INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Xiaocan Zhang,Jiashu Long,Mengxin Wang,Yiran Liu,Huixiao Ma
Blending metal-organic frameworks to optimize proton transport pathways is one of the strategies to improve the proton conductivity of proton exchange membranes (PEM). In this paper, amino-sulfonic acid bifunctionalized UiO-66 (NUS) by one-pot solvothermal method is synthesized, and sulfonated poly (ether ether ketone)/NUS-X (SPEEK/NUS-X) hybrid membranes are prepared by mixing NUS into SPEEK matrix. Among them, SPEEK/NUS-1.5 has the highest proton conductivity (177.76 mS cm −1 , 70 °C, 100% RH) and maintain a 300 h conductivity stability. And its maximum power density was 423.2 mW cm −2 , exceeding pristine SPEEK by 2.20 times. Compare to the pristine SPEEK membrane, it is interesting to note the disappearance of SAXS scattering peak of SPEEK/NUS-1.5. It is speculated that this phenomenon was caused by the generation of acid-base pairs between –NH 2 and –SO 3 H, and the improved hydrogen bonding network provides more proton transport channels and immobilizes sulfonic acid groups for improved durability. The resultant proton conductivity is stable over 300 h with about 90% retention.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2024
·
IF 3.3
Yifan Wang,Xinyu Zhang,Luyao Wang,Yu Chen,Yi Yu,Enrico Traversa,Nan Yang
Yttrium-doped barium zirconate (BZY) thin films are widely used in the field of hydrogen energy because of their excellent proton conductivity and chemical stability. However, the existence of barium defects in BZY thin films fabricated by pulsed laser deposition (PLD) significantly hinders their intrinsic conductivity. In this regard, regulating the A-site nonstoichiometry for Ba-containing proton conductor oxides could control the proton transport properties. Herein, we used a target compensation strategy to compensate for the Ba loss in BZY thin films. We synthesized a series of nonstoichiometry graded Ba1+xZr0.8Y0.2O3-δ (Ba1+xZrY, 0.0 ≤ x ≤ 0.3) targets for growing Ba1+xZrY (0.0 ≤ x ≤ 0.3) thin films on MgO (100) substrates by PLD. The results show that the conductivity of the Ba1.3ZrY thin films is 1 order of magnitude larger than that of the Ba1·0ZrY thin films, exhibiting also lower activation energy. The structural characterization shows that the target compensation strategy can effectively fill the Ba vacancy and promote the proton transport of the Ba1+xZrY films, mainly attributed to the prolonged Zr–O bond length and increased Y dopant effective concentration.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 16
·8887-8897
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IF 14.511
Donglin Han,Peng Zhong,Xiaorong Zhang,Lulu Jiang
Electrolytes with excellent chemical stability and high proton conductivity are key materials for protonic ceramic fuel cells and electrolyzers. Doping aliovalent cations to increase the number of oxygen vacancies is a common method to increase conductivity. However, determining proper sites for efficient doping is a matter of general concern because in many cases, there are several cation sites in complex oxides. In this work, we used EXAFS analysis to probe the changes in the local structure of proton-conducting pyrochlore oxides, La2(Nb0.4Y0.6)2O7−δ (LNY60) and La2(Nb0.35Y0.65)2O7−δ (LNY65), upon hydration and found that the coordination number of the oxygen sites in the vicinity of La and Y increased after hydration, indicating that these oxygen sites were active for the hydration reaction to introduce protons. Thereafter, the trivalent La sites were doped with divalent Ca, Sr and Ba cations to introduce more oxygen vacancies into the adjacent oxygen sites to facilitate the hydration reaction. As expected, the proton conductivity increased with increasing content of Ca, Sr and Ba. The conductivities of 2.54 at% Ca-doped LNY60 and 0.98 at% Sr-doped LNY65 were both 1.16 × 10−3 S cm−1 at 700 °C, nearly four times higher than those of the pristine oxides. These results indicate that assisted by EXAFS analysis, proper dopant sites can be determined precisely to further elevate proton conductivity in oxides.
