JOURNAL OF MATERIALS RESEARCH
·
2015
·Vol. 30
·期 7
·967-972
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IF 1.647
Tan Yajun,Zhu Yunfeng,Yuan Jianguang,Li Liquan
Ti was added to Mg–Ni alloy (Mg 95 Ni 5 ) by a novel hydriding combustion synthesis (HCS) process. The effect of Ti on hydrogen absorption/desorption kinetics of Mg 95 Ni 5 was investigated. The results showed that Ti had superior catalytic effects on hydrogen storage properties of Mg 95 Ni 5 , which required only 80 s to reach its saturated hydrogen absorption capacity of 6.29 wt% at 473 K and released 5.49 wt% hydrogen within 900 s at 553 K. Based on an Arrhenius analysis, the activation energy of the hydrogen desorption process was 80.8 kJ mol −1 for the main phase of MgH 2 in the Ti-doped Mg 95 Ni 5 . The excellent hydriding/dehydriding properties were related to the existence of TiH 1.924 , which improved the efficiency of mechanical milling and was helpful in the refinement of the crystallite size of MgH 2 , resulting in more fresh surface area and grain boundary area. Besides, it was thought to restrain the Mg particles from growth during the hydrogenation/dehydrogenation cycles.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Xiaolu Fan,Yao Zhang,Yunfeng Zhu,Cassandra Phillips,Xinli Guo,Jian Chen,Zengmei Wang,Liquan Li
Mixed alkali alanates Li x Na 3-x AlH 6 have been successfully synthesized by means of grinding mixtures of Li 3 AlH 6 and Na 3 AlH 6 in specific molar ratios. Non-stoichiometric Li x Na 3-x AlH 6 compounds with single perovskite-type structures (space group Fm-3m) can be formed only within the composition range of x = 0.9–1.3. Li 1.3 Na 1.7 AlH 6 exhibits superior hydrogen storage properties over other Li x Na 3-x AlH 6 compounds. Its onset dehydrogenation temperature (∼423 K) was lowered by more than 40 K from other samples in temperature programmed dehydrogenation (TPD) curves. Also, the dehydrogenation capacity of Li 1.3 Na 1.7 AlH 6 (3.45 wt.%) is the highest among the compounds. The dehydrogenation enthalpy values of Li x Na 3-x AlH 6 decreased as x increased from 0.9 to 1.3 according to the results by isothermal pressure-composition (PCI) curves and van't Hoff plots. It shows that the dehydrogenation Li 1.3 Na 1.7 AlH 6 (49.7 kJ mol H 2 −1 ) was greatly destabilized from that of LiNa 2 AlH 6 (68.1 kJ mol H 2 −1 ). Furthermore, the apparent activation energy of dehydrogenation for Li 1.3 Na 1.7 AlH 6 (138.1 kJ mol −1 ) was remarkably lowered from that of LiNa 2 AlH 6 . This illustrates that Li 1.3 Na 1.7 AlH 6 exhibits enhanced dehydrogenation kinetics from that of LiNa 2 AlH 6 .
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2021
·
IF 2.917
Yan CHEN,Hao-yu ZHANG,Fu-ying WU,Ze SUN,Jia-guang ZHENG,Liu-ting ZHANG,Li-xin CHEN
Mn nanoparticles (nano-Mn) were successfully synthesized and doped into MgH 2 to improve its de/hydrogenation properties. Compared with MgH 2 , the onset desorption temperature of 10 wt.% nano-Mn modified MgH 2 was decreased to 175 °C and 6.7, 6.5 and 6.1 wt.% hydrogen could be released within 5, 10 and 25 min at 300, 275 and 250 °C, respectively. Besides, the composite started to take up hydrogen at room temperature and absorbed 2.0 wt.% hydrogen within 30 min at low temperature of 50 °C. The hydrogenation activation energy of MgH 2 was reduced from (72.5±2.7) to (18.8±0.2) kJ/mol after doping with 10 wt.% nano-Mn. In addition, the MgH 2 + 10 wt.% nano-Mn composite exhibited superior cyclic property, maintaining 92% initial capacity after 20 cycles.
