APPLIED CLAY SCIENCE
·
2020
·
IF 4.605
Sheng Wang,Hengdong Ren,Wei Lian,Jiangzhe Wang,Yan Zhao,Yin Liu,Tianshu Zhang,Ling Bing Kong
The effect of ball-to-powder weight ratio on the crystal composition, microscopic morphology and pore structure of palygorskite was systematically studied by using the conventional wet ball milling process. The quartz can be effectively separated from palygorskite through low-speed centrifugal treatment in aqueous solutions, while the strength of ball milling has a significant influence on disaggregation degree of the crystal bundles. When the ratio is 1:2, the rod crystal bundles are well dissociated, while preserving the inherent aspect ratio of the nanofibers. After the treatment, the specific surface area, micropore volume and micropore area are increased from 206.87 m 2 /g, 0.0347 cm 3 /g and 76.07 m 2 /g to 255.03 m 2 /g, 0.0502 cm 3 /g and 109.42 m 2 /g, respectively. For the first time, the purified palygorskite was used as a template to prepare palygorskite/Fe 3 O 4 nanocomposite using by hydrothermal method , for microwave absorbing applications. As expected, the introduction of palygorskite can effectively prevent the aggregation of the Fe 3 O 4 magnetic particles. Meanwhile, the specific surface area of the composite is enlarged from 10.29 m 2 /g to 40.73 m 2 /g, as the weight ratio of Fe 3 O 4 and palygorskite is 2:1, thus leading to enriched interface polarizations and hence resulting in a maximum reflection loss (RL) of −40.41 dB at 4.80 GHz, with effective absorption frequency that can be adjusted over 2–18 GHz by controlling thickness of the composite.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2015
·
IF 2.999
Yuexin Wang,Yanhua Song,Xiuqing Zhou,Keyan Zheng,Ye Sheng,Pingchuan Ma,Bowen Zhang,Meiqi Chang,Haifeng Zou
Uniform Lu 2 (C 4 H 4 O 6 ) 3 ·6H 2 O cauliflower-like microspheres have been synthesized via a direct precipitation method at room temperature, without any templates and catalysts. The solvent-dependent morphological evolution and the formation mechanism of the Lu 2 (C 4 H 4 O 6 ) 3 ·6H 2 O cauliflower-like microspheres were investigated in detail. Furthermore, Eu 3+ /Tb 3+ -doped Lu 2 O 3 inherited their parents' morphology were obtained through a direct annealing process. The Lu 2 (C 4 H 4 O 6 ) 3 ·6H 2 O:Eu 3+ , Lu 2 O 3 :Eu 3+ exhibit strong red emission corresponding to the 5 D 0 - 7 F j transition of the Eu 3+ ions. The Lu 2 (C 4 H 4 O 6 ) 3 ·6H 2 O:Tb 3+ , Lu 2 O 3 :Tb 3+ exhibit strong green emission corresponding to the 5 D 4 - 7 F j transition of the Tb 3+ ions under UV light excitation. The samples may have potential applications in the fields, such as light-emitting phosphors, advanced flat panel displays, or biological labeling.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 3
·613
·
IF 5.3
Jiahao Qiu,Xingzhong Guo,Wei Lei,Ronghua Ding,Yun Zhang,Hui Yang
Cellulose aerogels are the latest generation of aerogels and have also received extensive attention due to their renewable and biocompatible properties. Herein, cellulose aerogel was facilely prepared by using NaOH/urea solution as solvent, raising the temperature to control gelation and drying wet gel sequentially. With NaOH/urea solution as solvent, the cellulose concentration has an important impact on the micromorphology of cellulose aerogels, while the aging time rarely affects the micromorphology. The appropriate solvent and drying method allow the formation of different cellulose crystalline structures. Different from the Cellulose Ⅰ crystalline structure of raw cellulose powder, the cellulose phase of as-prepared cellulose aerogels belongs to the Cellulose Ⅱ crystalline structure, and to some extent the pyrolysis temperature is also lower than that of raw cellulose powder. The resultant cellulose aerogel prepared by using NaOH/urea solution as solvent and freeze-drying has a uniform macroporous structure with a macropore size of 1~3 µm.Keywords:cellulose aerogels;sol-gel method;temperature control;micromorphology
研究领域:
材料科学
·
生物材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Alan Meng,Tianqi Huang,Huanyu Li,He Cheng,Yusheng Lin,Jian Zhao,Zhenjiang Li