研究领域:
材料科学
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化学
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
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2022
·Vol. 51
·期 14
·5561-5566
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IF 4.569
Qiu-Nan Yan,Bin-Wen Liu,Xiao-Ming Jiang,Jin-Xu Zhao,Shao-Min Pei,Wen-Fa Chen,Guo-Cong Guo
Copper chalcogenides have drawn considerable attention due to their prominent semiconducting properties. A new Cu-containing semiconductor, namely, CsCuS4 (1), was obtained by a halide salt flux method. Its structure featured 1D infinite ∞1[CuS4] − chains, where the polysulfide anion S42− was relatively rare in Cu chalcogenides. The compound was multifunctional and exhibited significant photocurrent, humidity sensitivity, and proton conductivity properties. Specifically, it exhibits an “on” state photocurrent response of 0.95 μA cm−2 and an “off” state photocurrent response of 0.55 μA cm−2 with good reversibility. The humidity-sensitive resistance in dry air (10% RH) could reach up to six orders of magnitude higher than that in wet air (100% RH). Compound 1 showed an activation energy of 0.19 eV and may have potential electrochemical applications.
研究领域:
材料科学
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半导体物理
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
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IF 3.83
Wenlong Huang,Yushi Ding,Ying Li,Zezhong Wang
Previously, complex perovskites barium strontium tantalate , i.e., Ba 3 Sr 1.4 T 1.6 O 8.4 (BST40), has exhibited excellent proton conductivity due to its high basicity and oxygen vacancy concentration. Herein, we report proton conduction mechanism of BST40 using brick-layer model and defect equilibria model. Briefly, BST40 is prepared by solid-state synthesis method, resulting in hexagonal perovskite structure with space group of P63/m. Interestingly, grain interior and grain boundary thickness of BST40 are almost equal and the grain boundary conduction mainly dominates the conductivity at T > 500 °C. Total standard molar hydration enthalpy of BST40 and grain interior is found to be −79.6 kJ/mol and −101.3 kJ/mol, respectively. Activation energy for BST40, protons, oxygen-ions, and holes in oxygen-containing humid atmosphere is found to be 0.63 eV, 0.51 eV, 0.92 eV, and 1.08 eV, respectively. These values are higher than corresponding values for the grain interior. At 700 °C, proton transport number of BST40 and grain interior is found to be 0.7 and 0.72, respectively, which is significantly higher than other congeneric complex perovskite-type proton conductors . Overall, these results confirm that BST40 possesses excellent proton conductivity.
研究领域:
材料科学
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物理化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 44
·期 6
·4426-4437
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IF 3.741
Fangyan Cui,Wenyi Wang,Caini Liu,Xingyu Chen,Ning Li
Summary One-dimensional (1D) sodium ligninsulfonate functionalized carbon nanotubes (SCNT), two-dimensional (2D) graphene oxide (GO), and three-dimensional (3D) zirconium-based metal-organic frameworks (UiO-66) are self-assembled as filler materials for proton-exchange membranes (PEMs) because of their potential for extending proton transport pathways. Herein, UiO-66-SCNT and UiO-66-SCNT@GO were prepared by a facile solvothermal synthesis and then the nanohybrid chitosan (CS) PEMs were fabricated via solution casting. The hybrid PEMs with higher ion exchange capacity than the pure CS membrane displayed higher proton conductivity and selectivity. The proton conductivity of nanohybrid membrane doped with 7 wt% UiO-66-SCNT@GO (CS/U-S@GO-7) was enhanced to 64 mS cm −1 at 70°C. Simultaneously, the selectivity was reached 19.4 × 10 4 S s cm −3 and was much higher than the pristine CS membrane (0.13 × 10 3 S s cm −3 ). Moreover, the mechanical properties of all composite membranes were significantly enhanced compared with that of the pure CS membrane. The results showed that our research provided a valuable strategy for designing high-performance CS-based PEMs in direct methanol fuel cell (DMFC). Highlights A simple and facile solvothermal synthesis was used to prepare UiO-66-SCNT@GO. UiO-66-SCNT@GO was introduced into chitosan (CS) matrix to optimize proton transport channels. CS-based hybrid membranes exhibit high proton conductivity and selectivity. CS-based hybrid membranes show low methanol permeability.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Cong Wang,Yexin Shen,Xiuyuan Wang,Yugang Zhang,Chengzhen Wang,Qin Wang,Hui Li,Shuao Wang,Daxiang Gui
