SOLID STATE IONICS
·
2016
·
IF 2.38
Guofeng Xu,Qingrui Xue,Jianling Li,Zhanyu Li,Xinping Li,Tianheng Yu,Jiguang Li,Xindong Wang,Feiyu Kang
Lithium-excess layered cathode materials Li[Li 0.2 Mn 0.54 − x Sm x Co 0.13 Ni 0.13 ]O 2 (x = 0, 0.01, 0.03, 0.05) with different quantities of Sm were synthesized by the coprecipitation-calcination method. The rare earth element samarium (Sm) was introduced into the structure of Li[Li 0.2 Mn 0.54 Co 0.13 Ni 0.13 ]O 2 as the replacement at Mn sites. The refinement unit cell parameters from the X-ray powder diffraction patterns illustrate the doping of Sm facilitates enlarging the lithium ions diffusion passageway space of the Li[Li 0 . 2 Mn 0.54 Co 0 . 13 Ni 0.13 ]O 2 structure. The Li[Li 0.2 Mn 0.51 Sm 0.03 Co 0.13 Ni 0.13 ]O 2 electrode presented the best electrochemistry properties. The initial discharge capacity is 287.5 mAh g − 1 and the initial coulombic efficiency increases from 81.31% to 85.34% with a constant current density of 12.5 mA g − 1 , which can be attributed to the suppression of the oxygen release from the structure at the initial charge-discharge process. The Li[Li 0·2 Mn 0.51 Sm 0.03 Co 0.13 Ni 0.13 ]O 2 electrode delivers 236.1 mAh g − 1 after 40 cycles and the capacity retention ratio is 82.12% while only 206.8 mAh g − 1 and 70.85% are obtained after 40 times of cycling for the pristine electrode. The Nyquist plots indicate that the electrical conductivity and interfacial electrochemical reaction activity increase as well.
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产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2014
·
IF 4.835
Sujie Chang,Shigang Ruan,Erlong Wu,Weixin Huang
Oxide-on-metal particles with exposed interfaces exhibit wealthy structures and functions, but their facile synthesis remains as a challenge. Herein we report a facile O2-assisted hydrothermal method to synthesize CeO2-on-Ag particles with different CeO2 thicknesses. In this novel approach Ag particles catalyze the O2 + H2O reaction to form surface hydroxyls that induce the preferential nucleation of Ce(OH)3 on the surfaces of Ag particles, eventually forming CeO2 adlayers on Ag particles. CeO2-on-Ag particles exhibit the CeO2 thickness-dependent SERS effect in which their best SERS effect is 2 orders stronger than that of Ag particles. They also exhibit CeO2 thickness-dependent catalytic performance in CO oxidation in which the best one is as active as traditional CeO2-supported Ag catalyst. These results open up new opportunities to synthesize oxide-on-metal particles and explore their functions by tuning the oxide adlayer thickness.
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DOI
高影响因子
MATERIALS LETTERS
·
2014
·
IF 2.269
Ming Yan,Yan Yan,Chao Wang,Wei Lu,Weidong Shi
In this letter, Ni 2+ doped InVO 4 nanocrystals were successfully synthesized by a simple one-pot microwave-assisted method. The energy bandgap of obtained samples can be precisely controlled by varying the Ni 2+ doping amount. The O 2 production rate of obtained Ni–InVO 4 nanocrystals is higher than that of pure InVO 4 nanocrystals under visible-light, which can be ascribed to the narrowed band gaps. The corresponding 1% doped sample N1 has the highest O 2 production rate (394 μmol/h) in all samples, which is 66% higher than the undoped sample N0.
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DOI
高影响因子
GREEN CHEMISTRY
·
2014
·Vol. 17
·期 1
·335-342
·
IF 6.852
Muge Niu,Yucui Hou,Shuhang Ren,Wenhua Wang,Qitian Zheng,Weize Wu
Conversion of cellulose, the most abundant biomass, shows a high selectivity to yield formic acid (FA), when oxidized by O2 in NaVO3–H2SO4 aqueous solution. This conversion involves various reactions including hydrolysis and oxidation. In this work, the relationships between these reactions were studied. There are mainly two hydrolyses and two oxidations occurring in the conversion: initial hydrolysis (from cellulose to monosaccharides) and deep hydrolysis (from monosaccharides to levulinic acid); catalytic oxidation (from monosaccharides to FA) and ordinary oxidation (from levulinic acid to acetic acid). Among these four reactions, catalytic oxidation to FA and deep hydrolysis to byproducts are competitive. The increasing rate of deep hydrolysis is faster than that of catalytic oxidation, when temperature is increased. Catalytic oxidation is promoted and deep hydrolysis is suppressed, when the O2 pressure is increased. Moreover, deep hydrolysis is promoted and catalytic oxidation is suppressed, when H2SO4 concentration is increased. The hydrolysis–oxidation pathway of this conversion was proposed. Thus, the byproducts could be inhibited, and FA-oriented transformation could be realized.
