ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Hui Zhuang,Yubo Bao,Yake Nie,Yunxian Qian,Yuanfu Deng,Guohua Chen
To overcome the problems faced by the preparation of high-performance LiFe 0.5 Mn 0.5 PO 4 /C cathode material for commercial application in large scale, such as complicated procedures in the synthesis process and/or low volumetric energy density of nanometer-sized sample, herein, micro-agglomerated LiFe 0.5 Mn 0.5 PO 4 /C is prepared by a facile surfactant-assisted solid-state route. A composite carbon source and controllable pre-calcining process are used for achieving the homogenous carbon coating, interconnected pores and uniform particle size distribution . X -ray powder diffraction, Raman spectrum , N 2 -adsorpotion-desorpotion, scanning/transmission electron microscopy and elemental analysis confirm the microstructure and accurate composition of the as-prepared samples. It is found that the composite source not only increases the homogeneity of the carbon coating layer and the pore-forming ability, but also contributes to inhibiting the size growth of the primary particles. Meanwhile, the suitable pre-calcining time can improve the specific surface area and optimize the carbon content and pore structure , and thus enhance the tap density of the as-prepared material. The typical LiFe 0.5 Mn 0.5 PO 4 /C sample with carbon content of 3.50 wt% displays high reversible capacities and good rate capability, with discharge capacities of 155.0, 141.5 and 120.1 mA h g −1 at 0.1, 1.0 and 5.0 C (1 C = 170 mA g −1 ), respectively. Furthermore, the sample exhibits superior cycling performance, with a capacity retention above 98% after 200 cycles at 1.0 and 5.0 C. As a result, this LiFe 0.5 Mn 0.5 PO 4 /C exhibits great potential as a cathode material for high power/energy lithium ion batteries because of its easy synthesis, high specific capacity, good rate capability and cycle stability.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2021
·
IF 6.024
Kaibin Fang,Qian Xie,Chengyun Wang,Xiulian Qiu,Yali Wang,Wei Yang,Xin-wei Yu
LiNi0.8Co0.15Al0.05O2 (LNCA) cathode materials have an extremely high energy density, which can greatly enhance the driving range of pure electric vehicles if they are used in on-board batteries. However, the development of the LNCA cathode material is restricted by the expensive transition metal cobalt (Co). Therefore, researchers are devoted to finding other metals to replace Co to synthesize nickel (Ni)-rich Co-free materials to reduce the cost. To investigate the feasibility of replacing Co with manganese (Mn) as a transition metal, this paper reports the synthesis and compares the properties of four Ni-rich materials with different Co–Mn contents by gradually adding Mn to LNCA materials and reducing the Co content in equal amounts using an oxalic acid coprecipitation method. The results show that Mn can compensate the effect of Co deficiency to a certain extent; it is feasible to use Mn to completely replace Co in the synthesis of Ni-rich ternary Co-free materials under the premise of sacrificing a certain initial specific capacity. The tetrameric material LiNi0.8Co0.1Mn0.05Al0.05O2 substituted with trace amounts of Mn exhibited the most excellent electrochemical properties among the four synthesized materials. Therefore, to synthesize satisfactory Ni-rich Co-free materials, it is suggested to develop and synthesize quaternary Co-free materials on the basis of LiNi0.8Co0.1Mn0.05Al0.05O2.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2016
·Vol. 21
·期 1
·125-131
·
IF 2.327
Ren Yurong,Lu Peng,Huang Xiaobing,Ding Jianning,Wang Haiyan
Li 2 ZnTi 3 O 8 /C nanocomposite has been synthesized using phenolic resin as carbon source in this work. The structure, morphology, and electrochemical properties of the as-prepared Li 2 ZnTi 3 O 8 samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), Raman spectroscopy (RS), galvanostatic charge–discharge, and AC impedance spectroscopy. SEM images show that Li 2 ZnTi 3 O 8 /C was agglomerated with a primary particle size of ca. 40 nm. TEM images reveal that a homogeneous carbon layer (ca. 5 nm) formed on the surface of Li 2 ZnTi 3 O 8 particles which is favorable to improve the electronic conductivity and inhibit the growth of Li 2 ZnTi 3 O 8 during annealing process. The as-prepared Li 2 ZnTi 3 O 8 /C composite with 6.0 wt.% carbon exhibited a high initial discharge capacity of 425 and 159 mAh g −1 at 0.05 and 5 A g −1 , respectively. At a high current density of 1 A g −1 , 95.5 % of its initial value is obtained after 100 cycles.