Proton conductors are essential functional materials with a wide variety of potential applications in energy storage and conversion. In order to address the issues of low proton conductivity and poor stability in conventional proton conductors, a simple and valid ion-exchange method was proposed in this study for the introduction of stable and ultrahigh proton conductivity in layered rare earth hydroxides (LRHs). Test analyses by solid-state nuclear magnetic resonance, Fourier transform infrared spectroscopy, and powder X-ray diffraction revealed that the exchange of H2PO4– not only does not disrupt the layered structure of LRHs, but also creates more active proton sites and channels necessary for proton transport, thereby creating a high-performance proton conductor (LRH-H2PO4–). By utilizing this ion-exchange method, the proton conductivity of LRHs can be significantly enhanced from a low level to an ultrahigh level (>10–2 S·cm–1), while maintaining excellent long-term stability. Moreover, through methodically manipulating the guest ions and molecules housed within the interlayers of LRHs, a comprehensive explanation has been presented regarding the proficient mechanism of proton conduction in LRH-H2PO4–. As a result, this investigation presents a feasible and available approach for advancing proton conductor.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Jinbao Li,Ning Cui,Di Liu,Zhe Zhao,Fan Yang,Jundong Zhong,Jinhui Pang
Sulfonated poly(ether ether ketone)-poly(ether ketone) (SPEEK-co-PEK-x) copolymers with controlled degree of sulfonation are synthesized by the polycondensation reaction of varying monomer ratios. Compared with the traditional homopolymer sulfonated poly(ether ether ketone) (H-SPEEK), the SPEEK-co-PEK-x copolymer membrane has a high degree of sulfonation and excellent proton conductivity . Meanwhile, it also has favorable mechanical properties and stability. This is attributed to the introduction of the -PEK- segment. The SPEEK-co-PEK-75 membrane exhibits the highest conductivity (0.285 S cm −1 ) at 80 °C, 100% RH and when tests at 80 °C with 80% RH, the SPEEK-co-PEK-75 membrane reaches 0.0587 S cm −1 . In addition, the tensile strength of the SPEEK-co-PEK-75 membrane reaches 47.66 MPa at room temperature . Moreover, the study investigates the impact of key variables on the single-cell performance of SPEEK-co-PEK-x membranes. The measured peak power densities of the SPEEK-co-PEK-75 membrane are 212 mW cm −2 and 495 mW cm −2 at 70% RH and 100% RH, which are 1.3 times and 1.7 times higher than that of the Nafion 117 membrane, respectively. After the 80 h durability test at 80 °C and 80% RH, the voltage of the SPEEK-co-PEK-75 membrane only drops by 4.8%. The presence of the -PEK- segment results in a more compact and connected distribution of hydrophilic ion clusters in the SPEEK-co-PEK-X membrane. This adjustment greatly enhances the performance of the membrane, making it an excellent candidate for proton exchange membrane in H 2 /air fuel cells.
研究领域:
材料科学
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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
·754-763
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IF 3.815
Chen Xing,Xiao Lei,Qiu Xin-Sheng,Chen Kang-Cheng
A series of multiblock sulfonated poly(arylene ether sulfone)s (SPAES) with various block lengths and predictable ion exchange capacity were synthesized from 4,4′-difluorodiphenyl sulfone, 4,4′-dihydrodiphenyl sulfone and 4,4′-biphenol by one-pot and two-pot polymerization. 1 H-NMR and FTIR spectra confirmed the structure that sulfonic acid groups were introduced precisely on the poly(arylene ether sulfone)s by post-sulfonation which resulted in controllable sulfonation degree. The proton exchange membranes (PEMs)-based SPAES displayed excellent dimensional, thermal, antioxidant stability, proton conductivity and mechanical properties (maximum tensile stress >35 MPa). Thermogravimetric analysis indicated the prepared SPAES began to degrade above 310 °C. The effects of polymerization processes, those were, one-pot hydrophobic segment process, one-pot hydrophilic segment process and two-pot process, on the properties of polymers were investigated. The proton conductivity and microphase separation of SPAES PEMs increased in order of those prepared by one-pot hydrophobic segment process, two-pot process and one-pot hydrophilic segment process. The highest conductivities of SPAES synthesized by the above processes under 80 °C and 100% relative humidity were 213 (MS4), 297 (MB3) and 360 mS·cm −1 (MQ2), respectively.
