INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Zhongxuan Lin,Zhenluo Yuan,Huanhuan Zhang,Shuyan Guan,Xiaojiao Wang,Shiqian Zhao,Guangxin Fan,Yanping Fan,Baozhong Liu
Lowering the dehydrogenation temperature and maintaining high dehydrogenation capacity are greatly hindering the practical application of α-AlH 3 for the hydrogen fuel cell industry. Herein, the layered accordion-like V 2 C MXene is synthesized and doped into α-AlH 3 by mild ball milling . The 1 wt.% V 2 C-catalyzed α-AlH 3 possesses excellent dehydrogenation performance with a low initial decomposition temperature of 70.5 °C and a high hydrogen release capacity of 8.1 wt.%. Furthermore, 7.8 wt.% of hydrogen could be quickly released from α-AlH 3 -1 wt.% V 2 C composite within 15 min at 120 °C, with a lower activation energy of 69.5 kJ/mol than that of as-received sample. The excellent dehydrogenation performance is attributed to the high activity of the zero valence V catalyst which is transformed from the multivalent V during ball milling and to promote dissociation and reorganization of hydrogen. This effective approach significantly enhances the dehydrogenation of α-AlH 3 , providing a hopeful approach for modifying metal hydrides .
研究领域:
材料科学
·
无机化学
·
能源化学
·
纳米材料
·
储氢材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2021
·
IF 8.067
Fengnian Zhang,Fuhao Cheng,Chufei Cheng,Meng Guo,Yufeng Liu,Yang Miao,Feng Gao,Xiaomin Wang
Abatract A series of compositionally complex fluorite oxides (CCFOs) were prepared by ball milling the mixture of ZrO 2 , HfO 2 , Y 2 O 3 , La 2 O 3 , and Pr 6 O 11 followed by conventional solid-state sintering. Both XRD and TG-DSC results demonstrated that single-phase (Zr 0.2 Hf 0.2 Pr 0.2 Y 0.2 La 0.2 )O 2-δ was formed at 1400 °C. Elements in bulk ceramic were uniformly distributed without evident accumulation according to SEM-EDS pictures. TEM results revealed that polycrystalline ceramic powder was assignable to cubic Fm-3m fluorite structure. The electrical conductivity ( σ ) was measured via EIS technology and activation energy ( E a ) of CCFOs was calculated in Arrhenius plots. In the temperature range of 300-750 °C, CCFOs preserved the same conduction mechanism and (Zr 0.1667 Hf 0.1667 Pr 0.1667 Y 0.25 La 0.25 )O 2-δ possessed higher σ and lower E a than other high entropy fluorite oxides which is related to the incorporation of Pr element or the connection of cation-V o complex.
研究领域:
材料科学
·
无机非金属材料
·
固体离子学
·
功能陶瓷
·
能源材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 47
·期 19
·26869-26876
·
IF 4.527
Shao-Min Lin,Ya-Ling Yu,Ming-Feng Zhong,Huan Yang,Chen-Yang Zhang,Zhi-Jie Zhang,Wei Xu,Jiong-Yan Xie,Yu-Chun Qiu
Converting the γ phase into the α phase completely is necessary in the presintering stage of industrial alumina (Al 2 O 3 ), which requires high temperature and energy consumption. To reduce the presintering temperature, γ-Al 2 O 3 was activated by oxalic acid . XRD , 27 Al-MAS-NMR and TG-DSC were used to characterize the γ - alumina before and after activation, and the phase transformation was studied. The formation temperature of α-Al 2 O 3 decreased to 1029 °C for oxalic acid activated γ-Al 2 O 3 , and the α-fraction was 100% for activated γ-Al 2 O 3 at 1300 °C. After oxalic acid activation , the diffraction peak intensity of γ-Al 2 O 3 decreased significantly; the results of 27 Al-MAS-NMR suggested that octahedral [AlO 6 ] in γ-Al 2 O 3 was easier than tetrahedral [AlO 4 ] to be attacked by oxalic acid , and the formation of pentavalent [AlO 5 ] with higher reaction activity, which was in favour of the lowering formation temperature of α-Al 2 O 3 . The dissolution concentration of Al increased after oxalic acid activation, and the dissolution process was controlled by surface reactions. Oxalic acid mainly attacked the octahedral aluminium in γ-Al 2 O 3 and extracted Al as three complexes of [Al(C 2 O 4 )] + , [Al(C 2 O 4 ) 2 ] - and [Al(C 2 O 4 ) 3 ] 3- . Oxalic acid activated γ - Al 2 O 3 with a lower phase transformation temperature has broad application prospects in the alumina industry.