Creating rich vacancies and designing distinct micro-morphology are considered as effective strategies for boosting the electrochemical performances of sodium ion battery (SIB) electrode materials . In this paper, a variety of MoS 2 nanostructures with different sulfur vacancies concentration and morphologies are successfully constructed by a hydrothermal method combined with various-temperature calcination treatment in a Ar/H 2 mixed atmosphere. Employed as a free-standing anode for SIBs, the flower-like MoS 2-x microspheres assembled by the intertwined nanosheet arrays (MoS 2-x -800) delivers highest specific capacity of 525.3 mAh g −1 and rate capability, as well as extraordinarily stable cycle life with almost no loss of capacity after 420 cycles. The favorable sodium storage properties are mainly ascribed to the cooperated effects of superior intrinsic conductivity and richer active sites generated by sulfur vacancies , and numerous interspace achieved by the intersection of neighbouring nanosheets. Meanwhile, through ex situ analyses, the reversible charge/discharge mechanism of the obtained MoS 2-x -800 is revealed reasonably. This work not only brings new insights into the design of high-performance electrode materials for SIBs, but also makes a great step forward in the practical applications of transition metal sulfides in energy storage systems.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 38
·31934-31946
·
IF 3.289
Wei-Wei Wang,Long Jiang,Wu-Yang Ren,Chun-Mei Zhang,Chang-Zhen Man,Thien-Phap Nguyen,Yi Dan
In this paper a series of di-block copolymers of L-lactide and (meth)acrylate [(M)A, representing methyl methacrylate, tert-butyl acrylate and 2-ethylhexyl acrylate] were synthesized by varying the molecular weight of the polylactide (PLLA) macroinitiator and the structure of the (meth)acrylate monomers. The glass transition temperature, crystallinity and thermal stability of copolymers with different poly(meth)acrylate [P(M)A] blocks were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results indicated that the glass transition temperature of the copolymers could be tuned by changing the chain structure and chain length of the P(M)A blocks. Besides, the crystallization of the copolymers was inhibited by the introduction of P(M)A blocks, and the toughness of the copolymers could be tuned. It is noted that the thermal stability of the copolymers depended on the type of P(M)A blocks and the PLLA/P(M)A blocks ratio. Furthermore, the microphase separation of copolymers in thin films was observed by atomic force microscopy (AFM) and scanning electron microscopy (SEM), and the results showed that the composition of copolymers significantly affected the surface morphology of the block copolymer thin films.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2022
·Vol. 128
·期 11
·1-10
·
IF 2.983
Cui Yongbao,Yan Tianxiang,Wang Zhaohui,Sun Haochen,Lei Xiuyun,Yan Shiguang,Fang Liang,Liu Laijun
(1 − x )K 0.5 Na 0.5 NbO 3 – x La(Zn 0.5 Zr 0.5 )O 3 [(1 − x )KNN– x LZZ, x = 0.005, 0.010, 0.015, 0.020] ceramics were synthesized to fulfill the application requirement of high-temperature ceramic capacitors. The influence of LZZ content on the phase structure, microstructure morphology, dielectric and conductivity behaviors of this system was conducted. An orthorhombic phase for 0.005 ≤ x ≤ 0.010 and an orthorhombic-tetragonal coexisting phase for 0.015 ≤ x ≤ 0.020 were determined by the X-ray diffraction, Rietveld refinement, and dielectric spectra. The ceramic with x = 0.015 exhibits an ultrahigh and stable permittivity ( ε' ~ 1892, ± 15% variation) and a low dielectric loss (tan δ ≤ 0.05) in a wide temperature region of 82–382 °C owing to the composition heterogeneity-induced shoulder-like peak and diffuse phase transition from tetragonal to cubic. The activation energies from the high-temperature dielectric relaxation and conductivity behaviors initially enhance greatly and then increase slowly, which could be related to the synergy effect of decreased oxygen vacancies and microstructure morphology evolution.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Zhenzhong Hou,Hai Lu,Qinghao Yang,Qiuli Zhao,Jun Liu
