JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·Vol. 107
·期 9
·6439-6455
·
IF 3.5
Liangliang Tang,Dongxu Yao,Yongfeng Xia,Jun Zhao,Ming Zhu,Yu-Ping Zeng
Complex liquid–solid reactions occur during brazing. A deep understanding of brazing liquid evolution is therefore of important concern for the bonding between filler and substrates. The joining of gas-pressure-sintered silicon nitride (Si 3 N 4 ) ceramic to oxygen-free copper (OFC) foil was prepared using Ag–Cu–TiH 2 filler at 875°C for 0.5 h. The effect of the Ag:Cu ratio on the interfacial microstructure and peeling strength of the joints was analyzed. The reaction of brazing liquid with Si 3 N 4 ceramic includes reactions with both the β-Si 3 N 4 and the grain boundary phases (Y–Si–Mg–O–N). The resulting interfacial reaction products include TiN, Ti 5 Si 3 , and potential Cu 3 Ti 3 O. Based on the phase composition and three-dimensional morphology of the interfacial reaction products in the Si 3 N 4 ceramic/OFC foil joints, a model for the evolution of the brazing liquid as the reaction proceeds was proposed. Peeling test results indicated that the peeling strength of the joints rises unilaterally with the increase of the Ag:Cu ratio in the filler until reaching the peak value of 24.3 N/mm at the maximum Ag:Cu ratio of 90:10. The mechanisms of the joint peeling fracture were discussed in detail.
研究领域:
材料科学
·
冶金学
·
陶瓷学
·
连接技术
·
表面工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Honghui Cheng,Yuan Chen,Wenpei Sun,Haoran Lou,Yanqi Liu,Qi Qi,Jiamin Zhang,Jingjing Liu,Kai Yan,Huiming Jin,Yao Zhang,Shuyi Yang
TiH 2 was introduced into the 4MgH 2 -NaAlH 4 composite by ball milling to improve the dehydrogenation and re-dehydrogenation performance of the composite. The non-isothermal dehydrogenation curve shows that the onset temperature of hydrogen release from 4MgH 2 -NaAlH 4 -TiH 2 is at around 100 °C, which is lower by 50 °C than that of 4MgH 2 -NaAlH 4 . The investigation by Kissinger's method indicates that 4MgH 2 -NaAlH 4 -TiH 2 possesses much lower activation energy (68 kJ mol −1 ) than 4MgH 2 -NaAlH 4 (159 kJ mol −1 ), indicating an enhanced dehydrogenation kinetics due to the additional TiH 2 . TiH 2 catalyzes the decomposition of MgH 2 and NaAlH 4 , respectively, and also the reaction between their products during the dehydrogenation process below 375 °C. At temperatures above 375 °C, TiH 2 will react with Mg 17 Al 12 to form Al 3 Ti and liberate contained hydrogen. TiH 2 also improved the isothermal hydrogenation kinetics of 4MgH 2 -NaAlH 4 desorbed system. The activation energy of re-hydrogenation for 4MgH 2 -NaAlH 4 -TiH 2 system was greatly reduced from 161.62 kJ mol −1 H 2 to 125.80 kJ mol −1 H 2 of 4MgH 2 -NaAlH 4 . The kinetics enhancement of hydrogen absorption is probably due to the intermediate phase Al 3 Ti, which is beneficial to the recombination of MgH 2 .
研究领域:
材料科学
·
氢气储存
·
固态化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhuanghe Ren,Xin Zhang,Zhenguo Huang,Jianjiang Hu,Yangzhong Li,Shiyou Zheng,Mingxia Gao,Hongge Pan,Yongfeng Liu
Nanosized titanium compounds are particularly effective in catalyzing hydrogen cycling by NaAlH 4 . Titanium hydride (TiH 2 ), as a catalyst, is highly interesting since it contributes hydrogen in addition to active Ti. However, it has been challenging to fabricate nanosized TiH 2 due to the strong affinity of Ti with oxygen. Herein, TiH 2 nanoflakes with a lateral size of ~10 nm and thickness of ~1 nm are successfully synthesized through a novel facile one-pot solvothermal process. In an anhydrous THF solution, LiH reacts with TiCl 4 rapidly at 100 °C forming TiH 2 and LiCl. The newly formed TiH 2 nucleates and grows epitaxially on the graphene surface due to the well-matched lattice parameters, giving rise to the formation of TiH 2 nanoflakes. Both theoretical calculations and experiments reveal the generation of Cl· radicals and unsaturated C C bonds when TiCl 4 reacts with THF, which promotes the formation of TiH 2 . The nanoflake-like TiH 2 on graphene enables an outstanding hydrogen storage performance of NaAlH 4 , i.e., full dehydrogenation at 80 °C and hydrogenation at 30 °C and under 100 bar H 2 , with a practical hydrogen capacity of 4.9 wt%, which has been never reported before.
