JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Yang Tao,Qing Liu,Yujiao Guo,Mingwu Xiang,Xiaofang Liu,Wei Bai,Junming Guo,Shulei Chou
Electrochemical properties of spinel LiMn 2 O 4 cathode material have been always suffered from Mn dissolution and Jahn-Teller distortion. Herein, various Ni/B dual-doped LiNi 0.08 B x Mn 1.92- x O 4 ( x = 0–0.15) with a truncated octahedral morphology are synthesized via a facile solid-state combustion. The effects of Ni/B co-doping on the morphology, crystal structure, Mn dissolution, Li + diffusion coefficient and activation energy are investigated. Due to the relatively high Ni–O and B–O bond energy than that of Mn–O bond, the structure stability of the LiMn 2 O 4 is enhanced, whilst restraining the Jahn-Teller distortion. The LiNi 0.08 Mn 1.92 O 4 shows (111), (110) and (100) facets. In comparison, the B-doping endows the LiNi 0.08 B x Mn 1.92- x O 4 ( x ≥ 0.02) with (111) and (100) facets. This morphology evolution without (110) facets effectively inhibits the Mn dissolution. Owing to the synergistic merits of Ni/B dual-doping and unique truncated octahedron , the optimized LiNi 0.08 B 0.06 Mn 1.86 O 4 delivers an initial discharge capacity of 113.9 mAh∙g −1 at 1C and maintains a durable cycling life up to 2000 cycles at 5C. Even at 20C, a capacity retention of 86.3% is still obtained after 2000 cycles. Furthermore, a capacity retention of 70.6% can be retained after 500 cycles at 5C and 55 °C. The truncated octahedral LiNi 0.08 B x Mn 1.92- x O 4 with excellent electrochemical performance will be a good candidate for developing long-life lithium-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Lei Huang,Zhihui Yang,Yujun Shen,Peng Wang,Baocheng Song,Yingjie He,Weichun Yang,Haiying Wang,Zhenxing Wang,Yongsheng Chen
Coordination bonds of ligands and metal ions are generally considered for improving agglomeration during the synthesis of metal oxides . However, the strong interactions always limit the performance due to the requirement of additional energy and calcination . A new strategy of synthesizing ZnO particles is proposed through a hydrothermal inducing redox method by using 2-methyl imidazole and Zn(NO 3 ) 2 . In situ direct redox between this organic ligand and NO 3 − in a hydrothermal condition is confirmed radical change instead of the simple coordination between organic ligands with Zn 2+ in traditional method. The directly acquired ZnO particles possessing uniform dumbbell-like morphology have no obvious agglomeration. The yield reaches >95%. In particular, the synthesis mechanism and morphology evolution during the ZnO aggregates growth were carefully explored and proposed. Density functional theory (DFT) and surface energy calculations demonstrated the effects of activity variation of reactive groups and preferred growth surface of ZnO crystals. This work gives new insights into new synthesis strategy of ZnO particles via hydrothermal condition.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2018
·
IF 3.306
Qing Li,Xiaofang Zhu,Ying Zhang,Zhigang Zak Fang,Shili Zheng,Pei Sun,Yang Xia,Ping Li,Yang Zhang,Xing Zou
Hydrogen assisted magnesiothermic reduction (HAMR) of TiO 2 is a promising new process developed recently to produce Ti metal with low cost and less energy consumption. This work focuses on the understanding and optimization of the reduction process to control the quality of the reduced product. TiO 2 precursor particles with different relative densities were prepared, and the effects of the relative densities on reduction by Mg in H 2 were studied. The changes of oxygen contents vs. reduction time at various temperatures were investigated. The phase transformations during the reduction were analyzed both theoretically and experimentally. The relationship between the morphology of the reduced products and the relative densities of the TiO 2 precursors was analyzed by SEM characterization and the likely reason for the morphology evolution was discussed.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
Progress in Natural Science-Materials International
·
2018
·
IF 2.572