研究领域:
材料化学
·
无机化学
·
固态化学
·
工业催化
·
陶瓷材料
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2018
·
IF 3.23
Hui Liu,Sen Zhao,Zhengwen Xie,Kai Zhu,Xiaomeng Xu,Xuhan Ding,Adam Glowacz
The pyrophoric tendency of the powder of corrosion products and deposits in oil tanks was investigated by performing several series of tests in a modified self-heating experimental apparatus based on the crossing point temperature method. Three samples of the powder of corrosion products and deposits in oil tanks as well as a ferrous sulfide were used as test samples. The corresponding apparent activation energies ( E a s) were obtained: 26.1 kJ mol −1 for the corrosion products of a crude oil storage tank, 27.2 kJ mol −1 for the middle distillate oil storage tanks, and 43.5 kJ mol −1 for ferrous sulfide; the unexposed cross-point for deposits of a crude oil storage tank was at a temperature below 250 °C. Those values of E a s indicated that the corrosion products of the two oil storage tanks showed a stronger pyrophoric tendency than did the deposits of the crude oil storage tanks and ferrous sulfide. Furthermore, the E a values were similar to those of reactions reported for the incomplete oxidation of hydrogen sulfide (H 2 S), thus supporting the viewpoint that H 2 S may be considered the intermediate product for accelerating the self-heating and self-ignition of sulfide at temperatures below 250 °C and may play a major role in inducing fires and explosions in storage oil tanks. In addition, possible sources of H 2 S in self-heating of the corrosion product were largely caused by thermochemical sulfate reduction or thermal decomposition of the organic matter of oil tanks.
研究领域:
化学工程
·
安全工程
·
石油储运
·
燃烧学
·
材料腐蚀与防护
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2018
·
IF 1.686
Huaiwei Zhang,Jianbo Qi,Zhenguo Ji
Synergic effects of rare earth-magnesium based hydrides (LaH 3 -MgH 2 ) on thermal dehydrogenation of potassium borohydride (KBH 4 ) are discussed in the paper. Comparing to above 675 K for the LaH 3 -MgH 2 or KBH 4 , the dehydrogenation temperature can be decreased to 346 K for the composites (LaH 3 -MgH 2 -KBH 4 ). The apparent activation energy of desorption process for the mixture is also greatly reduced. On the other hand, the products in the temperature programmed desorption process are also illustrated.