研究领域:
材料科学
·
纳米技术
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2019
·Vol. 97
·期 12
·3002-3011
·
IF 1.61
Jie Ren,Yi-Ling Liu,Li Feng,Chun-Wei Liu
The electrochemical preparation of NaClO has been widely used for the production of industrial disinfectant. To reduce the cost of electrode preparation using the brushing method, this paper introduces a method for the electrodeposition for RuO 2 /Ti and RuO 2 -IrO 2 /Ti preparation and NaCl solution electrolysis. The deposition of Ir improves the uniformity and stability of the RuO 2 /Ti electrode. The optimum preparation conditions and additive concentrations were investigated in detail through the orthogonal experiment. By adjusting the electroplating time, temperature and voltage, the electrode with a high content of available chlorine was synthesized successfully. The physicochemical properties of the as-prepared RuO 2 /Ti and RuO 2 -IrO 2 /Ti were determined by XRD, SEM-EDS, and XPS, and the electrochemical performance and lifetime of the RuO 2 /Ti and RuO 2 -IrO 2 /Ti was verified via an electrochemical workstation. Uniform and stable RuO 2 /TiO 2 and RuO 2 -IrO 2 /TiO 2 were synthesized successfully for the electrolysis of the NaCl solution.
研究领域:
材料科学
·
电化学工程
✓ 已验证
DOI
高影响因子
Nano-Micro Letters
·
2021
·Vol. 13
·期 1
·1-13
·
IF 16.419
Qu Danyao,Jian Yingying,Guo Lihao,Su Chen,Tang Ning,Zhang Xingmao,Hu Wenwen,Wang Zheng,Zhao Zhenhuan,Zhong Peng,Li Peipei,Du Tao,Haick Hossam,Wu Weiwei
An organic solvent-assisted intercalation and collection (OAIC) approach for preparing Ti 3 C 2 T x (MXene) was developed.
The features of OAIC approach are the low requirement for facility, gram-level preparation with remarkable yield and easy control over the dimension of Ti 3 C 2 T x flakes.
The Ti 3 C 2 T x flakes prepared by OAIC approach showed the outstanding capacitive and rate performance.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Fang Wang,Xianhong Zhang,Le Yang,Dehong Xu,Yuhong Ma,Dong Chen,Li Wang,Changwen Zhao,Wantai Yang
A composite of a core–shell structured nanowires with ZnO as a core and conductive poly(3,4-ethylenedioxythiophene) (PEDOT) as a shell was prepared. At first, the hexagonal ZnO nanowires, with diameter of about 80–100 nm and length 4–5 μm, were fabricated by hydrothermal synthesis process. Then a thick layer of poly(trifluoroethyl methacrylate)- block -poly(sodium styrene sulfonate) (PTFEMA- b -PSSNa) was grafted from the surface of ZnO nanowires via atom transfer free radical polymerization. At last, with the ZnO@PTFEMA- b -PSSNa as a template and the PSSNa chain as the counterion dopant, PEDOT was precipitated onto the surface of the template to form the composite of ZnO@PEDOT/PSSNa. With the evaluation of the EDOT polymerization, the thickness of the PEDOT layer increased steadily. However, as the ratio of EDOT/ZnO was greater than 1:2, the ZnO nanowires templates were dissolved at last and then PEDOT particles were produced due to increasing of the acidity during the oxidation polymerization of EDOT. In this case, the product was the mixture of the nanotubes and particles of PEDOT/PPSNa. The electrochemical capacitances of the composites with different structures were investigated with cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy techniques with three-electrode cell configuration. The maximum specific capacitance of ZnO@PEDOT electrode can reach 101.34 F/g at 20 mV/s.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
IONICS
·
2012
·Vol. 19
·期 5
·757-762
·
IF 1.288
Ran Ying,Yin Zhoulan,Ding Zhiying,Guo Huajun,Yang Jing