Datong Zhang,Zhengping Ding,Shuai Zhao,Ying Yang,Yiming Feng,Lei Xiao,Ran Ji,Libao Chen,Weifeng Wei
Li 2 MnSiO 4 -based cathode materials possess reasonable work potentials and high theoretical capacities, while the practical energy/power densities are constrained by their inferior kinetics of Li + diffusion. In this work, the Pmn2 1 -structure Li 2 Fe x Mn 1-x SiO 4 /C materials were synthesized via a solvothermal method and evaluated as Li-ion cathode materials, with notable morphological evolutions and tunable crystallographic habits observed after solvothermal process. The Li 2 Fe 0.33 Mn 0.67 SiO 4 /C material delivers an initial reversible capacity of 250.2 mAh g −1 at 0.1 C (~ 1.51 Li + insertion/extraction, 1 C = 166 mA g −1 ), excellent high-rate capability (52.2 mAh g −1 at 5 C), and good long-term cyclability (64.6% after 196 cycles at 2 C). The enhanced electrochemical properties are attributed to the boosted ion/electron transports induced by preferred morphological and structural characteristics of Li 2 Fe 0.33 Mn 0.67 SiO 4 /C.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2014
·Vol. 16
·期 46
·10624-10630
·
IF 3.858
Miao Wang,Tongming Sun,Yujun Shi,Guoqing Jiang,Yanfeng Tang
3D hierarchical ZnOHF nanoflowers with mean diameter of 200 nm have been synthesized via a simple template-free hydrothermal route by using (NH4)2SiF6 as the fluoride source. The crystalline phase and morphologies of the as-prepared products have been characterized by XRD, SEM and TEM. The XRD results show that the products are well-crystallized orthorhombic phase of ZnOHF. The SEM and TEM results indicate that the ZnOHF nanoflowers are assembled by numerous nanoflakes with mean thickness of 20 nm. Some factors influencing the morphologies of the ZnOHF nanostructures have been systematically investigated, such as the reaction time, temperature and fluoride source. A growth mechanism is proposed on the basis of a series of time-dependent morphological evolution results. The hierarchical ZnOHF nanoflowers exhibit a high specific surface area up to 97.1919 m2 g−1 with a pore size of 50.098 nm. The as-obtained ZnOHF can be transformed into ZnO nanoflowers by calcination in air at 600 °C. The photocatalytic properties of ZnOHF have been studied by the decomposition of methyl orange (MO) under UV light irradiation. The results indicate that the flower-like ZnO nanostructures are chemically stable, and the efficiency remained almost the same after five times recycling.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Qiang Zhang,Jinxing Chen,Yunyun Xie,Mozhen Wang,Xuewu Ge
Bi 2 WO 6 has great potential applications in the field of photocatalyst due to its excellent visible-light photocatalytic performance. This work studied the detailed morphological evolution of Bi 2 WO 6 particles synthesized in a simple hydrothermal system induced by the stabilizer poly(vinyl pyrrolidone) (PVP). The XRD and HRTEM results show PVP would not change the crystal structure of Bi 2 WO 6 , but the distribution of PVP on the initially formed Bi 2 WO 6 nanosheets will induce the crystal growth, resulting in a distinct morphology evolution of Bi 2 WO 6 with the increase of the concentration of PVP. At the same time, with the increase of the molecular weight of PVP, the morphology of Bi 2 WO 6 varied from simple sheet-like (S-BWO) to some complicated morphology, such as flower-like (F-BWO), red blood cell-like (B-BWO), and square-pillar-like (SP-BWO). The photocatalytic performances of Bi 2 WO 6 with various morphologies on the decomposition of RhB under visible light irradiation reveal that S-BWO has the best photocatalytic performance, while SP-BWO has the worst. This work not only gives the explanation of the inductive effect of PVP molecular chains on the morphological formation of Bi 2 WO 6 particles, but also provides the controllable way to the preparation of Bi 2 WO 6 with various morphologies taking advantage of the stabilizer PVP.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2021
·
IF 3.882
Wei Zhang,Hua Cheng,Rui Pan,Yi Gong,Zhengya Gan,Rui Hu,Jianjun Ding,Xian Zhang,Xingyou Tian