Porous polypyrrole (PPy) free-standing films are prepared by the self-assembly of a mixture of two long-chain surfactants (Span80 and OP10) via interfacial polymerization. The micromorphology of synthesized PPy is investigated by scanning electron microscope (SEM), while its electrochemical performance is evaluated by the means of cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). The results show that the morphology of obtained PPy can be controlled from ruptured vesicle-like structure to network-like structure, then to coral-like structure by tuning the HLB (Hydrophile-Lipophilic Balance) value of mixed surfactant in the synthetic process, and the HLB value plays a crucial role in improving the electrochemical performances of as-prepared PPy. Particularly, interconnected PPy network bonded with ∼800 nm PPy particles could be perfectly prepared at HLB value of 10.4. Because of its larger active surface area , more excellent conductivity and higher porosity than other samples, the maximum specific capacitance and energy density are obtained up to 286 F g −1 and 39.7 Wh kg −1 , respectively, at a current density of 0.5 A g −1 . Furthermore, 88.6% of the initial specific capacitance is retained even after 2000 cycles.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Dong Wang,Xianrui Bai,Jianzong Man,Hua Yang,Gaohui Du,Zhaoyang Wang,Pengfang Zhang,Fanghui Du,Wenjing Shi
Advanced flexible CoSe 2 @carbon fibers (CoSe 2 @CNFs) were synthesized through electrospinning and sintering processes, with the aim of being applied to high rate and long cycle stability of sodium ion batteries (SIBs) and lithium‑sulfur batteries (LSBs). CNFs interconnect ultrafine CoSe 2 particles to form a coating structure, and the fibers intertwine to create a self-standing three-dimensional network. This not only helps to store electrons in electrochemical reactions but also facilitates the adsorption and desorption of Na + /S species. Therefore, when directly used as an anode for SIBs, the electrode has a reversible capacity of 202.1 mAh g −1 after 3000 cycles at a current density of 10 Ag −1 . The microstructure changes of CoSe 2 during the charging and discharging process were investigated in detail by TEM, and the results showed that the crystal form of CoSe 2 changed from long range-order transforms into short-range disorder after sodiated. In addition, the electrocatalytic advantages of flexible electrodes as catalysts for lithium polysulfides can be easily demonstrated through catalytic experiments. Leveraging the morphology and inherent advantages of CoSe 2 , the flexible CoSe 2 @CNFs electrode demonstrates a reversible capacity of 566.8 mAh g −1 at 5 C after 1500 cycles. Most importantly, the morphology of CoSe 2 after the electrochemical reaction was carefully investigated, demonstrating its consistency before and after the electrocatalytic reaction. Flexible CoSe 2 @CNFs provide diversity for the development of high rate performance SIBs and long cycle stability LSBs, and promote a deeper understanding of their morphological evolution during electrochemical reactions.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2016
·Vol. 16
·期 1
·588-594
·
IF 1.338
Xu Lihuan,Huang Qifei,Su Chang,Zhu Xiaogang,He Huihui,Zhang Cheng
In this paper, LiFePO4 samples were synthesized in the water/ethanol mixture solvent environment with different volume ratio of water/ethanol, and the effects of different solvent environment (different water/ethanol ratio) on the morphology, the crystal structure and the
cell performances were studied in detail. The prepared samples were investigated comparatively by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and various electrochemical testing techniques. The results showed that the water/ethanol ratio
seriously affected the crystal structure, the micro-morphologies and the electrochemical properties of the resulting LiFePO4-based electro-active material. And the growth of [010] direction of LiFePO4 crystal was limited with the increase of alcohol proportion in the
