INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Senliang Xi,Xiaojun Wang,Kudzaishe Caren Tome,Tonghuan Zhang,Zongying Han,Meng Gao,Shixue Zhou,Hao Yu
In this work, NaBH 4 +2MgH 2 doped by ZrF 4 was prepared by the ball-milling method. The structure and the morphology of different systems were characterized by X-ray diffraction and scanning electron microscopy. The thermodynamic properties of hydrogen release were determined by temperature-programmed desorption and differential scanning calorimetry . Hydrogen desorption kinetic properties and hydrogen content were investigated by pressure composition isothermal method. The main objective of this work was to study the relationship between the heat of hydrogen release and the quantity of hydrogen released by In-situ calorimetry measurement. The NaBH 4 +2MgH 2 +0.1ZrF 4 can release about 7.4 wt.% H 2 by two steps. Firstly, the heat of hydrogen release of the first and the second steps were lower by 480.82 J·g −1 and 430.8 J·g −1 than that of NaBH 4 +2MgH 2 , respectively. And the dehydrogenation enthalpy of NaBH 4 +2MgH 2 went from −243.81 kJ·mol −1 to −191.2 kJ·mol −1 . Secondly, the addition of ZrF 4 can improve the hydrogen release kinetic property of NaBH 4 +2MgH 2 , which can release 5 wt.% H 2 in 2.5 h at 385 °C under 0.01 MPa hydrogen pressure. Therefore, NaBH 4 +2MgH 2 +0.1ZrF 4 will be a potential candidate as a fuel cell hydrogen supply system.
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
RSC Advances
·
2021
·Vol. 11
·期 39
·23846-23850
·
IF 3.361
Rongshan Lan,Yiyang Liu,Ling Han,Jing Yang,Huiqin Yin,Min Ge,Xiaobin Fu,Hongtao Liu,Yuan Qian
In this study, by applying 19F, 23Na and 7Li high-resolution NMR methods, the evolution of the [ZrxFy]4x−y local ionic structures in FLiNaK–ZrF4 salt mixtures were elucidated. K3ZrF7, Na3ZrF7 and Na7Zr6F31 crystal phases were identified when the melt salts were being solidified. The distribution of these [ZrxFy]4x−y species was dependent on the content of ZrF4 in FLiNaK eutectic salts. Moreover, K3ZrF7 phase transition from an orthorhombic lattice into a disordered cubic lattice was clarified, thereby causing dynamics of the coordinated F− ions to be reduced and the well-ordered crystal lattices to be destroyed. These mentioned results provide a further insight into the Zr–F based ionic structure and the formation of the disordered Zr–F structure in ZrF4-based eutectic salts.
研究领域:
材料科学
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核能工程
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Ming Lin,Yihong Liu,Jinzhao Guan,Yunliang Li,Mouhamadou Aziz Diop,Dianbao Feng,Yikun Ren,Yixiao Kang,Shifang Ma,Yujun Li,Fenghui An,Xianwei Hu
The KF-ZrF4 molten salt system has emerged as a promising candidate solvent for fourth-generation reactor designs, where its physicochemical characteristics are fundamentally governed by the ionic structure within the molten fluoride matrix. A variety of complex Zr–F ions, including ZrF5–, ZrF62–, ZrF73–, and ZrF84–, were identified in KF-ZrF4 molten salts with different molar ratios through Raman spectroscopy and quantum chemical calculations. Furthermore, the Zr2F9– ion with a bridging F structure was discovered in KF-ZrF4 molten salts with molar ratios of 1 and 0.65, and the experimental Raman spectrum of this ion was obtained. At higher KF to ZrF4 molar ratios of 5.7 and 2.3, ZrF73– and ZrF84– dominated, while ZrF5– and ZrF84– were predominant at molar ratios of 1 and 1.5. At a lower ratio of 0.67, ZrF5– emerged as the primary species. As the KF to ZrF4 molar ratio decreased, the system favored the formation of less-coordinated Zr–F ions. Moreover, a dynamic mutual transformation equilibrium existed among these complex ions, and this equilibrium was influenced by the zirconium fluoride content in the molten salt. Quantum electrochemical analysis revealed that ZrF5– was mainly involved in the cathode reaction. Zr4+ was first released from ZrF5–, gaining three electrons to form Zr+. Subsequently, Zr+ gained one electron, transforming into metallic zirconium at the cathode interface. These findings deepen our understanding of the physicochemical properties of molten salt reactors and have significant implications for advanced applications in metal purification, spent nuclear fuel recovery, and zirconium alloy production, thereby contributing to improved nuclear materials management and energy sustainability.
研究领域:
核材料科学
·
熔盐化学
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电化学
·
光谱学
·
量子化学
·
核能工程
✓ 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）