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DOI
高影响因子
Journal of Energy Storage
·
2022
·
IF 8.907
De-Ming Zhu,Fan Bai,Yi-Nan Zhang,Ya-Nan Yang,Zhuang Sun,Jun-Wen Deng,Tao Zhang
Solid-state Li-O 2 batteries (SSLOBs) have been denoted as the holy grail in next-generation Li metal batteries for their high theoretical energy density , manipulation of ambient air to energy storage as well as high safety. However, the solid rigid interfaces both at the cathode and anode side introduce ultra-high resistances in the battery system and impede its operation under ambient temperature. Moreover, the high-reductive Li anode and semi-open cathode would cause severe side reactions during cycling which further degrade battery performance. To manage the above-mentioned issues, a rationally designed SSLOBs based on plastic crystal electrolyte is proposed in this study to enable SSLOBs operation at ambient temperature and in full charge-discharge mode. The brand-new Li-O 2 battery has been improved mainly from two aspects. First, we propose a polyacrylonitrile (PAN) modified succinonitrile (SN) electrolyte (PAN-SN) to retard the polymerization of SN and meanwhile suppress the degradation of Li ionic conductivity. Second, we propose an alternative mixed electron/ion complex conductor (MEIC) cathode to coordinate with plastic crystal electrolyte with an expanded Li-O 2 reactive zone and improved interfacial charge transfer during the charge-discharge process. The fabricated flexible SSLOBs based on PAN-SN electrolyte and MEIC cathode could be successfully fully charged-discharged (cutoff 2.0–4.5 V) for tens of cycles at ambient temperature under simulated air condition (20 vol% oxygen), with high-capacity retention of around 85 %.
研究领域:
能源存储
·
电池技术
·
材料科学
·
电化学
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DOI
高影响因子
NANOTECHNOLOGY
·
2019
·Vol. 30
·期 36
·364003
·
IF 3.399
Chao Li,Yijie Liu,Bojie Li,Fan Zhang,Zhu Cheng,Ping He,Haoshen Zhou
All-solid-state Li–O2 batteries are receiving intense interest because of the substitution of solid electrolytes for toxic and flammable liquid electrolytes. However, new issues are arising in the aspect of the electrolyte cathode interface. On the one hand, in a traditional sandwiched battery structure, the reaction sites of the cathode are restricted to the finite planar electrode–electrolyte interface, resulting in limited performance of all-solid-state Li–O2 batteries. On the other hand, integrating the electrolyte with the cathode to achieve good interfacial contact often requires complex sintering processes. Herein, this work reports a solid electrolyte cathode assembly (SECA) which consists of a dense Li1.5Al0.5Ge1.5P3O12 (LAGP) layer and a carbon coated porous LAGP layer fabricated by facilely one-step sintering. As a result, Li–O2 batteries adopting the SECA showed a relatively high discharge capacity of 0.48 mAh cm−2 at 5 μA cm−2. Besides, the batteries could sustain six full cycles with a restricted capacity of 0.08 mAh cm−2 at 10 μA cm−2. It was found that the high capacity can be attributed to the high surface area of porous cathode structure.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
Journal of Physical Chemistry C
·
2014
·
IF 4.835
Wugang Fan,Xiangxin Guo,Dongdong Xiao,Lin Gu
