JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 21
·18360-18369
·
IF 2.22
Wang Mengmeng,Tao Yueming,Zhang Dongyun,Sun Guanghan,Feng Ping,Chang Chengkang
Na 3–2 x Mg x V 2 (PO 4 ) 3 /C (0 ≤ x ≤ 0.2) were synthesized by a sol–gel method. According to X-ray diffraction (XRD) Rietveld refinement and energy dispersive spectroscopy (EDS) mapping results, Mg ions were approved to occupy the Na2 (18e) site in Na 3–2 x Mg x V 2 (PO 4 ) 3 /C for the first time. The amount of Mg substitution in Na 3–2 x Mg x V 2 (PO 4 ) 3 /C was optimized. The specific discharge capacities of Na 2.9 Mg 0.05 V 2 (PO 4 ) 3 /C at 10 C, 20 C, and 30 C were 98.9%, 91.5%, and 76.2% of the value obtained at 1 C, respectively. Na 2.9 Mg 0.05 V 2 (PO 4 ) 3 /C exhibited the highest capacity retention of 80.3% with a discharge capacity of 77.3 mAh·g −1 after 1200 cycles at 10 C. Na 2.9 Mg 0.05 V 2 (PO 4 ) 3 /C exhibited superior rate performance, resulting from a high sodium diffusion coefficient ( D Na ) of 3.91 × 10 –12 cm 2 ·s −1 and the excellent electrical conductivity (5.7 × 10 –2 s·cm −1 ). Combining the X-ray photoelectron spectroscopy (XPS) and Electrochemical impedance spectroscopy (EIS) results, the mechanism of Mg substitution was investigated. Since two Na + were replaced by one Mg 2+ , \({\mathrm{V}}_{\text{Na}}^{^{\prime}}\) was produced to maintain valence equilibrium. This phenomenon benefited Na + migration by broadening the diffusion channel in the structure of Na 3 V 2 (PO 4 ) 3 . According to the EPR results, the signal intensity of Na 2.9 Mg 0.05 V 2 (PO 4 ) 3 /C was much stronger than that of Na 3 V 2 (PO 4 ) 2 /C, thus confirming the existence of \({\mathrm{V}}_{\text{Na}}^{\mathrm{^{\prime}}}\) after Mg substitution. When the amount of Mg substitution was further increased to 0.1, the D Na decreased because of the small radius of Mg 2+ , which led to severe lattice distortion and volumetric shrinkage of the unit cell.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 19
·12219-12225
·
IF 4.036
Yang Song,Yuchong Kang,Wei Ma,Haibo Li
Herein, a facile one-step method is developed to in situ prepare crystalline anatase and rutile TiO2 nanocrystals on Ti3C2Tx by regulating the metastable Ti ions. The combination of TiO2 nanocrystals and Ti3C2Tx not only introduces extensive accessible sites for Na+ storage, but also promotes the charge transport by efficiently relieving the collapse of Ti3C2Tx. Compared with pristine Ti3C2Tx, the optimized TiO2/Ti3C2Tx hybrid electrode (anatase/rutile-TiO2/Ti3C2Tx, A/R-TiO2/Ti3C2Tx) exhibits a desirable specific surface area (22.5 m2 g−1), an ultralow charge transfer resistance (42.46 Ω) and excellent ion diffusion (4.01 × 10−14). Remarkably, rich oxygen vacancies are produced on TiO2/Ti3C2Tx which is beneficial to enhance the insertion/de-insertion of Na+ during the charge/discharge process. As a result, the A/R-TiO2/Ti3C2Tx delivers a high average capacity of 205.4 mA h g−1 at 100 mA g−1 and a desirable capacitance retention rate of 84.7% can be achieved after 600 cycles at 500 mA g−1.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Jiaming Hu,Shuai Zhang,Chen Feng,Shanggeng Li,Longfei Zhang,Jiajun Ma,Qiang Yin
In this work, an efficient Fe 3+ adsorbent was synthesized by using the tryptamine and sodium carboxymethyl cellulose (CMC-Na) modified polyacrylamide gel. The functional monomers synthesized by the reaction of tryptamine and methacrylic acid chloride were doped into the composition, and CMC-Na participated in the formation of the gel network. By changing different conditions, the optimal use conditions of the gel were explored. The Langmuir and Freundlich isotherm models were used to discuss the adsorption behavior. According to the fitting results, the Freundlich model was more suitable for explaining the adsorption of Fe 3+ by gels. The feasibility of its adsorption process was confirmed by the study of its kinetics and thermodynamics. As an adsorbent, tryptamine CMC-Na modified polyacrylamide gel has excellent ability to remove Fe 3+ from aqueous solutions. The maximum adsorption capacity of tryptamine and CMC-Na modified polyacrylamide gel for Fe 3+ reached 127.5 mg g −1 .
