CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhe Zhang,Yusan Turap,Yongkang Wang,Yidi Wang,Zhentong Wang,Wei Wang
Thermochemical hydrogen storage technology based on iron-based materials has received significant attention owing to its low cost, safety features, and high volumetric hydrogen storage density. However, no consensus has been established on the optimal temperature range for hydrogen storage. This study investigated the impact of hydrogen storage temperature on hydrogen consumption capacity, hydrogen release capacity, and hydrogen storage energy consumption. The hydrogen storage temperature was optimized with the objectives of low energy consumption and high hydrogen storage density. The experiments were conducted using thermogravimetric analyzer and gram-scale packed-bed reactor setups, accompanied by thermodynamic and kinetic calculations. The research indicated that at 550 °C, the optimal hydrogen storage temperature, the lowest relative energy demand was 32.30 %, with the hydrogen consumption capacity reaching the theoretical maximum value of 4.8 %, and the hydrogen release capacity reaching 4.04 %. Furthermore, achieving the theoretical maximum value of hydrogen consumption capacity became exceedingly difficult when the hydrogen storage temperature exceeded 570 °C. Microstructural characterization and kinetic calculations revealed that this phenomenon was attributed to the formation of a dense iron layer on the particle surface, which impeded the solid-state diffusion of oxygen atoms. The formation of the intermediate phase wüstite was identified as the cause of the formation of the dense iron layer. Overall, this study provided theoretical support for iron-based thermochemical hydrogen storage processes and offered a perspective into the reaction behavior of the reduction of magnetite with hydrogen.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Changxu Li,Beibei Yan,Dahai Pan,Feng Yu,Xiaoliang Yan,Shuwei Chen,Binbin Fan,Ruifeng Li
Mesoporous alumina (MA) materials with outstanding textural properties have been synthesized by a facile approach, and were evaluated as supports of Pt-based catalyst for methylcyclohexane dehydrogenation . At 300 °C, the resultant catalyst demonstrates a much higher activity with a maximum hydrogen evolution rate of 2081 mmol/g Pt /min in comparison with the state-of-the-art alumina supported Pt catalysts. Interestingly, even after a long-time reaction of 100 h or regeneration, more than 80% of original activity was still maintained. The superior catalytic performance of the obtained catalyst is associated with the high specific surface area and large mesoporous size of support MA, thus benefiting the increase in the number of Pt active sites and efficiently inhibiting the formation of coke deposition during the reaction. Our contribution has provided a rational design strategy for highly efficient and stable dehydrogenation catalysts, which is a key for the utilization of methylcyclohexane-toluene system in hydrogen storage technology.
研究领域:
催化
·
材料科学
·
化学工程
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Yibo Qin,Longfei Chen,Meiying Dai,Yanfeng Zhu,Jiong Li,Wei Han,Wei Wei,Xinqing Chen
Hydrogen storage in liquid organic hydrogen carriers (LOHCs) is regarded as one of the most promising strategies and efficient hydrogen storage. However, the development of highly efficient dehydrogenation catalysts remains a significant challenge. This study investigated the synergistic effect of surface-bound hydroxyl (-OH) groups and palladium single-atom on mesoporous silica (MCM-41) catalyst in the dehydrogenation of dodecahydro-N-ethylcarbazole (12H-NEC). The optimized catalyst achieved complete dehydrogenation of 12H-NEC under low-temperature of 175 °C, demonstrating a dehydrogenation rate of 99.7 % (100 % conversion at 0.5 wt% Pd loading), while MCM-41 with fewer hydroxyl groups exhibited a much lower dehydrogenation rate of only 46 % under the same conditions. Systematic optimization of surface hydroxyl content enabled atomic-level dispersion of Pd, as confirmed by X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) analysis, which revealed stable Pd-O coordination structures without detectable Pd clusters. Kinetic studies demonstrate a stepwise dehydrogenation mechanism where the 4H-NEC dehydrogenation step constitutes the rate-determining process. Density functional theory (DFT) calculations further elucidate that Pd single atoms significantly reduce intermediate adsorption energies compared to metallic clusters, thereby accelerating hydrogen release. These findings provide critical insights for designing low-loading, single-atom catalysts optimized for efficient dehydrogenation applications.
研究领域:
催化
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能源存储
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材料科学
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表面化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2011
·Vol. 36
·期 14
·8203-8208
·
IF 4.057
Z.G. Zhang,H. Wang,M. Zhu
The major challenge of complex hydride for hydrogen storage is to release hydrogen at a moderate temperature with rapid kinetics. This paper reports a new composite system (NaBH 4 /ZnF 2 ) to generate hydrogen at a low temperature below 100 °C. The NaBH 4 and ZnF 2 mixture was prepared by a mechanical milling in a 2:1 M ratio. Dehydrogenation of the mixture during a heating process shows that the initial dehydrogenation temperature was below 100 °C with favorable kinetics. The structural analysis confirmed the formation of NaBF 4 and Zn in the reaction products. The study concerning the reaction mechanism reveals that ZnF 2 plays a role of reagent rather than catalyst. The produced intermediate of NaZnF 3 , however, affects the decomposition of the emitted B 2 H 6 . This work suggests that the extension of the decomposition mechanism of NaBH 4 /ZnF 2 composite system would favor the development of new catalysts for complex hydride systems.
