INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
·
IF 8.1
Lingying Chen,Qinke Tang,Yichen Qi,Jiguang Zhang,Rui Shi,Yana Liu,Jun Wang,Yunfeng Zhu
Practical applications of magnesium hydride are hampered by high thermodynamic stability and slow kinetics. The design of highly active catalysts is essential to improve the kinetics of MgH 2 . Although studies concerned with the interaction between MgH 2 and catalyst have remained quite active, detailed investigation of the beneficial effect from the phase transformation is lacking. Herein, a high-activity VS 2 was designed and introduced to catalyze MgH 2 , and the MgH 2 -VS 2 system exhibited superior hydrogen desorption capabilities at comparatively low temperatures (3.5 wt% H 2 , 1800 s, 225 °C). This enhancement in the hydrogen storage performance of MgH 2 was attributed to the in-situ phase transformation of the catalytic species during hydrogen cycling. DFT calculations demonstrated the catalytic effect of VS 2 and in-situ formation of new species relative to MgH 2 . Our results provide a deeper insight into enhancing dehydrogenation mechanism on metal hydrides of the high-activity catalyst.
研究领域:
材料科学
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化学工程
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催化
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氢存储
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 9
·1838-1847
·
IF 5.773
Yi Zhang,Zhenyun Lan,Ni Jian,Zhuanghe Ren,Jianjiang Hu,Mingxia Gao,Hongge Pan,Yunhao Lu,Yongfeng Liu
In this work, we demonstrate a first attempt at understanding the catalytic mechanism of nanosized Co in reducing the dehydrogenation temperature of the Li–B–N–H hydrogen storage system by experimental observation and theoretical calculation. A nanosized Co@C composite (Co particles <10 nm) is successfully synthesized by casting a furfuryl alcohol-filled, Co-based metal–organic framework, MOF-74(Co), at 700 °C. Adding small quantities of the prepared nanosized Co@C composite significantly reduces the dehydrogenation temperature of the LiBH4–2LiNH2 system. The 5 wt% Co@C-containing sample releases approximately 10.0 wt% hydrogen at 130–230 °C with a peak temperature of 210 °C, which is reduced by 125 °C from that of the pristine sample. During hydrogen desorption, nanosized Co remains in the metallic state and only works as a catalyst to reduce the kinetic barriers of hydrogen release from the LiBH4–2LiNH2 system. Ab initio calculations reveal that the presence of a Co catalyst induces a redistribution of charge, which not only weakens the chemical H–B bonding but also enhances the electrostatic interactions between Hδ+ in the NH2 groups and Hδ− in the BH4 groups, consequently reducing the energy barriers for the formation of H2 molecules. This explains the low-temperature dehydrogenation behaviour of the Co-catalysed Li–B–N–H systems.
研究领域:
材料科学
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能源化学
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催化化学
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氢能源存储
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纳米技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 41
·期 39
·17462-17470
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IF 3.205
Bing Zhai,Xuezhang Xiao,Wenping Lin,Xu Huang,Xiulin Fan,Shouquan Li,Hongwei Ge,Qidong Wang,Lixin Chen
NbF 5 and eutectic 0.68LiBH 4 –0.32Ca(BH 4 ) 2 were successively infiltrated into highly ordered mesoporous carbon (CMK-3) to obtain a LiBH 4 –Ca(BH 4 ) 2 –NbF 5 @CMK-3 composite. A synergetic effect of nanoconfinement and catalysis on hydrogen desorption properties of the composite was achieved. The onset desorption temperature of LiBH 4 –Ca(BH 4 ) 2 –NbF 5 @CMK-3 is dramatically lower than 120 °C compared with that of as-milled LiBH 4 –Ca(BH 4 ) 2 or LiBH 4 –Ca(BH 4 ) 2 @CMK-3. A hydrogen amount as high as 13.3 wt% can be released within 250 min for LiBH 4 –Ca(BH 4 ) 2 –NbF 5 @CMK-3, compared with only 10.4 wt% for pure LiBH 4 –Ca(BH 4 ) 2 , in which nanoconfinement and catalysis both make some contribution. The cycling hydrogen desorption performance of the composite becomes better likewise due to the addition of NbF 5 . Further microstructure analysis reveals that F − tended to bind with Ca 2+ to form CaF 2 , whereas Nb compound is believed to catalyze the whole system in the form of Nb-based boride (NbB 2 ).
研究领域:
材料科学
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能源化学
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纳米科技
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储氢材料
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物理化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
Xiubo Xie,Ming Chen,Peng Liu,Jiaxiang Shang,Tong Liu
Nickel sulfides decorated reduced graphene oxide (rGO) has been produced by co-reducing Ni 2+ and graphene oxide (GO), and is subsequently ball milled with Mg nanoparticles (NPs) produced by hydrogen plasma metal reaction (HPMR). The nickel sulfides of about 800 nm completely in situ change to MgS, Mg 2 Ni and Ni multiple catalysts after first hydrogenation/dehydrogenation process at 673 K. The Mg-5wt%NiS/rGO nanocomposite shows the highest hydrogen desorption kinetics and capacity properties, and the catalytic effect order of the additives is NiS/rGO, NiS and rGO. At 573 K, the Mg-NiS/rGO nanocomposite can quickly desorb 3.7 wt% H 2 in 10 min and 4.5 wt% H 2 in 60 min. The apparent hydrogen absorption and desorption activation energies of the Mg-5wt%NiS/rGO nanocomposite are decreased to 44.47 and 63.02 kJ mol −1 , smaller than those of the Mg-5wt%rGO and Mg-5wt%NiS samples. The best hydrogen desorption properties of the Mg-5wt%NiS/rGO nanocomposite can be explained by the synergistic catalytic effects of the highly dispersed MgS, Mg 2 Ni and Ni catalysts on the rGO sheets, and the more nucleation sites between the catalysts, rGO sheets and Mg matrix.
研究领域:
材料科学
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纳米科技
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能源化学
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催化化学
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储氢材料
✓ 已验证
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-12
·
IF 17.694
Chen Zhigang,Xu Yafeng,Ding Ding,Song Ge,Gan Xingxing,Li Hao,Wei Wei,Chen Jian,Li Zhiyun,Gong Zhongmiao,Dong Xiaoming,Zhu Chengfeng,Yang Nana,Ma Jingyuan,Gao Rui,Luo Dan,Cong Shan,Wang Lu,Zhao Zhigang,Cui Yi
Tungsten carbides, featured by their Pt-like electronic structure, have long been advocated as potential replacements for the benchmark Pt-group catalysts in hydrogen evolution reaction. However, tungsten-carbide catalysts usually exhibit poor alkaline HER performance because of the sluggish hydrogen desorption behavior and possible corrosion problem of tungsten atoms by the produced hydroxyl intermediates. Herein, we report the synthesis of tungsten atomic clusters anchored on P-doped carbon materials via a thermal-migration strategy using tungsten single atoms as the parent material, which is evidenced to have the most favorable Pt-like electronic structure by in-situ variable-temperature near ambient pressure X-ray photoelectron spectroscopy measurements. Accordingly, tungsten atomic clusters show markedly enhanced alkaline HER activity with an ultralow overpotential of 53 mV at 10 mA/cm 2 and a Tafel slope as low as 38 mV/dec. These findings may provide a feasible route towards the rational design of atomic-cluster catalysts with high alkaline hydrogen evolution activity.
研究领域:
材料科学
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催化
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）