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
FirePhysChem
·
2023
·
IF 0
Xinyi Li,Yuangang Xu,Jianxin Zhou,Tianyang Hou,Ze Xu,Pengcheng Wang,Ming Lu
As an important intermediate in the synthesis of most energetic pentazole compounds, the reaction system of sodium pentazole is complex and has many by-products, but there is no suitable HPLC analysis method. Based on the study of ultraviolet absorption peak of sodium pentazole aqueous solution, the HPLC purity analysis method of sodium pentazole was successfully established and its sensitivity, accuracy and repeatability were verified. When the detection wavelength was 192 nm, the chromatographic column was Agilent WondaSil C18 Superb (4.6 × 250 mm, 5 μm), the mobile phase was 95% water and 5% acetonitrile mixed solution, the flow rate was 0.8 ml/min, the analysis time was 8 min, the sample size was 1 μL and the column temperature was 40 °C, a liquid phase map of sodium pentazole was obtained. The analysis results showed that the retention time of pentazole sodium was 3.76 min, and showed a good linear relationship in the range of 0.3068–0.3288 g/L. The linear equation is y = -217447.64+835837.85 x , the correlation coefficient R 2 is 0.99997, and it has good sensitivity, accuracy and repeatability. In addition, three by-products from the synthesis of sodium pentazole were simply separated.
研究领域:
分析化学
·
有机合成
✓ 已验证
DOI
COMPOSITES COMMUNICATIONS
·
2021
·
IF 6.617
Yingjuan Sun,Jiefeng Zheng,Yang Yang,Jianhao Zhao,Jianhua Rong,Hongyan Li,Li Niu
We reports an all-conductive polymers composite with cross-linking network structures composed of porous polyaniline (PANi) and PEDOT:PSS. This composite with unique structures and morphological properties has the ability to be utilized as cathode for sodium ion batteries (SIBs). Specifically, the cathode delivers a high reversible capacity of 81.9 mA h g −1 at a current density of 100 mA g −1 and represents outstanding cycle stability. Remarkably, the PANi-PEDOT cathode exhibits a high performance compared with state of the art performance of cathode materials for SIBs, for instance, Na 2 Fe 2 (SO 4 ) 3 , Na 0·6 Cr 0·6 Ti 0·4 O 2 and Na 2 MnP 2 O 7 . Moreover, the kinetics analysis of cyclic voltammetry represents predominant capacitive process, which plays dominant roles in charge storage. These conductive cross-linking networks structures and high stability endow the cathode good electrical conductivity and play important roles in the cycling stability of the Na ion cathode, thus promoting the electrochemical performances of the cathode, offering a great promise in SIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Chenglei Qin,Liuzhang Ouyang,Hui Wang,Jiangwen Liu,Huaiyu Shao,Min Zhu
Sodium borohydride (NaBH 4 ) is considered to be an excellent hydrogen-generation material via hydrolysis. However, it remains challenge to regenerate it after hydrolysis in practical applications. Therefore, a low-cost regeneration method from hydrolysis by-products for recycling is the key issue. In this study, NaBH 4 was successfully regenerated by direct high-energy ball milling of magnesium alloy (Mg 17 Al 12 ) and hydrolysis by-product NaBO 2 ·2H 2 O with addition of a small amount of NaH. Notably, unlike traditional method, here there is no need of adding extra hydrogen and the H − in the regenerated NaBH 4 is mainly from the H + in the coordinated water. It was found that through adding a small amount of NaH, the highest yield may reach 57% after optimizing the regeneration process. In addition, it is the first time we found that not only Mg can participate in the reaction, but also Al; and the addition of NaH can promote the reaction. Furthermore, the regeneration mechanism of NaBH 4 was analyzed and the transition pattern [B(OH) 4 ] − /[BH 3 (OH)] − /[BH 4 ] − was successfully observed during the regeneration process. It is worth emphasizing that NaBH 4 can be regenerated through ball milling method, which is energy-saving and suitable for up-scaling in the future.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Nano Energy