Colloidal molecules (CMs), nonspherical clusters of a small number of particles, can be used as building blocks for self-assembly applications. Here, we propose a novel one pot method for CMs synthesis. First, poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AA)) microgels were prepared by soap-free emulsion polymerization as seed particles, then monomer styrene and cross-linking agent divinylbenzene (DVB) were added, which could be polymerized by the remaining free radicals on the seed surface in situ. P(NIPAM-co-AA)-PS colloidal molecules with a series of morphologies such as popcorn-like, CO2-like, NH3-like, CH4-like and so on could be obtained. The effects of satellite colloid viscosity, interfacial tension, and polymer chain mobility on the number of satellite colloid have been investigated, and the formation mechanism of CMs is proposed based on morphology evolution investigation. Compared with the existing CM synthesis techniques, our method enables fabricating CMs from vinyl monomer in a facile and efficient way, and the scientific finding regarding the CMs formation will guide the CMs fabrication toward salable and reliable direction.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Science
·
2025
·
IF 14.1
Ningyan Cheng,Hongyu Sun,Yevheniy Pivak,Christian H. Liebscher
Copper (Cu)-based nanomaterials are one of the most efficient heterogeneous electrocatalysts for the CO 2 reduction reaction. However, their selectivity and stability are strongly determined by their morphology, crystal structure, composition, grain size, grain boundary density, etc. Hence, gaining quantitative insights into their dynamic evolution under synthesis and/or working conditions is critical for developing optimal Cu-based electrocatalysts and unveiling their structure-property relationship. In this work, the possibility of addressing these issues is demonstrated by integrating in situ liquid phase transmission electron microscopy (LP-TEM) with 4D scanning transmission electron microscopy (4D-STEM). Here, the dynamic morphology and phase evolution of Cu nanoparticles during electrodeposition and electrooxidation processes are revealed in liquid. Virtual imaging and selected area electron diffraction provide novel insights into the evolution of defective nanocrystalline Cu nanoparticles during electrodeposition. It is shown that virtual off-axis dark field imaging can be used to map the distribution of Cu 2 O and Cu within partially oxidized Cu nanoparticles, opening new opportunities for quantitatively probing electrocatalysts under operando conditions.
研究领域:
材料科学
·
电催化
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2020
·Vol. 49
·期 43
·15433-15442
·
IF 4.174
Yini Mao,Zhiyi Wang,Rui Ye,Li Jiang,Shanshan Hu,Jun Yang
Octahedral [CaY]F2 crystals with an average particle size of 1 μm were synthesized via a mild one-step hydrothermal route without employing any surfactants. Various morphologies, including cubes, truncated cubes, truncated octahedrons, and spheres, were achieved via manipulating the amount of EDTA used, and a possible growth mechanism was proposed based on the surface energies of different crystal planes and the influence of the surfactant. XRD, SEM, EDS, TEM, HRTEM, and PL analysis were used to characterize the products. The effects of the morphologies and Li+ doping concentrations on the luminescence intensities of the [CaY]F2:Ce3+/Tb3+ phosphors were explored, and the strongest luminescence intensity is obtained when the sample is cubic with (100) crystal faces and the doping concentration of Li+ is 0.25 mol%. Additionally, multicolor emission (blue → aquamarine blue → green) was obtained from [CaY]F2:Ce3+/Tb3+ phosphors via adjusting the doping concentration of Tb3+, which resulted from the Ce3+ → Tb3+ energy transfer behavior; the energy transfer here happened through a dipole–dipole mechanism. This work may result in the as-synthesized phosphors having great application potential in many optoelectronic device fields, such as in displays and multicolor lighting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Zhihua Li,Yunbin Xiao,Shengyuan Liang,Tongtong Zhang,Yuanyuan Tu,Shudong Lin,Zhenzhu Huang,Liangzhi Hong,Jiwen Hu