mixed solvent, while the size of obtained particles became small in the same process. In addition, LiFePO4 samples obtained at high alcohol content presented the improved specific capacity and rate performances. Specially, the LFP-D electrode displayed the discharge capacity of
153.2 mAh·g−1 at the rate of 0.1 C and the improved rate performance of 150.6, 143.6, 133.8, 121.4, 99.5 and 78.2 mAh·g−1 at 0.2 C, 0.5 C, 1 C, 2 C, 5 C and 10 C, respectively.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Yunji Xie,Su Li,Jinhui Pang,Zhenhua Jiang
The piperidinium cation exhibited a substantial impact on the improvement of alkaline stability of anion exchange membranes (AEMs), yet the research regarding the micro-block polymer AEMs modified with it has not been conducted. Herein, we report two series of micro-block poly(arylene ether sulfone)s containing densely benzyl- N -methylpiperidinium (TTP- n -PIPPES) and benzyl-trimethyl-ammonium (TTP- n -QAPES) functionalized units for AMEs, respectively, where the n represents the molar ratio of monomer containing tri-tetraphenyl to the employed bisphenol monomers. The content and arrangement of the two types of cations in both polymer backbones were the same. The hydrophilic phases of TTP- n -PIPPES membranes exhibited isolated island states, wrapped with coherent hydrophobic phases. While the TTP- n -QAPES membranes formed continuous hydrophilic channels but fragmented hydrophobic phases. The discrepancy in the microscopic morphology of membranes and the intrinsic nature of cations thus rendered two types of AEMs with different advantages in macroscopic properties. The TTP- n -PIPPES membranes performed better dimensional stability and alkaline stability (low temperature). In contrast, the preferable capabilities of TTP- n -QAPES membranes were water affinity, hydroxide conductivity, and alkaline stability (high temperature). For instance, the TTP-18.2-PIPPES membrane was 11.7%, 11.4%, and 27.4% lower than the TTP-18.2-QAPES membrane at 80 °C in terms of dimensional change, water uptake, and hydroxide conductivity, respectively.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Fei Xiao,Hongxia Zhang
Improving the hydrolysis reaction properties of aluminum to prepare renewable and environmentally friendly hydrogen is of great interest for the application of mobile hydrogen sources . Here, a series of poly(tetrafluoroethylene)-based activated aluminum composites were prepared, and their microstructures and hydrogen generation properties were investigated in detail. The results show that PTFE can effectively increase the hydrolysis reaction rate of activated aluminum composites. The sample Al–8Bi-2PTFE exhibits the fastest hydrolysis reaction rate. Through observing the microscopic morphology of the hydrolyzed products of Al–8Bi-2PTFE at different reaction times, the catalytic role of PTFE in the hydrolysis reaction of the composite was proved. PTFE can accelerate the rupture of the particles of Al–8Bi-2PTFE during the hydrolysis reaction, thereby accelerating the hydrolysis reaction rate of aluminum.
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 MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 26
·20532-20543
·
IF 2.779
Liu Xinglong,She Xinyao,Jia Quanliang,Xu Dong,Li Jiamao
This paper reports a controllable synthesis of 6Ca 0.61 Nd 0.26 TiO 3 –4Nd(Zn 1/2 Ti 1/2 )O 3 (6CNT–4NCT) nanopowders by the citrate precursor method. The structural and micromorphological features of the nanoparticles were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques, respectively. The sintering behavior and microwave dielectric characteristics were studied in the form of the bulk ceramics derived from the as-synthesized powders. The results showed the direct formation of single phase 6CNT–4NCT without any impurity after calcining the citrate precursor at 700 °C. Moreover, the as-synthesized powder had good dispersion and high sinterability, which were beneficial for sintering of ceramics. The 6CNT–4NCT ceramics were well sintered at 1220 °C and possessed attractive dielectric properties: ε r = 58.2, Q × f = 57,150 GHz, and τ f = + 1.7 ppm/°C.
研究领域:
材料科学
·
陶瓷学
·
电子材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）