研究领域:
材料科学
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纳米化学
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能源化学
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固态储氢
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催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2013
·Vol. 28
·期 5
·882-887
·
IF 0.484
Li Liang,Zhou Aiguo,Xu Lin,Li Zhengyang,Wang Libo
Titanium aluminum carbide (Ti 3 AlC 2 and Ti 2 AlC) powders were synthesized from TiH 2 powders instead of Ti powders as Ti source by a tube furnace under argon atmosphere without preliminary dehydrogenation. 95 wt% pure Ti 3 AlC 2 powders were synthesized from TiH 2 /1.1Al/2TiC at 1 450 °C for 120 min. High-purity Ti 2 AlC powders were also prepared from 3TiH 2 /1.5Al/C and 2TiH 2 /1.5Al/TiC powders at 1 400 °C for 120 min. The as-synthesized samples were porous and easy to be ground into powders. Sn or Si additives in starting materials increased the purity of synthesized Ti 3 AlC 2 obviously and expanded the temperature range for the synthesis of Ti 3 AlC 2 . With Si or Sn as additives, high pure Ti 3 AlC 2 was synthesized at 1 200 °C for 60 min from TiH 2 / x Si/Al/2TiC and TiH 2 / x Sn/Al/2TiC ( x = 0.1, 0.2), respectively.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2023
·
IF 5.4
Song Wu,Junli Wang,Xuanbing Wang,Di Jiang,Jinlong Wei,Xiaoning Tong,Zhenwei Liu,Qingxiang Kong,Naixuan Zong,Ruidong Xu,Linjing Yang
s Ti-based PbO 2 electrodes must currently address the high overpotential and low corrosiveness of the anodic oxygen evolution reaction (OER) during zinc electrowinning. In this study, a composite electrode composed of Ti/TiH 2 /β-PbO 2 − Mn 3 O 4 @C (0.6 g L –1 ) was fabricated using Ti/TiH 2 generated by electrochemical reduction of Ti/TiO 2 prepared by laser ablation as an intermediate layer, co-deposited β-PbO 2 , and Mn 3 O 4 @C micro-flakes prepared by high-temperature pyrolysis-oxidation as the active layer. In a zinc electrowinning test solution (50 g L –1 ZnSO 4 mixed with 150 g L –1 H 2 SO 4 ), the oxygen evolution and corrosion behavior of the obtained Ti/TiH 2 /β-PbO 2 − Mn 3 O 4 @C composite anodes were systematically investigated. Ti/TiH 2 /β-PbO 2 − Mn 3 O 4 @C (0.6 g L –1 ) exhibited a low overpotential of 493 mV, a low Tafel slope of 73.6 mV dec −1 , a low i corr of 2.320 × 10 −5 A cm −2 and voltage stability of 1.65 V vs. RHE for up to 72 h in stability tests, with an overall performance outperformed most of the reported Ti-based PbO 2 electrode materials. The outstanding catalytic activity is primarily attributable to the low resistance and porous interlayer of TiH 2 nanosheets, which speeds up the rate of electron transfer. The addition of Mn 3 O 4 @C micro-flakes to the active layer enhances the composite electrode's OER performance and corrosion resistance.
