Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 32
·12835-12848
·
IF 0
Zhanjun Chen,Ruirui Zhao,Peng Du,Hang Hu,Tao Wang,Licai Zhu,Hongyu Chen
Alternative micro-sized LiNi0.5Mn1.5O4 spinels with octahedral structure (showing only one type of {111} crystal face) or chamfered polyhedral structure with extra other faces have been synthesized via a controllable method. A possible growth model, complexing–pyrolyzing-oriented, is also proposed for the formation of chamfered polyhedral LiNi0.5Mn1.5O4 spinel based on the experimental results in this paper. The chamfered polyhedral LiNi0.5Mn1.5O4 can provide a large capacity of 103 mA h g−1 even at a discharge rate as high as 50 C, which is far superior to that of the octahedral structure. Besides, the capacity retentions of the chamfered polyhedral composites are found to be 90.82% at 25 °C after 500 cycles and 90.00% at 55 °C after 200 cycles, which are also better than those of the octahedral composites. These results represent the first experimental evidence for lattice-plane anisotropy in LiNi0.5Mn1.5O4 crystals. Moreover, the pseudo-sphere structure is beneficial for obtaining high volumetric energy density and excellent processability in practical applications. In short, we have revealed for the first time that, through chamfering an octahedron to a pseudo-sphere-like polyhedron rather than doping or coating, a micro-sized LiNi0.5Mn1.5O4 spinel with good compatibility between energy/power density and cycle life can be synthesized successfully without sacrificing other properties.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机固体化学
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纳米结构材料
✓ 已验证
DOI
JOURNAL OF POWER SOURCES
·
2023
·
IF 9.2
Tianyao Ding,Dong Zheng,Huainan Qu,Weixiao Ji,Xiaoxiao Zhang,Dongping Lu,Gongwei Wang,Deyang Qu
An in-situ electrochemical optical diagnosis is the key to the investigation of electrode interface during a redox reaction . Because the morphology changes particularly, dendrite formation, dendrite shapes, solid electrolyte interface formation and gas generation can be revealed visually. The challenge of ensuring uniform current density on a flat Li anode in a liquid electrolyte is addressed and uniform Li plating is demonstrated. The dendrite shape change under different reduction current density is discussed. The Li dendrite shape change and the performance of Li anodes with a surface lamination of graphite and red phosphate are used as examples to demonstrate the capability of the in-situ optical cell. An in-situ electrochemical optical cell used in the investigation of the increasingly popular solid-state Li batteries has its own challenges. Due to the untransparent nature of a solid-state electrolyte, an optical investigation on a solid-state electrolyte Li battery needs to be done by exposing the cross-section of the cell. In addition, it is very difficult to assemble an optical cell with a brittle and fragile solid-state electrolyte in a glove box. A set of formation and transfer dies, and an optical cell are introduced. The Li dendrite growth at the interface can be observed in a solid-state Li cell.
研究领域:
电化学
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材料科学
·
能源存储
·
固态电池
·
界面科学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Ziang Xie,Ping Wu,Sen Chen,Shiping Zhang,Yili Pei,Li Li,Guodong Fu,Ying Xie,Haochen Guan,Yun Xing,Jianzhang Zhu,Xinran Wang
The power conversion efficiency (PCE) of tin-based perovskite solar cells (TPSCs) was significantly improved when polyvinyl pyrrolidone (PVP) was doped into the formamidinium tin iodide (FASnI 3 ) layer with an optimized doping mass. After doping, the FASnI 3 grain size, film smoothness and average carrier lifetime were largely enhanced, which demonstrate the crystallization quality improvement to FASnI 3 . The champion PCE of the enhanced TPSC was improved to 7.83%, which is relatively 27% larger than that of the control, 6.15%. After continuous storage for 15 days, the PCE of the enhanced TPSC remained 74.4% of its original value. Using the finite difference time domain (FDTD) simulation method, we demonstrated that the light absorption ratio of the FASnI 3 :PVP layer was larger than that of the FASnI 3 , and the photo-generated carrier density of the enhanced TPSC was approximately 2% ∼ 3% larger than that of the control. The ultimate efficiency of the enhanced TPSC was calculated to be 26.23%. It is potential to dope PVP into FASnI 3 to further enhance the device performance of TPSCs.
研究领域:
材料科学
·
光伏技术
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纳米科技
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表面化学
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半导体器件
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
·
2018
·Vol. 2018
·期 1
·1465760
·
IF 2.207
Jiamao Li,Jingwei Hou,Yu Gong,Chengjian Xiao,Lei Yue,Linjie Zhao,Huan Ma,Heyi Wang,Shuming Peng,Chao Chen,Hongli Chen
A liquid-phase reducing method of synthesizing Pt nanocrystals was demonstrated, and dendrite-, cube-, and cuboctahedron-shaped Pt nanocrystals (NCs) with well-defined monomorphic were successfully synthesized through iodine ions mediated with the CTAB agent. When the KI concentration was increased to thirty times of K 2 PtCl 4 at the nucleation stage, the high-quality Pt nanodendrites could be obtained. However, no matter how many KI were added at the growth age, only cube- and cuboctahedron-shaped Pt nanocrystals formed. The results of high-resolution TEM, EDX, and XRD indicated that the size and shape of Pt NCs could be turned by changing the concentration and time of KI. In the nucleation stage, it might be due to that some iodine ions adsorb on the surfaces of Pt NCs, which probably cause the rapid growth process resulting in the formation of Pt nanodendrites. In the growth stage, although high concentrations of I − ions could contribute to the shape control and generate bigger particles of Pt NCs, small Pt particles do not grow into dendrites. The insight into the role of I − ions in synthesis of Pt NCs reported here provided a viewpoint for clearly understanding the formation mechanism of anisotropic platinum nanostructures.