·
2018
·
IF 13.12
Zhi-Hao Zhao,Xu-Dong Hu,Hongqiang Wang,Meng-Yang Ye,Zhi-Yuan Sang,Hui-Ming Ji,Xiao-Lei Li,Yejing Dai
Rational design of electrode materials for sodium-ion batteries with high flexibility is still challenging. Here, superelastic 3D few-layer MoS 2 /carbon framework heterogeneous electrodes (abbreviated as, MoS 2 @C F ) are fabricated by a simple vacuum infiltration and heating process. The interconnected ultrathin MoS 2 network filled with carbon framework forms a 3D heterogeneous network with hierarchical pore structure . The unique structure of the electrodes results in excellent mechanical and electrochemical performances. The MoS 2 @C F electrodes exhibit superior elasticity and recoverability. After 180° bending repeatedly, the electrodes still can recover their initial sizes. Moreover, the electrodes show outstanding cycling stabilities with high reversible capacities reaching up 240 mA h g −1 after 500 cycles at 1 A g −1 (capacity retention of ~ 99%). Full-cells assembled with MoS 2 @C F anodes and Na 3 V 2 (PO 4 ) 3 cathodes show high reversible capacity (~ 252 mA h g −1 at 0.5 A g −1 ). Overall, the superior mechanical properties and high electrochemical performances indicate the promising potential of MoS 2 @C F electrodes in large-scale flexible sodium-ion storage devices.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2018
·Vol. 166
·期 3
·A5075
·
IF 3.662
Bizhe Su,Jiaolong Zhang,Manabu Fujita,Wenchong Zhou,Patrick H.-L. Sit,Denis Y. W. Yu
Recent experimental and theoretical studies on the family of Li-rich layered materials show that they can deliver much higher capacities than traditional Li-transitional metal oxides. This also leads to great interests in Na-rich layered oxides as alternative positive electrode materials for sodium-ion batteries for large-scale energy storage. Herein, we report a Na-rich material, Na2SeO3 with an unconventional layered structure as a positive electrode material in NIBs for the first time. This material can deliver a discharge capacity of 232 mAh g−1 after activation, one of the highest capacities from sodium-based positive electrode materials. X-ray photoelectron spectroscopy indicates the oxidation state of selenium remains unchanged during the charge process. Theoretical simulation shows that after removal of Na, spin is situated around oxygen atoms near the Na vacancy, and the projected density of state of oxygen electron is close to the Fermi level. These suggest the involvement of oxygen during charge-discharge. This work will propel new searches of high-capacity sodium-based positive electrode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2017
·
IF 4.811
Mingliang Pei,Xu Jia,Xubo Zhao,Jiagen Li,Peng Liu
Alginate-based cancer-associated, stimuli-driven and turn-on theranostic prodrug nanogels were designed for the tumor diagnosis and chemotherapy, by crosslinking the folate-terminated poly(ethylene glycol) (FA-PEG-NH 2 ) and rhodamine B (RhB)-terminated poly(ethylene glycol) (RhB-PEG-NH 2 ) modified oxidized alginate (OAL- g -PEG-FA/RhB) with cystamine (Cys), followed covalent conjugation of doxorubicin (DOX) via acid-labile Schiff base bond. Owing to the surface folic acid (FA) groups, disulfide crosslinking structure and Schiff base conjugation for DOX , the folate receptor (FR)-mediated targeting and pH/reduction dual responsive intracellular triggered release of DOX was achieved. The cytotoxicity and cellular uptake results clearly illustrated that most DOX was released and accumulated in the cell nuclei and killed the cancer cells efficaciously, due to the desirable targeting intracellular triggered release. Furthermore, the theranostic nanogels could be used for the real-time and noninvasive location tracking to cancer cells, owing to the pH-modulated fluorescence property of the pendant RhB groups.