研究领域:
材料科学
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化学工程
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能源技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Feifei Fang,Lu Liu,Luofu Min,Li Xu,Wen Zhang,Yuxin Wang
To increase the conductivity of proton exchange membranes in the membrane thickness direction, a novel mixed matrix membrane of Nafion ionomer and sulfonated graphene nanoplates (sGNP) with aligned proton channels is prepared with the assistance of an electric field. A high voltage alternative electric field is applied to a casting solution consisting of Nafion ionomer , sGNP, N, N-dimethylformamide (DMF), and p-xylene (PX) while evaporating the solvents. The sGNP, naturally attracting the ionic groups of Nafion ionomer to their vicinity, is polarized and rotated under the electric field, leaving aligned proton channels in the solidified membrane. The trans-plane proton conductivity of the mixed matrix membrane can reach 0.155 S cm −1 at 80 °C and 100% RH, an increase of 48% as compared with the conventional cast Nafion membrane . Accordingly, the peak power output of H 2 /O 2 fuel cell with the mixed matrix membrane increases by 15%, reaching 440 mW cm −2 at 80 °C.
研究领域:
材料科学
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能源技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Shubo Wang,Yuan Lin,Jian Yang,Lei Shi,Guang Yang,Xupin Zhuang,Zhenhuan Li
Metal–organic frameworks (MOFs) exhibit high proton conductivity , thermal stability, and offer immense flexibility in terms of tailoring their size. Owing to their unique characteristics, they are desirable candidates for proton conductors . Nevertheless, constructing ordered MOF proton channels in proton exchange membranes (PEMs) remains a formidable challenge. Herein, blend nanofibers of cellulose and UiO-66-NH 2 (Cell–UiO-66-NH 2 ) obtained via the electrospinning process were embedded in a sulfonated polysulfone matrix to obtain high-performance composite PEMs with an orderly arrangement of UiO-66-NH 2 . Comprehensive characterization and membrane performance tests reveal that composite membrane with 5 wt% (nominal) UiO-66-NH 2 have revealed high proton conductivity of 0.196 S cm −1 at 80 °C and 100% relative humidity. Meantime, the composite membrane exhibits a low methanol permeability coefficient (~5.5 × 10 −7 cm 2 s −1 ). Moreover, the composite membrane exhibits a low swelling ratio (17.3%) even at 80 °C. The Cell–UiO-66-NH 2 nanofibers exhibit strong potential for use as a proton-conducting nanofiller in fuel-cell PEMs.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Jie Wang,Chunli Gong,Sheng Wen,Hai Liu,Caiqin Qin,Chuanxi Xiong,Lijie Dong
Recently, fabricating low-cost and high-performance proton exchange membranes (PEMs) with carbon nanotubes (CNTs) and chitosan (CS) have been extensively studied. Herein, we reported a facile but effective method to prepare CS-based PEM with polydopamine (PDA) functionalized CNTs (PDA@CNTs). The CS/PDA@CNTs composite membranes were prepared by incorporating PDA@CNTs into CS matrix followed by ion cross-linking with sulfuric acid. Due to the hydrogen bonding between the CS matrix and PDA coating, the thermal, mechanical and oxidation stability of the CS/PDA@CNTs composite membranes were improved. Moreover, the proton conductivity was also improved owing to the improved dispersion of PDA@CNTs in the CS matrix and the electrostatic interaction between PDA@CNTs and CS matrix. The maximum proton conductivity can reach to as high as 0.028 S cm −1 under 80 °C with 2 wt% loading of PDA@CNTs. These results indicate that the CS/PDA@CNTs composite membranes have great potential to be used as PEMs in fuel cells.
研究领域:
材料科学
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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）