Gold nanoparticles (AuNPs) anchored to vertically aligned carbon nanotubes (VACNTs) act as additional nucleation sites for the Li2O2 growth, leading to the decreased size while increased density of Li2O2 particles in process of discharge. Correspondingly, at the deep discharge to 2.0 V the batteries show increased specific capacity. Upon charge, the AuNPs exhibit promotion effect on the Li2O2 decomposition by improving the conduction property of the discharge-formed particles, rather than by imposing the conventional electrocatalytic effect on the oxygen evolution reaction. Moreover, the AuNPs show promotion effect on decomposition of carbonate species arising from the side reactions. These effects consequently lead to the reduced charge overpotentials and extended cycle operation of the batteries. The results here provide a new as well as clear picture on the role of incorporated AuNPs in the Li2O2 formation and decomposition, which would be helpful for better understanding and constructing of high-performance air cathodes.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
·
IF 8.247
Kang-Ning Gao,Hao-Ran Wang,Ming-Hui He,Yi-Qiu Li,Zhong-Hui Cui,Ya Mao,Tao Zhang
The development of solid-state lithium-oxygen batteries is currently limited primarily by the high solid-solid interfacial resistance and the lack of efficient assembly of electrolyte and electrode. In this work, noncovalent interactions between the cations of an ammonium ionic liquid and both solid electrolytes and carbon air cathodes are introduced. The ionic liquid-based electrolytes (ILE) are solidified on Li 6·40 La 3 Zr 1·40 Ta 0·60 O 12 (LLZTO) nanoparticles and gelated by multi-wall carbon nanotubes (MWCNTs), respectively, to construct LLZTO@ILE quasi-solid-state electrolyte (QSSE) and MWCNTs-LLZTO/ILE gel cathode (GC). The QSSE exhibits a high ionic conductivity of 1.71 × 10 −3 S cm −1 at 60 °C, high Li-ion transference number of 0.56, broad electrochemical window of ~4.8 V and good thermal stability . The GC shows outstanding compatibility with QSSE. Quasi-solid-state Li–O 2 batteries are assembled by integrating QSSE and GC films with a facile roll forming method, showing a low total interfacial resistance (~87 Ω cm 2 ), and excellent reversible cycles (70 cycles) with low charge overpotential (<0.44 V) and quite high electrical energy efficiency (>70%) at 60 °C and 200 mA g −1 . A 0.12 Ah pouch-type Li–O 2 battery was achieved by this method. These results suggest that the noncovalent interactions initiated by IL cations could be an effective approach to solve the solid-solid interface issue and achieve high discharge capacity in solid-state energy storage devices.
研究领域:
材料科学
·
电化学
·
能源存储
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Binbin Shao,Yufan Chen,Deli Wu,Chaomeng Dai,Yalei Zhang
Structural Fe(II/III) hydroxides on the shell of nano-zerovalent iron (nZVI) are reactive sites for As(III) adsorption. Well-controlled structural Fe(II) hydroxides (SFH) is prepared to serve for As(III) removal in present study. With oxygen As(III) removal by SFH occurred efficiently but the removal efficiency was greatly reduced under anoxic conditions. The mineral transformation from SFH to lepidocrocite probably contributed to the robust removal efficiency of As(III). It is found that Cu(II), Cr(VI) and NO 2 − in aqueous solution could act as oxidants and promote the mineral transformation of SFH. A more efficient As(III) removal was therefore observed without oxygen. The removal efficiency decreased in the order O 2 /SFH ≈ Cu(II)/SFH > Cr(VI)/SFH ≈ NO 2 − /SFH at near neutral pH. The removal efficiency was less dependent on the initial pH for O 2 /SFH and Cu(II)/SFH systems than Cr(VI)/SFH and NO 2 − /SFH systems. Distribution of As on solid phases was able to describe the removal mechanism of As(III), and the results showed that the mineral transformation promoted the precipitation process and inhibited outer-sphere complexation, thus leading to enhanced As removal. With Cu(II), Cr(VI) and NO 2 − , the generation of oxidants from SFH transformation drove As(III) oxidation, and contributed to total As removal.