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
Darvaish Khan,Jianxin Zou,Mingguang Pan,Zhewen Ma,Wen Zhu,Tianping Huang,Xiaoqin Zeng,Wenjiang Ding
In this study, MgH 2 and Co powders were mechanically milled in the molar ratio 2:1 and compressed to hard-packed cylindrical pellets. The microstructure, phase changes, and hydrogen storage properties of the mechanically milled 2MgH 2 Co powder and the 2MgH 2 Co compressed pellet were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and synchronous thermal (DSC/TG) analyses. Dehydrogenation of the 2MgH 2 Co compressed pellet is mainly due to the decomposition of Mg 2 CoH 5 while it is the dehydriding of MgH 2 for the milled 2MgH 2 Co powder. Pressure composition absorption isotherms of the 2MgH 2 Co powder and 2MgH 2 Co compressed pellet show two and three plateaus, respectively, corresponding to the formation of Mg 6 Co 2 H 11 and Mg 2 CoH 5 hydride phases . For the compressed 2MgH 2 Co pellet, enthalpies of formation/decomposition were measured to be −58.11±7.69 kJ/mol H 2 /55.70±3.34 kJ/mol H 2 for Mg 2 CoH 5 and -81.89±10.39 kJ/mol H 2 /74.47±5.27 kJ/mol H 2 for Mg 6 Co 2 H 11 . In contrast, hydrogenation/dehydrogenation enthalpies of Mg 2 CoH 5 and Mg 6 Co 2 H 11 mechanically milled 2MgH 2 Co powder were −73.98±10.1 kJ/mol H 2 /71.67±1.38 kJ/mol H 2 and -96.86±8.73 kJ/mol H 2 /89.95±10.81 kJ/mol H 2 , respectively. Fast hydrogenation was observed in the dehydrided 2MgH 2 Co compressed pellet with about 2.75 wt% absorbed in less than 1 min at 300 °C and a maximum hydrogen storage capacity of 4.43 wt% (2.32 wt% for the 2MgH 2 Co powder) was achieved. The hydrogen absorption activation energy of the 2MgH 2 Co compressed pellet (64.34 kJ-mol −1 H 2 ) is lower than the mechanically milled 2MgH 2 Co powder (73.74 kJ-mol −1 H 2 ). The results show that mechanical milling followed by high-pressure compression is an efficient method for the synthesis of Mg-based complex hydrides with superior hydrogen sorption properties .
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
Materials Today Communications
·
2022
·
IF 3.662
Yingjun Li,Yakun Guo,Zekun Jing,Xingtao Zhao,Yuanlin Zhou,Maobing Shuai
To solve the problems of hydrogen embrittlement and explosion risk generated by the use of hydrogen energy in large-scale applications, organic hydrogen getters have been used to eliminate hydrogen in sealed systems and related fields. However, the hydrogen absorption rate of existing hydrogen getters needs to be further improved. Herein, a three-dimensional (3D) N-doped carbon with interconnected hierarchical pores loaded with a uniform dispersion of palladium particles (6.8 nm) was successfully developed. This material was used as a catalyst for 1,4-bis(phenylethynyl)benzene (DEB) hydrogenation under mild conditions, exhibiting good catalytic performance. The hydrogen uptake performance of this Pd/MFC/DEB getter for the reduction of hydrogen gas was examined at 0 – 1 bar and 25 ℃ with hydrogen consumption evaluated with time. The prepared Pd/MFC/DEB getter demonstrated a hydrogen uptake of 212.2 cm 3 /g after about 20 h, which was significantly higher than that of a typical Pd/AC/DEB pallet getter (162.0 cm 3 /g). This was due to the interactions between the Pd and MFC support, which enhanced the dispersion of Pd, increased the area available for the reaction with DEB, promoted the hydrogen dissociation process, and improved the hydrogen spillover effect. This research offers a highly promising approach for the use of MFC as a catalyst support material in hydrogen getters.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2018
·
IF 0
Zhongliang Ma,Jiguang Zhang,Yunfeng Zhu,Huaijun Lin,Yana Liu,Yao Zhang,Delong Zhu,Liquan Li
Metal nanocatalysis is an effective method to enhance the hydrogen storage properties of magnesium hydride (MgH2), and the catalytic effect can be further improved by a matrix material supported nanometal. In this work, carbon supported nano-Ni (Ni@C) was synthesized by calcination of dimethylglyoxime dinickel chelate, and then it was doped into MgH2 to improve the de/rehydrogenation kinetics. This shows that the homogeneously distributed Ni with refined particle size in carbon base leads to superior catalytic effects on hydrogen absorption/desorption of MgH2-5 wt % Ni@C. The MgH2-5 wt % Ni@C starts to desorb hydrogen at 187 °C, which is 113 °C lower than that of as-milled MgH2. Moreover, it takes only 500 s to thoroughly desorb hydrogen at 300 °C, which is 3000 s faster than as-milled MgH2 under the same dehydrogenation conditions. According to the Kissinger’s method, the apparent activation energy for desorption of the MgH2-5 wt % Ni@C is 66.5 ± 1.8 kJ mol–1, which is about 79.9 kJ mol–1 lower than that of as-milled MgH2. Cycling experiments show that the capacity retentions of hydrogen absorption and desorption after 10 cycles at 275 °C are 91% and 93%, respectively. Transmission electron microscope analysis shows that part of Ni transformed to Mg2NiH4/Mg2Ni during hydrogen absorption/desorption cycles.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