A polymer electrolyte based on the blending of poly(vinylidene fluoride-hexafluoropylene) (PVDF-HFP) and hydroxypropyl methyl cellulose (HPMC) was prepared for the first time. The structure and performance of the gel polymer electrolyte were characterized and measured by X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy, electrochemical impedance spectroscopy, linear sweep voltammetry, and by a charge/discharge test. The results show that the gel polymer electrolyte has the best performance when PVDF-HFP/HPMC ratio ( w / w ) is 4:1. At room temperature, the ionic conductivity can reach 0.38 × 10 −3 S cm −1 , the electrochemical stable window is up to 5.0 V (vs. Li/Li + ), and the half cell of Li/GPE/LiMn 2 O 4 shows high-discharge-specific capacity and good cycling performance.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Bin Xiao,Gang Wu,Tongde Wang,Zhengang Wei,Yanwei Sui,Baolong Shen,Jiqiu Qi,Fuxiang Wei,Qingkun Meng,Yaojian Ren,Xiaolan Xue,Junchao Zheng,Jing Mao,Kehua Dai
High entropy oxides (HEOs) have attracted the attention of researchers due to their high theoretical specific capacity and structural stability. However, the effect of elements in HEOs on material properties is unknown. In this work, HEOs (FeNiCrMnZn) 3 O 4 and (FeNiCrMnMg) 3 O 4 were successfully synthesized and used as anode materials for lithium ion batteries . The effects of Zn and Mg on the properties of HEOs were studied from the aspects of crystal structure, micro morphology, and surface valence. Results show that Zn enhances the lithium storage performance of HEOs theoretically, which is verified in the later electrochemical performance tests. (FeNiCrMnZn) 3 O 4 is better than (FeNiCrMnMg) 3 O 4 in all aspects of rate properties, cycle performance, and electrochemical impedance spectroscopy . Therefore, the introduction of electrochemically active metals, such as Zn, can improve the performance of HEOs, thereby providing ideas for the subsequent design and application of HEOs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RARE METALS
·
2019
·Vol. 39
·期 7
·841-849
·
IF 1.785
Zhang Yi-Fei,Zhu Yu-Kun,Lv Chun-Xiao,Lai Shou-Juan,Xu Wen-Jia,Sun Jin,Sun Yuan-Yuan,Yang Dong-Jiang
A heterojunction photoanode of Fe 2 O 3 loaded on a WO 3 film on a fluorine-doped tin oxide substrate (FTO-WO 3 /Fe 2 O 3 ) was prepared via a simple hydrothermal and chemical vapor deposition (CVD) growth method. The photoanode showed higher photoelectrochemical (PEC) water-splitting activity than that of the pristine FTO-WO 3 under simulated sunlight because of the synergistic effect of Fe 2 O 3 and WO 3 . The as-synthesized material was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The photocurrent density was estimated by linear sweep voltammetry and further confirmed using intensity-modulated photocurrent spectra. Experiments demonstrated that the coated Fe 2 O 3 enhanced the separation and migration efficiencies of the photoinduced electrons and holes, improving the PEC water-splitting properties. The FTO-WO 3 /Fe 2 O 3 photoanode showed a 1.25 times enhancement in photocurrent density compared with FTO-WO 3 . This result suggests that facile chemical vapor deposition growth is an effective way to fabricate heterojunctions and improve the properties of WO 3 photoanodes for PEC water-splitting applications.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Wenwen Li,Hongyan Wang,Zhe Sun,Quanping Wu,Song Xue