研究领域:
纳米材料科学
·
物理化学
·
无机合成
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催化化学
·
材料表征技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Shiqi Sun,Yanjun Chen,Qiang Bai,Zhen Tian,Que Huang,Changcheng Liu,Shengnan He,Yaxiong Yang,Yanzhong Wang,Li Guo
Researchers are accustomed to utilizing traditional solid-state and sol–gel routes to synthesize Na 3 V 2 (PO 4 ) 3 (NVP). No regulation mechanism is proposed to illustrate the growth process of NVP in solvothermal environment. In current work, uniform spherical particles with positive charge are synthesized by molecular self-assembly of nanosphere micelles using structural guiding agent polyethylene glycol (PEG) and surfactant Cetyltrimethylammonium bromide (CTAB). Nanoflower-shaped NVP sample is successfully prepared in the 100 % methyl alcohol medium, derived from the plate V 2 O 5 (negative charge) combining with the nuclear nanospheres (positive charge) with the induction of electrostatic attraction. Based on the multi-dimensional tests and molecular dynamic calculation, the protective mechanism of polar solution for NVP system is proposed for the first time, that is, methanol solvent system can better protect the morphological features of NVP than water environment to maintain the original special nanoflower morphology. Due to the distinctive and stabilized nanoflower construction, the optimized NVP60 sample can provide more extra active sites for the efficient de-intercalation of Na + and possess a large contacting area with electrolyte, resulting in the facilitated kinetic characteristics and superior electrochemical performance. The optimized NVP60 cathode possesses superior sodium storage property in both half cell and full cell. This work proposes a synergetic strategy combining theory and experiment to design and synthesize the modified NVP-based cathode materials from the molecular bonding aspect, further promoting the development of high performance cathode for SIBs.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
无机化学
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计算材料学
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电池技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Hua Tian,Kaixin Zhu,Wang Li,Lin Wang,Zhifeng Yu,Yuannan Lai,Yunyi He
Ni-Co layered double hydroxide (NCLDH) with nitrate anions as interlayer counter ions was obtained via an oxidation-induced anion intercalation process. The optimization on the tunable proportion between divalent and trivalent metal cations in NCLDH host layers is realized in the dependence on the regulation of the additive amount of hydrogen peroxide as an oxidizing agent. The increase of trivalent metal cations facilitates the intercalation of nitrate anions into the interlamellar region between NCLDH host layers. Importantly, the electrostatic interaction between NCLDH host layers and interlayer anions results in the formation of hierarchical flower-like morphologies towards the enhancement of specific surface areas. Moreover, the increase in number of interlayer nitrate anions expands effectively interplanar spacing between NCLDH host layers. Remarkably, this unique structure not only accelerates the diffusion process of active hydroxide anions in the bulk phase of LDH, but also strengthens the stability of the hierarchical structure during electrochemical reactions. The electrochemical evaluation shows that NCLDH-16 achieves a superior specific capacity of 802 C g −1 at a current density of 1 A g −1 with a capacity retention of 86.7% as the increase of current densities to 10 A g −1 . The NCLDH-16//AC hybrid supercapacitor delivers a maximum energy density of 37.6 Wh kg −1 at a power density of 800 W kg −1 as well as still retains 87.4% of the initial capacitance after 10 000 cycles, suggesting great potential in practical energy storage devices.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
功能材料
·
电化学能量存储
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2019
·Vol. 19
·期 1
·57-65
·
IF 1.093
Liu Wolong,Zhang Jiupeng,Liu Qi,Pei Jianzhong,Zhu Cunzhen,Liu Peng
Micro-damages always occur and accumulate in asphalt pavement materials under the effects of temperature, vehicle loads and other factors during service. Accordingly, self-healing microcapsules could be added into asphalt binder and repair micro-damages to prevent damage extension in
time. In this study, the emulsified rejuvenator and melamine-urea-formaldehyde resin (MUF) were selected as the core and cyst wall materials, respectively, and in-situ polymerization method was applied to synthesize the novel microcapsules. The effects of emulsifier dosage and curing
time were revealed on the particle size, dispersion, surface morphology and coating properties, and the optimum process parameters were determined for microcapsules. Then, the micro morphology, molecular structure, and thermal stability were further investigated to determine the optimal preparation
of the microcapsules. Finally, the linear amplitude sweep (LAS) test was performed to evaluate the self-healing efficiency of the asphalt binder with different dosages of prepared microcapsule, and the optimal dosage of microcapsules was determined as 0.5%.
研究领域:
材料科学
·
土木工程
·
化学工程
✓ 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）