研究领域:
环境科学
·
化学
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DOI
高影响因子
Nano Research
·
2018
·Vol. 12
·期 3
·517-523
·
IF 7.994
Liu Tie,Wang Leidanyang,Huang Tao,Yu Aishui
Design and fabrication of framework-structured porous precursors have been regarded as a prospective albeit challenging strategy to obtain bimetal/NC-enriched bifunctional elecrocatalysts. In this work, an effective bottom-up approach involving solution-based self-assembly and a post-annealing process was developed to confine (Co, Zn)-N-C active sites into N-enriched graphitic carbon nanocages. This novel architecture containing N-doped-C stabilized bimetallic nanoparticles derived from ZIF precursors was well-studied by a series of characterization and analysis techniques. Details were given that these well-dispersed (Co, Zn) nanoparticles were encapsulated into the pyridinic-N-dominated graphitic carbon nanocage with a total metal loading of approximately 7.4 at.%. This favorable hierarchical structure not only enhances the electron conductivity, but also owns a sufficient BET surface area facilitating the gas-liquid-solid triphase reaction and producing more space to store discharge products. Importantly, results infer that the interesting nanoframes manifests a satisfying ORR/OER activity and enhanced cell performance whether liquid or solid-state electrolytes are used. As such, our work rationalizes that this type of cage-shaped bimetal-N-C material is promising for high-performance Li-O 2 batteries.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源存储
·
功能材料
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DOI
高影响因子
Science China-Materials
·
2016
·Vol. 59
·期 8
·618-628
·
IF 0
Yi Ting-Feng,Han Xiao,Yang Shuang-Yuan,Zhu Yan-Rong
Layered Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 (0 ≤ x ≤ 0.08) cathode materials were successfully synthesized by a sol-gel method. X-ray diffraction and the refinement data indicate that all materials have typical α-NaFeO 2 structure with R -3 m space group, and the a -axis has almost no change, but there is a slight decrease in the c lattice parameter as well as the cell volume. Scanning electron microscopy and high resolution transmission electron microscopy prove that all the samples have uniform particle size of about 200–300 nm and smooth surface. The energy-dispersive X-ray spectroscopy mapping shows that aluminum has been homogeneously doped in the Li 1.2 Mn 0.56 Ni 0.16 Co 0.08 O 2 cathode material. The cyclic voltammetry and electrochemical impedance spectroscopy reveal that appropriate Al-doping contributes to the reversible lithium-ion insertion and extraction, and then reduces the electrochemical polarization and charge transfer resistance. Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x = 0.05) shows the lowest charge transfer resistance and the highest lithium-ion diffusion coefficient among all the samples. The Li-rich electrodes with low-level Al doping shows a much higher discharge capacity than the pristine one, especially the Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x = 0.05) sample, which exhibits greater rate capacity and better fast charge-discharge performance than the other samples. Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x = 0.05) also exhibits higher discharge capacity than the pristine one at each cycle at 55°C. These results clearly indicate that the high rate capacity together with a good high rate cycling performance and high-temperature performance of the low-Co Li 1.2 Mn 0.56 Ni 0.16 Co 0.08− x
Al
x
O 2 ( x =0.05) is a promising alternative to next-generation lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
储能技术
·
锂离子电池
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DOI
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2020
·Vol. 38
·期 4
·5475-5484
·
IF 5.627
Jianghui Luo,Qianjin Lin,Wenxiang Xia,Yizhuo He,Mei Mei,Lixin Lu,Yang Liu,Chun Zou
Pressurized oxy-fuel combustion has been attracting increasing attentions due to its improved efficiency and low cost. The present study reports ignition delay times (IDTs) of pyridine under O 2 /CO 2 atmospheres within a temperature range from 1202 to 1498 K at pressures from 2.2 to 10 bar for equivalence ratios of 0.5, 1.0, and 2.0. The experimental results were compared with the IDTs of pyridine under O 2 /Ar atmospheres from MacNamara et al.. The comparison results indicate that the IDTs of pyridine under O 2 /CO 2 atmospheres are evident longer than those under O 2 /Ar atmospheres even at low pressure. A modified kinetic model (HUST pyridine Model) was proposed based on our previous mechanism. HUST pyridine Model predicted well the IDTs under both O 2 /CO 2 and O 2 /Ar atmospheres obtained in shock tubes and the species profiles under both O 2 /CO 2 and O 2 /N 2 atmospheres obtained in plug flow reactors . HUST pyridine Model, Alzueta Model, and Pyridine LTO Model were evaluated. The results show that the performance of HUST pyridine Model is much better than Alzueta Model, and Pyridine LTO Model. The main reason is that the net reaction rate of C 5 H 5 N + O = C 5 H 4 N + OH in HUST pyridine Model is much faster than that in Aluzeta Model. The effect of CO 2 on the ignition of pyridine at elevated pressures has been analyzed in detail. The oxidation pathways of pyridine are also analyzed at different pressures.
研究领域:
燃烧化学
·
化学动力学
·
能源工程
·
燃料科学
·
高压物理
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DOI
高影响因子
危险品化学品经营许可证（带存储）