RSC Advances
·
2013
·Vol. 4
·期 6
·3082-3089
·
IF 2.562
Weitong Cai,Hui Wang,Dalin Sun,Qingan Zhang,Xiangdong Yao,Min Zhu
Destabilization by the alkali metal hydroxides LiOH, NaOH, and KOH in the solid-state dehydrogenation of LiBH4 is reported. 6.5 wt% of hydrogen was liberated within 10 minutes at 250 °C. Destabilization originated from the interaction between H+ in [OH]− and H− in [BH4]−. A larger Pauling's electronegativity of the alkali metal (Li > Na > K) led to a greater acidity of the proton donor [OH]− site, and thus enhanced destabilization. The temperature of the predominant dehydrogenation was reduced to 207, 221, and 230 °C, for ball milled LiBH4–LiOH, 2LiBH4–NaOH, and 2LiBH4–KOH, respectively. The LiBH4: LiOH stoichiometry greatly affected the destabilization, by providing differing reaction pathways in LiBH4-xLiOH (x = 1, 1.36, 4). The incremental increase in the LiOH content of LiBH4-xLiOH increased the dehydrogenation rate, but the temperature increased from 207 °C (x = 1) to 250 °C (x = 4). 4.1 and 6.5 wt% of hydrogen was liberated within 10 minutes by LiBH4–LiOH and LiBH4–4LiOH, respectively. The incremental increase in dehydrogenation temperature was attributed to differing [BH4]−⋯[OH]− interactions, formed by the differing stoichiometric ratios.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Linsen Li,Xiang Gong,Zhuwei Yang,Riguang Zhang,Zhao Jiang,Tao Fang
As the candidates for large-scale hydrogen storage , liquid organic hydrogen carriers (LOHCs) exhibit evident advantages in hydrogen storage density and convenience of storage and transportation. Among them, NECZ (N-ethylcarbazole)/12H-NECZ (dodecahydro-N-ethylcarbazole) is considered as a typical system with the lower hydrogenation/dehydrogenation temperature. However, the low dehydrogenation efficiency restrict its commercial applications. In this work, the single-layer Ti 3 C 2 T x MXene was employed as the support to load the Pt nanoparticles for the 12H-NECZ dehydrogenation reaction. The effect of transition metals , loading amounts and morphologies of catalysts were analyzed. It was found that the 3 wt% Pt/S–Ti 3 C 2 T x catalyst exhibited the best catalytic performance with 100% conversion, 91.55% selectivity of NECZ and 5.62 wt% hydrogen release amount at 453 K, 101.325 kPa for 7 h. The product distributions and kinetics analysis suggested that the elementary reaction from 4H-NECZ to NECZ was the rate-limiting step. The selectivity of NECZ is sensitive to the dehydrogenation temperature. Combined with the XRD , SEM , HRTEM , XPS , BET and FT-IR results, it could be indicated that the special two-dimension structure of S–Ti 3 C 2 T x and electronic effect between Pt and S–Ti 3 C 2 T x enhanced the dehydrogenation efficiency of 12H-NECZ. The measurements of cyclic dehydrogenation indicated that the Pt/S–Ti 3 C 2 T x catalyst exhibited good stability after 42 h. This work brought a new strategy for the design of efficient catalysts using two-dimensional materials in the applications of the liquid organic storage hydrogen technology .
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xin Zhang,Yukai Lin,Lingchao Zhang,Zhenguo Huang,Limei Yang,Zhenglong Li,Yaxiong Yang,Mingxia Gao,Wenping Sun,Hongge Pan,Yongfeng Liu
Sodium alanate, NaAlH 4 , has great potential as a hydrogen carrier but suffers from sluggish kinetics and poor reversibility caused by high energy barriers. Transition metal-based catalysts are especially effective in reducing kinetic energy barriers for hydrogen cycling of NaAlH 4 . Herein, we demonstrate a facile fabrication of TiC nanoparticles with 2–4 nm in size supported on carbon (nano-TiC@C). The resultant product consists of approximately 49.2 wt% of TiC and 50.8 wt% of C, and exhibits high and stable catalytic activity for hydrogen storage process of NaAlH 4 . The 7 wt% nano-TiC@C-containing NaAlH 4 releases 5 wt% H 2 starting from 65 °C and reabsorbs all released hydrogen at 30 °C under 100 bar H 2 , outperforming NaAlH 4 modified by commercial TiC nanoparticles (∼50 nm in size). The enhancement is related to the ultrasmall size and high reactive activity of as-synthesized TiC nanoparticles. Moreover, the weak electronegativity of C prevents the formation of Na-based by-products, which are often observed in oxide and halide-containing systems. This finding sheds light on how to design and synthesize high-performance catalytic additives for light-metal hydride-based hydrogen storage materials.