研究领域:
材料科学
·
能源化学
·
无机化学
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储氢技术
·
纳米催化
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Sanyang Guo,Zhichao Yu,Yuan Li,Yaokun Fu,Zhuohan Zhang,Shumin Han
Magnesium hydride (MgH 2 ) is a promising hydrogen storage material with high weight and volume hydrogen capacity. However, higher operating temperature and reversible hydrogen capacity decay inhibit its wide application. To address these issues, Mg-Mg 2 Ni/C was obtained by ball milling magnesium and nickel-Metal Organic Framework (Ni-MOF), and following calcinations . Initial dehydrogenation temperature of the composite is 530 K, 70 K lower than that of MgH 2 , and the apparent activation energy of the composite is 77.6 ± 2.1 kJ/mol, which is only 50% of MgH 2 . At 423 K, the hydrogen capacity of the composite is about 6 wt% within 3600 s, and keeps unchanged after ten cycles. The carbon material introduced by Ni-MOF inhibits the agglomeration of Mg, and Mg 2 Ni/Mg 2 NiH 4 acts as a “hydrogen pump” in de/hydrogenation process. The carbon coating and “hydrogen pump” lead to the improvement of the ab/desorption kinetics and cycling stability. This attempt paves a potential way to achieve high performance Mg-based composite hydrogen storage materials.
研究领域:
材料科学
·
储氢技术
·
能源材料
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2020
·Vol. 49
·期 11
·3495-3502
·
IF 4.174
Yu Wang,Zhenmin Ding,Xinjun Li,Shuqin Ren,Shuhua Zhou,Hongming Zhang,Yuan Li,Shumin Han
Magnesium hydride is considered to be one of the most desirable hydrogen storage materials due to its high weight capacity (7.6 wt% H2) and low price. However, its relatively high operating temperatures and slow dynamics have always hampered its commercial applications. In this paper, nano-nickel particle coated nitrogen-doped carbon spheres (Ni@NCS) were synthesized by a chemical reduction method and then introduced into Mg to form an MgH2–Ni@NCS composite via hydriding combustion and subsequent high-energy ball milling processes. The results showed that the MgH2–Ni@NCS composite possessed high hydrogen storage capacity and fast absorbing/desorbing kinetics, absorbing 5.7 wt% H2 and desorbing 4.3 wt% H2 within 8 min at 623 K. Moreover, the capacity shows negligible degradation after 10 cycles, indicating that the MgH2–Ni@NCS composite has good cycling stability. Even at relatively low temperature (373 K), the MgH2–Ni@NCS composite still absorbed 4.2 wt% H2 within 60 min compared to 0.9 wt% H2 for milled MgH2. The improvement in hydrogen storage properties is ascribed to the in situ formed Mg2NiH4 induced dehydrogenation of MgH2 and effective prevention of the agglomeration of magnesium during the hydriding/dehydriding reaction by the carbon material.
研究领域:
材料科学
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能源化学
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纳米催化
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储氢技术
✓ 已验证
DOI
高影响因子
RARE METALS
·
2023
·Vol. 43
·期 3
·1153-1166
·
IF 8.8
Lu Li-Wen,Luo Hui,Li Guang-Xu,Li Yun,Wang Xin-Hua,Huang Cun-Ke,Lan Zhi-Qiang,Zhou Wen-Zheng,Guo Jin,Ismail Mohammad,Liu Hai-Zhen
The Li-Mg-B-H composite (2LiBH 4 + MgH 2 ) has a high capacity of 11.4 wt% as a hydrogen storage material. However, the slow kinetics and poor cycling stability severely restrict its practical applications. In this work, a layered Nb 2 C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the Li-Mg-B-H composite. The milled 2LiH + MgB 2 composites were initially hydrogenated to obtain the 2LiBH 4 + MgH 2 composites. The 2LiBH 4 + MgH 2 + 5 wt% Nb 2 C can release 9.0 wt% H 2 in 30 min at 400 °C, while it is only 2.7 wt% for the undoped 2LiBH 4 + MgH 2 . The dehydrogenation activation energies of MgH 2 and LiBH 4 are 123 and 154 kJ·mol −1 respectively for the 5 wt% Nb 2 C-doped composite, lower than the undoped composite (164 and 165 kJ·mol −1 ). The 2LiBH 4 + MgH 2 + 5 wt% Nb 2 C possesses excellent cycling stability, with the reversible capacity only slightly reduced from 9.4 wt% for the 1st cycle to 9.3 wt% for the 20th cycle. Nb 2 C keeps stable in the composite and acts as an efficient catalyst for the Li-Mg-B-H composite. It is believed that both the layered structure and the active Nb element contribute to the enhanced hydrogen storage performances of the Li-Mg-B-H composite. This work confirms that the Nb 2 C MXene with layered structure has a significant enhancing impact on the Li-Mg-B-H hydrogen storage materials, which is different from the bulk NbC. Graphical abstract
研究领域:
材料科学
·
能源化学
·
纳米催化
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储氢技术
·
固体化学
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2017
·
IF 4.636
Tianxin Li,Qian Li,Hongyu Long,Kuo-Chih Chou,Qun Luo
A modified Chou model with parameters of temperature ( T ), initial hydrogen pressure ( P 0 ), enthalpy change (Δ H ) and entropy change (Δ S ) is proposed in consideration of thermodynamic driving force. The meaningful activation energy E v can be calculated for the negative temperature dependence of hydriding reaction in hydrogen storage materials. This model is verified by the hydriding/dehydriding experimental data of (LaNi 5 ) 1− x Mg x ( x = 0, 0.018, 0.041, 0.063). The calculated results indicate that the hydriding kinetics of (LaNi 5 ) 1− x Mg x alloys are controlled by diffusion of hydrogen atom in hydride. The addition of small amount of magnesium improves the kinetic performance of LaNi 5 slightly. Furthermore, the modified Chou model was compared with the previous model that successfully explain the negative temperature depending hydrogenation reaction of Mg-based alloys. The fitting results show that the modified Chou model can describe the hydrogen absorption kinetic mechanism of negative temperature dependent materials more accurately.
研究领域:
材料科学
·
能源化学
·
物理化学
·
合金设计
·
储氢技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）