCMs) into the homemade antifreeze fluid to take advantage of the latent heat of phase change materials, and explored the possibility of solving the cold start problem of proton exchange membrane fuel cells (PEMFC) with variable specific heat capacity antifreeze. The physical and chemical properties of the MPCMs and their suspensions were tested, and a PEMFC platform for cold start with a thermal management system was established to compare the exothermic performance of MPCS and commercial antifreeze fluid. According to the output voltage, temperature and polarization curves before and after cold start, the MPCMs has a stronger heat transfer capacity than the commercial antifreeze fluid, and the addition of MPCMs can transform the latent heat generated during the phase transition into apparent specific heat capacity, leading to a better solution to the problem of PEMFC cold start.
研究领域:
能源科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Ruyin Ma,Yijie Si,Yifei Chen,Zhou Sha,Jiahao Feizheng,Daliang Guo,Chengliang Duan,Yinchao Xu,Jing Li,Xin Tong
Carbon paper (CP) is the core component of the gas diffusion layer in proton exchange membrane fuel cell (PEMFC), and the actual operation efficiency of PEMFC was greatly affected by the properties and structure of CP. However, the traditional method of modifying CP with phenol formaldehyde resin (PF) has drawbacks such as high brittleness and poor interface bonding effect. Herein, a novel method for improving the mechanical strength and pore characteristics of CP by modifying PF with nanocellulose is proposed. The results confirmed that the mechanical/electrical properties of CP were greatly changed by the diameters and carboxyl content of nanocellulose. Compared with unmodified CP, the electrical resistivity of CNF10 modified CP was decreased by 23%, and the tensile strength, flexural strength, and gas permeability were increased by 101%, 120%, and 70%, respectively. In addition, the peak power densities of CNF10 modified CP at different anode humidification temperatures (70 °C and 85 °C) were 0.49 W.cm -2 and 0.5 W.cm -2 , respectively, which were 75% and 42% higher than those of unmodified CP, and better than the previous studies (0.458 W.cm -2 ). This simple and controllable modification approach of CP will bring new ideas for developing efficient 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
Nature Communications
·
2022
·Vol. 13
·期 1
·1-13
·
IF 17.694
Tang Hongying,Geng Kang,Aili David,Ju Qing,Pan Ji,Chao Ge,Yin Xi,Guo Xiang,Li Qingfeng,Li Nanwen
A key challenge for fuel cells based on phosphoric acid doped polybenzimidazole membranes is the high Pt loading, which is required due to the low electrode performance owing to the poor mass transport and severe Pt poisoning via acid absorption on the Pt surface. Herein, these issues are well addressed by design and synthesis of effective catalyst binders based on polymers of intrinsic microporosity (PIMs) with strong hydrogen-bonding functionalities which improve phosphoric acid binding energy, and thus preferably uphold phosphoric acid in the vicinity of Pt catalyst particles to mitigate the adsorption of phosphoric acid on the Pt surface. With combination of the highly mass transport microporosity, strong hydrogen-bonds and high phosphoric acid binding energy, the tetrazole functionalized PIM binder enables an H 2 -O 2 cell to reach a high Pt-mass specific peak power density of 3.8 W mg Pt −1 at 160 °C with a low Pt loading of only 0.15 mg Pt cm −2 .
研究领域:
材料科学
·
能源技术
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）