Herein, we demonstrate a facile and scalable approach to prepare triple-scale colloidal particles via a one-step dispersion polymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in a toluene/ethanol solvent mixture. The morphologies of the colloidal particles can be readily tuned by adjusting the composition of the binary solvent mixture and other copolymerization parameters. Based on the morphological evolution and size variations of the colloidal particles collected during the one-step dispersion polymerization process, a plausible formation mechanism was proposed for these triple-scale colloidal particles. The addition of toluene not only prolonged the nucleation time by increasing the solvency of the solvent mixtures, but also increased the swelling capability of the growing particles for the glycidyl methacrylate and ethylene glycol dimethacrylate. The formation of triple-scale structure was attributed to the elastic stress of the crosslinked polymer network, which extrudes the swellen monomer and crosslinker. In addition, colloidal particle with various surface roughness were utilized to stabilize Pickering emulsions, and the correlation between particle surface roughness and the properties of Pickering emulsion was also investigated. As the particle surface roughness increase, stable O/W Pickering emulsions with diameters of hundreds of microns were obtained.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 58
·53331-53338
·
IF 3.289
Chuan Ding,Yanwei Zeng,Liangliang Cao,Rongjie Li,Yuan Zhang,Longfei Zhao
Monodisperse MnxFe3−xO4 (x = 0, 0.3, 0.6) polyhedrons enclosed by {100}/{111} facets with different area ratios were synthesized through the thermolysis of Fe(acac)3 and Mn(acac)2 by effectively tuning the Mn/Fe ratio to mediate the adsorption properties of oleic acid (OA) on crystal surfaces after annealing treatment in N2, and studied as high rate (≥1 A g−1) anode materials for lithium ion batteries (LIBs). The electrochemical results show that Mn0.6Fe2.4O4 octahedra possess the best rate cycling performance compared to that of Mn0.3Fe2.7O4 cuboctahedra and Fe3O4 cubes, characterised by a 500th discharge capacity of 803.5 mA h g−1 at 1 A g−1 and a rate capability of 661.5 mA h g−1 when cycled at 4 A g−1, as a result of high electrochemical activity of {111} facets with the highest Fe atom surface density. The present results prove that the substitution of Fe by Mn in the spinel-type anode materials can result in better cycle stability and it would be helpful for the further understanding of Fe3O4 based anode materials and provide a simple and practical route to design high rate anode materials for lithium-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Zengyu You,Yuxuan Su,Yang Yu,Hui Wang,Tian Qin,Fang Zhang,Qianhong Shen,Hui Yang
A novel g-C 3 N 4 nanorod/InVO 4 hollow sphere composite was fabricated through a facile template-free method. The structure-property relationship was analyzed, and the formation mechanism of such structure and morphology was also proposed based on the observation from time-dependent morphology evolvement. The results show that InVO 4 hollow spheres uniformly load on the surface of g-C 3 N 4 nanorod and thus forming the heterojunction with an intimate interface. The bulk g-C 3 N 4 experiences a possible peeling process to form the rod-like structure, during which the mass ratio of InVO 4 and ultraphonic process play a key role. Moreover, bubble-template is believed to determine the formation of InVO 4 hollow sphere. Owing to this unique structure and morphology, the enhanced visible-light photocatalytic activities are achieved because of the synergistic effect of light harvesting, high transfer efficiency and enhanced separation efficiency of photo-generated carriers. And more importantly, this fabrication method combines heterojunction constructing with morphology controlling of g-C 3 N 4 in one step, and thus may supply a new idea for the preparation of other g-C 3 N 4 based composites.
研究领域:
材料科学
·
环境科学
✓ 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）