研究领域:
材料化学
·
无机化学
·
能源材料
·
储氢材料
·
固态化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
Yongpeng Cui,Huanlei Wang,Nan Mao,Wenhua Yu,Jing Shi,Minghua Huang,Wei Liu,Shougang Chen,Xin Wang
The increasing demand for supercapacitors with high energy and power density has attracted extensive attention in designing advanced carbon materials with high accessible surface area, hierarchical porosity , and 2D/3D morphology. Here, we report a new approach to tune the morphology and structure of the nanocarbons by using methyl cellulose as the precursor. Due to the varying effect of different activating agents, the interconnected sheet-like carbon with a high surface area of up to 2285 m 2 g −1 and a thickness down to ∼4 nm can be obtained. These important characteristics make the nanocarbons demonstrate a high capacitance of 144 F g −1 at 1 A g −1 and 20 °C, and an excellent capacitance retention ratio of 64% at 100 A g −1 in ionic liquid . Because of the high fraction of meso/macropores for nanocarbons, an outstanding capacitance of 116 F g −1 can be achieved at 0 °C, with a high capacitance retention ratio of 39% at 100 A g −1 . A high energy of 16–17 and 9–10 W h kg −1 can be maintained at 20 and 0 °C when the supercapacitor is charged in less than 1s. The excellent electrochemical response of nanocarbons suggests that the proposed preparation process is promising for developing advanced carbon electrodes.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2017
·Vol. 25
·期 10
·1435-1441
·
IF 1.174
Zhirong Chen,Weitao Yang,Hong Yin,Shenfeng Yuan
The uncatalyzed reaction of p -tolyl isocyanate ( p -TI) with water in N , N -dimethylformamide (DMF) was investigated by high performance liquid chromatography (HPLC). The reactions were carried out at different temperatures from 293 K to 323 K, using various molar ratios of water to p -TI. DMF, as a special amide , was proved to be an efficient catalyst for water–isocyanate reaction. Under the reaction conditions in this study, substituted urea was the only final product observed. An appreciable amount of intermediate p -toluidine was detected. Concentrations of the isocyanate group as well as the amine and urea were determined as a function of time. New kinetic equations were deduced for each of the substance on the basis of a multistep mechanism, instead of a simple second order reaction as usual. Kinetic constants were calculated using the software MATLAB . Furthermore, the effects of temperature and concentrations of reactants on the reaction rate and amine content were discussed. The activation energy of each step was also determined.
研究领域:
物理化学
·
有机化学
·
反应动力学
·
高分子化学
·
催化化学
·
分析化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2015
·
IF 5.056
He Chen,Liang Kong,Yong Wang
Activation by nitric acid oxidation has been combined with atomic layer deposition (ALD) to modify microporous polypropylene (PP) membranes. Nitric acid oxidation with prewetting of t -butanol generates active groups on the inert surface of PP membranes. Metal oxides including Al 2 O 3 and TiO 2 are subsequently ALD-deposited on the activated membrane. Nitric acid oxidation is a mild approach to activate PP membranes. A short immersion in nitric acid for 10 min is able to generate oxygen/nitrogen-containing active species on the membrane surface , which leads to an evident increase (38%) in the membrane permeability. The mechanical stability and the integrity of the porous structure are well preserved after activation. Surface elemental analyses and microscopy observations confirm the successful deposition of metal oxides thin layers onto the activated membranes. In the deposition of either Al 2 O 3 or TiO 2 , the hydrophilicity of the deposited membranes is continuously improved with increasing ALD cycles, resulting in further increase in water flux. After 100 ALD cycles, the flux is doubled compared to that of the bare membrane. Al 2 O 3 is more efficient in enhancing the hydrophilicity and permeation than TiO 2 under identical deposition conditions because of the faster growth of Al 2 O 3 on the activated PP surface.
研究领域:
材料科学
·
膜技术
·
表面化学
·
高分子化学
·
化学工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 4
·5337-5346
·
IF 3.741
Chuangang Yao,Jixing Yang,Haixia Zhang,Sigeng Chen,Jian Meng,Kedi Cai
Summary Cu doped perovskites SrFe 0.9- x Cu x Mo 0.1 O 3- δ (SFCM, x = 0-0.2) are explored as cathodes for IT-SOFCs. The influence of Cu doping on the property of SFCM series was studied in detail. The oxygen content decreases with the increase of Cu doping amount. SFCM samples are chemically compatible with LSGM electrolyte. However, the TEC values are still a bit higher than that of some common SOFC electrolytes. At 750°C, the R p values are 0.261, 0.227 and 0.155 Ω·cm 2 for SFCM0, SFCM0.1, and SFCM0.2. The obtained activation energies for x = 0, 0.1, and 0.2 are 1.01, 0.98, and 0.87 eV, respectively. These results indicate that Cu doping into SrFe 0.9- x Cu x Mo 0.1 O 3- δ has a favorable effect on the electrochemical activity of the materials.
