JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2022
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IF 10.319
Yaokun Fu,Lu Zhang,Yuan Li,Sanyang Guo,Zhichao Yu,Wenfeng Wang,Kailiang Ren,Qiuming Peng,Shumin Han
The introduction of the heterogeneous catalysts with high activity can significantly improve hydrogen storage performance of MgH 2 , therefore, in this paper, we synthesize a carbon-supported transition metal compound, FeCoS@C derivative from ZIF-67, by utilizing the in situ formed C dispersive multiphase Mg 2 Co, α-Fe, Co 3 Fe 7 , and MgS to implement catalysis to MgH 2 . Noteworthily, MgH 2 -FeCoS@C rapidly absorbs 6.78 wt% H 2 within 60 s at 573 K and can also absorb 4.56 wt% H 2 in 900 s at 473 K. Besides, the addition of FeCoS@C results in decreasing of the initial dehydrogenation temperatures of MgH 2 from 620 to 550 K. The dehydrogenation activation energy of MgH 2 decreases from 160.7 to 91.9 kJ mol –1 . Studies show that the Mg 2 Co, α-Fe, and Co 3 Fe 7 act as “hydrogen channels” to accelerate hydrogen transfer due to the presence of transition metals, and MgS with excellent catalytic effect formed from MgH 2 -FeCoS@C provides a strong and stable catalytic effect. Besides, the carbon skeleton obtained by the carbonization of ZIF-67 not only serves as a dispersion for the multiphase catalytic system, but also provides more active sites for the catalysts. Our study shows that the multiphase and multiscale catalytic system provides an effective strategy for improving the hydrogen storage performance of MgH 2 .
研究领域:
材料科学
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催化
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2024
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IF 5.5
Shilong Wang,Chuqi Li,Ziyun Zhang,Lei Li,Wentao Ding,Sheng Han,Jibo Jiang
Engineering a heterogeneous structure with distinctive morphology and nanostructure is deemed to be an efficacious tactic for realising high energy density supercapacitors (SCs). Herein, the FeCo 2 S 4 @NiCo-LDH(FeCoS@NiCo-LDH)/NF nanocomposite heterostructure is successfully constructed through a facile two-step electrodeposition method. This heterostructure merges the merits of FeCoS with high electrical conductivity and NiCo-LDH with ultra-high specific surface area, which not only can deliver sufficient electroactive central sites, but also provide shorter routes for expedited ion diffusion, even more significantly, the heterogeneous interfaces that emerge in composites can moderate their electronic structure and augment electrical conductivity. Density functional theory (DFT) calculations indicate that the heterostructured FeCoS@NiCo-LDH/NF displays preferable electrochemical activeness and enhanced adsorption ability. Thanks to the abundance of heterogeneous interfaces and synergistic effects of the various active ingredients, FeCoS/NiCo-LDH electrodes exhibit an extraordinary specific capacity of 930 C g −1 at 1 A g −1 together with remarkable cycle longevity (10.9 % capacity decay after 10,000 cycles). In addition, a hybrid FeCoS@NiCo-LDH/NF//AC exhibits a high energy density of 52.81 Wh kg −1 at the 750 W kg −1 .
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2020
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IF 8.247
Yimin Yan,Yanping Hou,Zebin Yu,Lingli Tu,Shanming Qin,Guiyun Yuan,Danquan Lan,Shuo Chen,Jiangli Sun,Shuangfei Wang
The sluggish kinetics of cathodic oxygen reduction reaction (ORR) is one of the critical factors hindering the development of microbial fuel cells (MFCs). Herein, the metal organic framework (MOF)-derived Fe x Co 3-x S 4 /Fe y Co 9-y S 8 (FeCoS(MOF)) is in-situ grown on nickel foam as ORR catalyst with high doping of N and S. Results show that based on the role of FeCoMOF, the FeCoS(MOF) microspheres are made up of nanosheets piling-up without phase aggregation and structural collapse. Meanwhile, more defects are generated, resulting in low internal resistance, high quality activity and high turnover frequency . In the MFC with the FeCoS(MOF) cathode, the maximum power density is 2.55 times of that of Pt/C cathode. The excellent ORR activity is due to the unique morphology and rich oxygen defects, which shortens electronic transmission distance, facilitates the exposure of more active sites, and improves oxygen adsorption and conductivity. Moreover, the durability of FeCoS(MOF) cathode outperforms Pt/C cathode, with stable output voltage maintains for 2 months, while the Pt/C cathode decreases to 67% of the initial voltage. This work provides inspiration for developing efficient MOF-derived ORR catalyst.
研究领域:
材料科学
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环境科学
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能源科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Jianzhi Wang,Yuanhang Wu,Hongliang Yu,Congshu Hang,Wangshu Tang,Yijie Yang,Hongyi Chen,Hui Li,Faquan Yu
Developing efficient, low-cost and bifunctional catalysts with predominant durability for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) is an extraordinary challenge in the preparation of green hydrogen energy by electrochemical water splitting. Three-dimensional (3D) transition metal compounds have become a research hotspot as OER electrocatalysts , which can replace noble metal oxides such as RuO 2 and IrO 2 to reduce application costs. Herein, we synthesized a novel three-dimensional pine-tree-like bimetallic sulfide arrays on nickel foam (FeCoS/NF) using various optimization strategies such as morphology optimization, in situ growth and introduction of heterogeneous structures. The as-synthesized FeCoS/NF electrocatalyst only requires relatively low overpotential of 156 mV to achieve a current density of 20 mA cm −2 for OER, with a Tafel slope of only 37 mV dec −1 . It also has a small charge transfer resistance, an electrochemical surface area and good electrochemical stability in alkaline electrolytes . The excellent performance of FeCoS/NF can be attributed to the synergistic effect and amorphous phase of FeCoS as well as the well-defined pine-tree-like array architecture with a large surface area, abundant active sites, and sufficient gas and electrolyte diffusion channels.
研究领域:
材料科学
·
电化学
·
催化
·
能源材料
✓ 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）