Energetic Materials Frontiers
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2023
·
IF 0
Zheng-hang Luo,Jia-jun Zhou,Hao Li,Yuan-hua Xia,Liang-fei Bai,Hai-jun Yang
The deuteration of energetic materials contributes to high signal-to-noise ratios (SNRs) in neutron diffraction, thus allowing the structures of energetic materials to be effectively investigated. This study developed the synthesis methods of deuterated energetic materials through chemical synthesis or newly developed one-pot H/D exchange. Using these methods, it synthesized nine deuterated energetic materials in a concise and low-cost manner: deuterated 1,3,5-triamino-2,4,6-trinitrobenzene (TATB- d 6 , 1 ), 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX- d 8 , 2 ), 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX- d 6 , 3 ), dihydroxylammonium 5,5′-bis(tetrazole-1-oate) (TKX-50- d 8 , 4 ), nitroguanidine (NQ- d 4 , 5 ), 1,1-diamino-2,2-dinitroethylene (FOX-7- d 4 , 6 ), 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105- d 4 , 7 ), trinitrotoluene (TNT- d 3 , 8 ), and 3-nitro-1,2,4-triazol-5-one (NTO- d 2 , 9 ). Furthermore, the single crystals of HMX- d 8 ( 2 ) and RDX- d 6 ( 3 ) were obtained, and the α- , β- , γ- , and δ- polymorphs of HMX- d 8 ( 2 ) were prepared accordingly. The deuterated energetic materials were characterized and analyzed using infrared spectroscopy (IR), nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetry (TG), X-ray diffraction (XRD), and neutron diffraction. Besides, this study determined the decomposition activation energy ( E a ), pre-exponential factor (A), decomposition rate constant ( k ), and critical explosion temperature ( T b ) of TATB- d 6 ( 1 ), HMX- d 8 ( 2 ), and RDX- d 6 ( 3 ) via DSC experiments at different heating rates. The NMR and neutron diffraction data show that these deuterated energetic materials have high deuteration rates of more than 95%. The DSC and TG analyses indicate that the deuterated energetic materials exhibit slightly higher decomposition temperatures than their nondeuterated counterparts. Furthermore, neutron diffraction shows that the deuterated energetic materials feature high SNRs.
研究领域:
化学
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材料科学
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物理学
✓ 已验证
DOI
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 21
·7143-7151
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IF 4
Lu Liang,Xiaohui Li,Xiaoge Wang,Zhaoji Luo,Kun Lin,Qiang Li,Sihao Deng,Lunhua He,Xiaojun Kuang,Xianran Xing
Mixed electronic and oxide ionic conduction was enabled in digermanate-type La2−xCaxGe2O7−x/2 containing Ge3O10 chains and isolated GeO4 units by substitution of La3+ with Ca2+. The structure and solid solution limit of Ca doped La2Ge2O7 were studied by systematic experiments, including rotation electron diffraction (RED), X-ray diffraction (XRD) and neutron powder diffraction (NPD) experiments, etc. The preferred occupation of Ca2+ and oxygen vacancies was investigated by Rietveld analysis of the NPD data. The obtained conducting material La1.925Ca0.075Ge2O6.963 exhibits superior thermal stability and an order of magnitude improvement in conductivity compared to the parent La2Ge2O7 (∼9 × 10−5 S cm−1 at 1000 °C). BVEL calculations reveal that the oxygen vacancies were stabilized and transported within the framework of La2Ge2O7 by sharing oxygen and oxygen exchange between the adjacent Ge3O10 chains and GeO4 units, exhibiting a three-dimensional oxide ion transport nature.