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2022
·
IF 5.767
Hua Fang,Peng Deng,Rui Liu,Kehua Han,Pengfei Zhu,Jianxin Nie,Xueyong Guo
Metal hydride has been used as a potential energetic material due to its high hydrogen storage density, high reactivity, high mass calorific value and large gas production. But it was still a great challenge towards optimizing and enhancing the energy-releasing properties of metal hydride. In this work, a novel molecular perovskite energetic material (H 2 dabco)[NH 4 (ClO 4 ) 3 ] (DAP-4) was introduced as a high energy oxidant to fabricate metal hydride (MH 2 , M=Mg, Ti, and Zr) based energetic composites. The thermal decomposition, ignition and combustion characteristics of MH 2 -based energetic composites were studied. The results showed that molecular perovskite energetic material DAP-4 was beneficial as oxidant in MH 2 -based high-energy solid composites, which were originated from its high energy properties and strong oxidation capacity. The ignition and combustion reaction mechanisms of MH 2 with DAP-4 as oxidant were provided. This work offered an effective way to realize energy-releasing performance of MH 2 by molecular perovskite energetic materials introduced for their potential application.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2026
·
IF 4.1
Xing Xiwei,Jin Shaohua,Chen Kun,Wang Junfeng
The thermal decomposition and metal-driving performance of four HMX/RDX-based PBXs with varying Al/TiH 2 ratios (0–8 mass% TiH 2 ) were investigated. While TiH 2 addition increased particle roughness, it altered the decomposition kinetics from a first-order model to a complex function described as (− ln(1 − α)) 2 . Although the onset decomposition temperature dropped notably, the critical Self-Accelerating Decomposition Temperature ( \({T}_\text{SADT}\) ) showed only a marginal reduction, suggesting that macroscopic thermal safety remains manageable. Cylinder tests revealed that within the investigated range, the 4 mass% TiH 2 formulation (RHTL-1) enhanced the wall velocity and Gurney coefficient by 5% and 3.6% during the early expansion phase (15–30 μs), whereas higher loadings (8 mass%) shifted energy release to later stages. Consequently, comparing the metallized formulations, 4 mass% TiH 2 offers the most favorable trade-off between early metal-drive capability and energy release characteristics.
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2023
·
IF 7.3
C. Jiang,X. Wang,X. Xiao,M. Piao,Y. Jia,J. He,L. Hu,Y. Zou,L. Sun,L. Chen
Chemical complex borohydride is a promising hydrogen storage material due to its large gravimetric and volumetric hydrogen capacities. However, the high dehydrogenation temperature and sluggish kinetics still place strong restrictions on its practical application in the hydrogen storage field. In this work, a synergetic approach of partial cation substitution and catalysis is developed to enhance the hydrogen storage properties of LiBH 4 . The Li/Mg based dual-cation borohydride (LiMg 2 (BH 4 ) 5 , LMBH) was successfully synthesized by wet chemical ball milling of LiBH 4 and MgCl 2 . The optimal (LMBH (4.5:1) sample, LiBH 4 and MgCl 2 in molar ratios of 4.5:1, possesses a maximum hydrogen desorption capacity (11.27 wt%) and the outstanding initial decomposition temperature (∼250 °C). Importantly, the LMBH (4.5:1) doped with TiF 3 shows a remarkable onset dehydrogenation temperature as low as 97.2 °C, which is about 190 °C lower than that of pristine LiBH 4 . The LMBH (4.5:1) doped with TiF 3 system releases 7.98 wt% H 2 within 170 min below 350 °C. And the dehydrogenation product of doped composite can reversibly absorb ∼4.72 wt% H 2 at a relatively moderate temperature of 280 °C, which is substantially lower than the reversible hydrogen absorption temperature of previous modified borohydride systems. Based on the structural characteristic analyses, the TiF 3 reacts with LMBH (4.5:1) to in-situ form actual catalytic components of TiB 2 and TiH 2 as the actual catalysts for LMBH (4.5:1), resulting in the improved hydrogen re/dehydrogenation properties. The synergetic modification of Li/Mg dual-cation substitution and TiB 2 /TiH 2 catalysis may lead to the development of light-metal borohydrides with outstanding hydrogen storage properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2022
·
IF 6.267
jialong Kang,Zhenyun Tian,Dapeng Zhong
The abundant metal Ti is a high-quality metal with lightweight, high strength, and corrosion resistance. However, due to its harsh preparation conditions, the price remains high, so titanium metal's simple and effective products have become a challenge for the world's scientific research community. In this paper, by calculating the oxygen potential of Ti–O, Ti–H, and Ti–H–O solid solutions, the oxygen potential of Ti–H–O was obtained when the oxygen content was 0.03 and 0.009. As H 2 enters the Ti–O lattice, the oxygen potential of the Ti–H–O system increases with the increase of H content. Thermodynamic calculations showed that introducing hydrogen effectively destroyed the stability of Ti–O solid solutions. At the same time, this paper uses a magnesiothermic as a reducing agent. To verify the feasibility of the above thermodynamics, reduce the spent V 2 O 5 –WO 3 /TiO 2 catalyst (Ti > 80 wt%) of titanium-rich materials in a hydrogen atmosphere. Finally, the spent V 2 O5–WO 3 /TiO 2 catalyst was reduced at 750 °C for 8–24 h to obtain TiH 2 powder with an oxygen content of 0.9 wt%.
研究领域:
材料科学
·
冶金工程
✓ 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）