研究领域:
材料科学
·
电化学
·
能源材料
·
固体氧化物燃料电池
·
无机功能材料
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Xu Zhang,Fan Yang,Jialing Qin,Huanghu Peng,Zezhou Chen,Lei Che,Shouxin Zhu,Wei Yang
The heterogeneous catalyst of CeO 2 /ZSM5 was applied to hydrolyze Congo red in subcritical water for the first time in the present study. The hydrolysis rate of Congo red could be significantly accelerated by introducing only 5 mg of 5% CeO 2 /ZSM5. The Congo red could be completely hydrolyzed at 220°C for 2 min—a reaction temperature 40°C lower than in the absence of 5% CeO 2 /ZSM5. In addition, the 5% CeO 2 /ZSM5 could be recycled for another run, and its Congo red hydrolysis efficiency and surface morphology showed no obvious change after 3 runs of recycling. The hydrolysis kinetics of Congo red in subcritical water could be well expressed by the Weibull model. The activation energy for hydrolysis of Congo red in subcritical water in the presence of 5% CeO 2 /ZSM5 (104.8 kJ mol –1 ) was much lower than in the absence of 5% CeO 2 /ZSM5 (155.9 kJ mol –1 ). The frequency factors were calculated to be 8.1 × 10 9 and 1.9 × 10 14 min –1 in the presence and absence of 5% CeO 2 /ZSM5, respectively. With these excellent properties, 5% CeO 2 /ZSM5 may prove to be an advantageous catalyst for the hydrolysis of Congo red in textile wastewater, in subcritical water.
研究领域:
环境化学
·
催化化学
·
水处理技术
·
绿色化学
·
反应动力学
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2021
·
IF 3.383
Daifeng Wu,Rui Li,Tai Sun,Renheng Tang,Fangming Xiao
Mg/MgH 2 as a thermochemical energy storage (TCES) material suffers from a slow hydrogenation-dehydrogenation kinetic and poor reversibility. Addition of metal oxide is an effective way to improve the kinetic properties of Mg/MgH 2 . However, there is little study on the effects of complex oxides . Thus, the catalytic effects of complex metal oxides and its catalytic mechanism were investigated in this paper. Results show that the dehydrogenation peak temperature and apparent activation energy of MgH 2 -Ta 2 O 5 are 320.8 °C and 128.54 kJ/mol. Combined with complex metal oxide, MgH 2 -Ta 2 O 5 -Nd 2 O 3 could further reduce the dehydrogenation peak temperature (307.2 °C) and apparent activation energy (95.33 kJ/mol). MgO and NdH 2.61 are found in the dehydrogenated MgH 2 -Ta 2 O 5 -Nd 2 O 3 , indicating that n-typed oxide Ta 2 O 5 and p-typed oxide Nd 2 O 3 are formed and improved the kinetics properties of MgH 2 . Furthermore, Nd 2 O 3 /Ta 2 O 5 interface is formed and acted as “p-n junction”. When heating, the “p-n junction” is exposed to thermal radiation and produce electrons and holes, and then the kinetics properties of MgH 2 are further enhanced.
研究领域:
材料科学
·
能源化学
·
物理化学
·
无机功能材料
·
热能存储
✓ 已验证
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2019
·
IF 2.6
Ang Qiao,Haizheng Tao,Yuanzheng Yue
Amorphous conductors with high ionic conductivity are a promising candidate as electrolytes in all-solid state batteries. In this work, we prepared amorphous Ag 3 PS 4 conductor via a chemo-mechanical milling process, and then characterized its structure and electrochemical properties . The results show that Ag + conductivity of the amorphous Ag 3 PS 4 was remarkably enhanced by three orders of magnitude compared to its crystalline counterpart. Furthermore, the amorphous sample exhibits lower activation energy ( E a ) for ionic conductivity as a function of temperature. Structural characterizations indicate that the tetrahedral [PS 4 ] units were retained in amorphous Ag 3 PS 4 , but the Ag + ions became more liberated than those in the crystalline state, leading to the enhanced migration of Ag + ions, thereby, the ionic conductivity in amorphous Ag 3 PS 4 is drastically increased. This work provides insight into the crucial role of the disorder in raising the ionic conductivity of amorphized chalcogenide materials containing mobile ions.
研究领域:
材料科学
·
固体化学
·
能源材料
·
电化学
·
无机非金属材料
·
固态电池
·
离子传导
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）