研究领域:
药剂学
·
肿瘤学
·
生物医学工程
✓ 已验证
DOI
高影响因子
Materials Today Sustainability
·
2022
·
IF 7.244
J. Liang,Z. Wang,Q. Ye,L. Qiao,H. Jiang,Y. Guo,Z. Fan
Melt-blown fabric masks have the drawbacks of the supply-demand imbalance, the risks of respirable infection, and environmental pollution . Therefore, it is urgently needed to exploit a new mask material with excellent air-filtration, antimicrobial, and degradable properties. In this study, a new sodium alginate (SA)/nanosilver composite mask intermediate filter layer (named as SAg air filter) is prepared by a simple and quantifiable pumping-injecting method to substitute the traditional melt-blown fabric. Subsequently, the prepared SAg air filter is softened with glycerol solution to improve the flexibility. Compared with the intermediate filter layer of the melt-blown fabric mask, the SAg air filter has more excellent performances, such as environmental friendliness, degradability , large-scale preparation, stable and long-lasting air filtration , good impermeability, as well as suitable breathability. What's more, the air filter combines physical and mechanical filtration, Coulomb adsorption of nano-silver, and antimicrobial air purification through the SAg aerogel network to ensure more comprehensive air purification and filtration. The novel SAg air filter will have a broad application prospect in the mask market, and eventually extend the new application of SA aerogel in the air filtration field.
研究领域:
材料科学
·
医学
·
环境科学
✓ 已验证
DOI
高影响因子
Food Science & Nutrition
·
2022
·Vol. 10
·期 9
·3098-3105
·
IF 3.553
Yongmin Wu,Yi Wu,Peng Han,Jiangqi Xu,Xiaobo Liang
The effects of edible coatings based on sodium alginate with ʻBaozhuʼ pear chitinase on the quality of cherry tomatoes during refrigerated storage were evaluated. Cherry tomatoes inoculated with Fusarium oxysporum were coated and stored up to 21 days. All coatings with the chitinase significantly reduced F . oxysporum proliferation on cherry tomatoes during storage and extended the shelf life of cherry tomatoes effectively ( p < .05). Results showed that alginate coatings with the chitinase could prevent weight loss, maintain firmness, and slow down the changes of titratable acidity and vitamin C ( p < .05) in a dose-dependent manner. However, no significant differences were observed between T3 (1% alginate/0.15% ʻBaozhuʼ pear chitinase/1% glycerin) and T4 (1% sodium alginate/0.3% ʻBaozhuʼ pear chitinase/1% glycerin) ( p > .05). Overall, alginate coating with 0.15% ʻBaozhuʼ pear chitinase could be a promising method to maintain the quality of cherry tomatoes.
研究领域:
食品科学
·
植物病理学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2021
·Vol. 50
·期 4
·1949-1954
·
IF 1.938
Zhang Dunpu,Zhen Yue,Chang Qing,Zhang Hui
Highly crystalline β-NaLuF 4 :Ln 3+ microstructures were successfully prepared via a mixed NaCl-KCl flux cooling approach. The chemical reaction process and the formation mechanism have been carefully investigated by XRD, SEM, TEM and PL characterizations. Interestingly, as the reaction time is prolonged, the crystalline structure of NaLuF 4 changes from α-phase to β-phase, while the granule shape transfers from nanoparticles to solid microsheets then to porous microsheets. By altering the kinds of doped lanthanide ions, upconverting and downconverting luminescence with multi-colour outputs (red, green and blue) can be realized in β-NaLuF 4 :Ln 3+ (Ln = Yb, Er, Tm, Ce, Tb and Eu). This strategy is not only expected to meet the ever-increasing commercial demand, but also offers an alternative in synthesizing rare earth fluorides.
研究领域:
材料科学
·
光学
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）