研究领域:
材料科学
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氢能技术
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Hu Liu,Jingwen Xue,Pengfei Yu,Yankang Zhang,Jinhua Wang,Defu Che
Hydrogen is a clean secondary energy as well as an efficient energy carrier, but the low density and small molecular hydrogen result in high economic and energetic efforts to store and transport hydrogen. In addition, the hydrogen produced by the current industry is usually impure and requires gas separation, which consequently increases the cost of hydrogen. A promising hydrogen storage technology using liquid organic hydrogen carrier (LOHC) can permit the safe storage of hydrogen for long time through the reversible chemical reaction in the presence of catalyst. The selective hydrogenation reaction of N -ethylcarbazole (NEC), an attractive LOHC compound due to the low dehydrogenation temperature of perhydro- N -ethylcarbazole (12H-NEC), with hydrogen was conducted in this study to achieve both separation and hydrogen storage for hydrogen-rich raw gas from natural gas steam reforming. First, hydrogenation experiments of molten NEC under a pure hydrogen atmosphere were carried out to determine the suitable hydrogenation conditions and reaction pathways. Then, the effect of methane addition on NEC hydrogenation was analyzed. Results indicate that there are multiple parallel pathways in the hydrogenation of NEC. The reaction rate from 8H-NEC to 12H-NEC step is extremely slow and this step is unstable at 453 K. The optimal hydrogenation temperature of NEC is 443 K and the apparent activation energy is 67.6 kJ·mol −1 . The addition of methane reduces the initial reaction rate from 0.877 g H2 ·(g Ru ·min) −1 to 0.640 g H2 ·(g Ru ·min) −1 but increases the maximum degree of hydrogenation ( DoH ) from 0.870 to 0.909.
研究领域:
化学工程
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能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Juan Du,Tianfeng Cai,Qiao Han,Hongda Wu,Qing Zhao,Lufan Zheng,Shuo Liu,Zhanxu Yang
The hydrogen spillover is considered a powerful strategy for improving the kinetics of hydrogen evolution reaction (HER) due to the decoupling of hydrogen adsorption and desorption. However, the hydrogen spillover rate strongly depends on the metal-support interfaces, and the Fermi levels (E f ) difference between metal and support hinders the occurrence of hydrogen spillover. Here, we prepared platinum (Pt) doped on molybdenum disulfide (MoS 2 ) with sulfur vacancies (Sv) catalyst (Pt/Sv-MoS 2 ) and investigated the internal relationship between metal-support interfaces and hydrogen spillover mechanism. The experimental and theoretical results show that sulfur (S) vacancies reduce the work function (ΔΦ) at the metal-support interface, thus accelerating the migration rate of hydrogen from Pt to Sv-MoS 2 . Meanwhile, the introduction of S vacancies promotes the high dispersion of Pt nanoparticles (Pt NPs) and weakens the electron supply from Pt to MoS 2 , facilitating active hydrogen (*H) adsorption step and thus increasing the hydrogen coverage on the Pt sites. Consequently, the prepared Pt/Sv-MoS 2 catalyst exhibited significantly enhanced HER activity, achieving an overpotential of 26 mV at 10 mA·cm −2 and a Tafel slope of only 28 mV·dec −1 , which is superior to commercial 20 % Pt/C.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Haiguang Gao,Rui Shi,Yuting Shao,Yana Liu,Yunfeng Zhu,Jiguang Zhang,Liquan Li
Herein, a novel flower-like Ni MOF with good thermostability is introduced into MgH 2 for the first time, and which demonstrates excellent catalytic activity on improving hydrogen storage performance of MgH 2 . The peak dehydrogenation temperature of MgH 2 -5 wt.% Ni MOF is 78 °C lower than that of pure MgH 2 . Besides, MgH 2 -5 wt.% Ni MOF shows faster de/hydrogenation kinetics, releasing 6.4 wt% hydrogen at 300 °C within 600 s and restoring about 5.7 wt% hydrogen at 150 °C after dehydrogenation. The apparent activation energy for de/hydrogenation reactions are calculated to be 107.8 and 42.8 kJ/mol H 2 respectively, which are much lower than that of MgH 2 doped with other MOFs. In addition, the catalytic mechanism of flower-like Ni MOF is investigated in depth, through XRD , XPS and TEM methods. The high catalytic activity of flower-like Ni MOF can be attributed to the combining effect of in-situ generated Mg 2 Ni/Mg 2 NiH 4 , MgO nanoparticles , amorphous C and remaining layered Ni MOF. This research extends the knowledge of elaborating efficient catalysts via MOFs in hydrogen storage materials.
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
危险品化学品经营许可证（带存储）