Cuprous oxide (Cu 2 O) is an attractive photo-electrocatalyst for sustainable hydrogen production . The main issues limiting the use of Cu 2 O as a photocathode are the severe electron-hole recombination and photo-corrosion in aqueous electrolyte . Herein, to address the above issues, amorphous SiO x overlayers have been deposited on the surface of Cu 2 O as a protective cover using a facile dip-coating method. The overall PEC performances have been greatly improved, as evidenced by the increased photocurrent density (3.1 times of bare Cu 2 O) and improved stability (3.8 times of bare Cu 2 O). The structure and PEC characterizations prove that Si has been gradient-doped into the Cu 2 O, leading to a downward band bending from the bulk to the surface region, which promotes the charge separation and transfer efficiently. In addition, the amorphous SiOx layers serve as protection layers and prevent the Cu 2 O from direct contact with the electrolyte, maintaining a high photocurrent density over the stability test. Decoration with Pt catalyst has further boosted the photocurrent density to be 2.8 mA cm −2 at 0 V vs. RHE with better stability, indicating the synergistic effect of SiOx layer and Pt catalyst This work provides a facile strategy to improve the PEC activity and stability of Cu 2 O, which may be extended to other systems with photo-corrosion problems, such as BiVO 4 or ZnO.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2013
·
IF 1.789
Lianyi Shao,Songying Wang,Kaiqiang Wu,Miao Shui,Rui Ma,Dongjie Wang,Nengbing Long,Yuanlong Ren,Jie Shu
Comparison of (BiO) 2 CO 3 to CdCO 3 as anode materials is investigated in this paper. Electrochemical results show that both (BiO) 2 CO 3 and CdCO 3 are electrochemically active materials with high initial capacities of 1080.1 and 1251.1 mAh g −1 , respectively. Ex-situ X-ray diffraction (XRD) results show that the electrochemical reaction mechanisms of CdCO 3 with Li can be associated with the preliminary formation of Cd and Li 2 CO 3 upon the initial lithiation, and then the final formation of LiCd alloy upon further lithiation. In contrast, the electrochemical reaction of (BiO) 2 CO 3 with Li not only results in the formation of Bi and Li 2 CO 3 , but also induces the formation of Li 2 O. Besides, upon further lithiation, the alloying reaction of Bi with Li is a multi-step process to form LiBi, Li x Bi, and finally Li 3 Bi as confirmed by electrochemical behaviors and in-situ XRD technique. Compared with CdCO 3 , (BiO) 2 CO 3 can exhibit better electrochemical properties with a reversible capacity of 155.1 mAh g −1 and a capacity retention of 28.3% after 15 cycles. By introducing carbon black as conductive additive and volume change buffer, the reversible capacity of ball-milled (BiO) 2 CO 3 /C composite can be improved to the value of 297.6 mAh g −1 with a capacity retention of 47.8% after 15 cycles.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2013
·Vol. 1
·期 43
·13648-13654
·
IF 0
Fei-Hu Du,Kai-Xue Wang,Wei Fu,Peng-Fei Gao,Jing-Feng Wang,Jun Yang,Jie-Sheng Chen
A graphene-wrapped silver–porous silicon composite has been prepared and used as the anode material in lithium-ion batteries (LIBs). Porous silicon (pSi) prepared through a magnesiothermic reduction of mesoporous silica MCM-41 was surface-modified by Ag nanoparticles formed via the thermal decomposition of AgNO3 and then graphene nanosheets (GNS) generated through the thermal reduction of graphene oxide. The obtained Ag–pSi/GNS composite exhibits a distinctly high reversible specific capacity, long cycling performance and super rate capability. An initial capacity as high as 3531 mA h g−1 is delivered at 0.1 A g−1, whereas at a current density of 32 A g−1, a specific capacity of 1241 mA h g−1, more than three times higher than the theoretical capacity of the graphite anode, is still retained for 50 cycles. The superior electrochemical performance demonstrates that this Ag–pSi/GNS composite is a promising electrode material for high-performance LIBs.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）