研究领域:
无机化学
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固态离子学
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功能材料
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结构化学
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能源材料
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晶体化学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Wenzhuo Chen,Jian Yang,Jiazheng Hao,Feiran Shen,Lunhua He,Xia Deng,Jiasheng Lv,Jing Fang,Laijun Liu,Jungu Xu
The undoped K2ZnV2O7 material has a melilite-like structure, with the K+ ions distributed orderly on two distinguishable crystallographic sites, which is the main difference with the case in a typical A2B3O7 melilite material where the A site cations occupy only one crystallographic position. Herein, we report that substitution of Ga for Zn in K2ZnV2O7 would induce the K+ ions’ order-to-disorder transition and transform the K2ZnV2O7 from the melilite-like structure to a typical melilite phase, coupled with significantly enhanced oxide ion conductivity, e.g. ∼1.01 × 10–1 S/cm at 600 °C for the K2Zn0.7Ga0.3V2O7.15 sample, which is about 2 orders of magnitude higher than the parent material. The powder neutron diffraction data analysis results revealed two sites for the interstitial oxygen defects that are introduced by the donor-doping. The introduction of interstitial oxygen into the K layer strongly correlated with the K ions’ order-to-disorder transition, while the interstitial oxygens within the 5-fold (Zn/Ga/V)O4 tetrahedral rings are responsible for the enhanced oxide ion conductivity. These findings provided a comprehensive understanding of the melilite-like and typical melilite materials for the mechanism of the stabilization and migration of interstitial oxygen defects.
研究领域:
材料科学
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固体化学
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电化学
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晶体学
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无机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2021
·Vol. 9
·期 25
·14534-14544
·
IF 12.732
Fei Shen,Zhongti Sun,Liang Zhao,Yuanhua Xia,Yanyan Shao,Jingsheng Cai,Shuo Li,Chen Lu,Xiaoling Tong,Yu Zhao,Jingyu Sun,Yuanlong Shao
Developing high energy density and high-power density electrode materials is of great importance for lithium-ion batteries to satisfy the requirements of the customer market. We report that introducing Mo into Nb2O5 at a low temperature leads to phase transition from bronze-phase T to crystallographic shear-phase H. The resulting Nb1Mo0.1O2.8 exhibits higher energy density than T-Nb2O5 and improved rate-performance and cycling-stability compared to H-Nb2O5. Neutron diffraction was applied to Nb1Mo0.1O2.8 to characterize the structure and two-phase ratios of the mixed metal oxide together with the first-principles method to calculate the possible Mo substitution sites. The Nb1Mo0.1O2.8 anode displays intrinsic pseudocapacitive lithium-ion intercalation with a high energy density of 362 mA h g−1 at 0.2C. In situ XRD results suggest that Nb1Mo0.1O2.8 is able to intercalate more lithium ions with smaller structure expansion compared with H-Nb2O5; furthermore, a computational method reveals that the introduction of Mo into the oxide increases Li atom adsorption energies and decreases the diffusion barrier. Therefore, Nb1Mo0.1O2.8 is a promising anode material for high-capacity and high-rate lithium-ion energy storage.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·Vol. 35
·期 20
·2420971
·
IF 19
Ruihua Zhou,Ajay Gautam,Emmanuelle Suard,Shenghao Li,Swapna Ganapathy,Kai Chen,Xin Zhang,Ce-Wen Nan,Shuo Wang,Marnix Wagemaker
Lithium argyrodite thiophosphate superionic conductors are being explored as promising solid electrolytes for all-solid-state batteries, primarily due to their high ionic conductivity and ease of processing. Yet, these electrolytes present challenges such as chemical instability in humid conditions and incompatibility with cathode materials. Although some lithium argyrodites show improved air stability, their ionic conductivity deteriorates below the practically required value. Herein, based on hard soft acid base theory, a new family of lithium argyrodite, as solid solution Li 6−x AsS 5−x Br 1+x (for 0.0 ≤ x ≤ 0.6), has been proposed to address these issues. Through a combination of neutron diffraction, NMR spectroscopy, and electrochemical impedance spectroscopy, it has been determined that the partial substitution of S 2− by Br − weakens interactions within the Li + “cage”, facilitating long lithium-ion movement throughout the structure. An additional T4 Li + site is identified, offering a lower energy barrier for inter-cage jumps. Consequently, the Li 5.5 AsS 4.5 Br 1.5 member of the composition series exhibits a higher Li-ion diffusivity resulting in a remarkable ionic conductivity of 15.4 mS cm −1 . Compared with lithium thiophosphates, the Li 5.5 AsS 4.5 Br 1.5 also shows excellent air stability. This research opens a new avenue for developing air-stable sulfide solid electrolytes with high ionic conductivity necessitated for practical application in solid-state batteries.
研究领域:
材料科学
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固体离子学
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储能
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电池技术
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无机化学
✓ 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）