Small Methods
·
2018
·Vol. 3
·期 4
·1800111
·
IF 0
Yuruo Qi,Junmei Zhao,Chao Yang,Huizhou Liu,Yong-Sheng Hu
Sodium vanadium fluorophosphate, Na 3 (VO 1− x PO 4 ) 2 F 1+2 x (0 ≤ x ≤ 1), is proved to be a series of very promising cathode materials for Na-ion batteries, owing to the high operating voltage and structural stability. However, the selective preparation of phase-pure Na 3 (VO 1− x PO 4 ) 2 F 1+2 x (0 ≤ x ≤ 1) with outstanding electrochemical performance still remains a big challenge. Moreover, there are lots of discrepancies concerning the Na-storage properties, including a diversity of voltage profiles and capacities reported, based on the variety of synthetic methods. Herein, a comprehensive investigation is conducted about the fabrication of phase-pure Na 3 (VO 1− x PO 4 ) 2 F 1+2 x (0 ≤ x ≤ 1) by employing different starting materials and corresponding synthetic conditions, based on a facile low-temperature hydrothermal strategy. Results show that the pH in the reaction system may be of vital importance for the successful preparation of Na 3 (VO 1− x PO 4 ) 2 F 1+2 x (0 ≤ x ≤ 1) with special microarchitecture. Furthermore, it is found that NaH 2 PO 4 ·2H 2 O is the most appropriate phosphorus source, while VCl 3 , VOSO 4 · x H 2 O, and NH 4 VO 3 are the best choices of vanadium sources to prepare Na 3 (VO 1− x PO 4 ) 2 F 1+2 x (0 ≤ x ≤ 1) with superior Na-storage performance. This is the first time that the underlying correlations between the starting materials and the Na-storage performance, are investigated and further that guidance for the selective synthesis of phase-pure Na 3 (VO 1− x PO 4 ) 2 F 1+2 x (0 ≤ x ≤ 1) with superior performance is provided.
研究领域:
材料科学
·
电化学
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DOI
Laser & Photonics Reviews
·
2023
·Vol. 18
·期 3
·2301039
·
IF 11
Qianxi Pang,Yichao Wang,Liqing Yan,Ge Zhu,Sai Xu,Jinsu Zhang,Xizhen Zhang,Yongze Cao,Baojiu Chen
Technological progress has promoted the development of ultra-wide near-infrared (NIR) luminescent materials as a new NIR light source. The ultra-wide near-infrared (NIR) emission in Na(Al,Ga) 11 O 17 :xCr 3+ (NAGO:xCr 3+ ) phosphors is achieved by constructing unique Cr 3+ -Cr 3+ ion pair confined structure. The Cr 3+ -Cr 3+ ion pairs can be observed at a low concentration of Cr 3+ ions(x = 0.04), the increase of Ga 3+ ion would promote the formation of Cr 3+ -Cr 3+ ion pairs, thereby effectively enhancing the energy migration process from high-energy Cr 3+ ions to low-energy Cr 3+ ones. Herein, the full width at half maximum can be finely adjusted in a wide range from 17 to 223 nm, while the emission peaks can shift from 704 to 860 nm. NAGO:xCr 3+ exhibits the longest-wavelength emission in the known Cr 3+ -doped galliates and aluminates phosphors. The study further reveals the inherent mechanism of affect on the photoluminescence properties for Cr 3+ -Cr 3+ ion pairs. The quantum efficiency of optimal NaAl 11 O 17 :0.004Cr 3+ (sharp emission) and NaGa 11 O 17 :0.02Cr 3+ (ultra-wide emission) samples reaches 87.6% and 46.6% with high thermal stability (84.47% and 67.52%@150 °C), respectively. The comprehensive properties are excellent among known phosphors with similar property. Multifunctional applications of NAGO:xCr 3+ in agricultural production, quality inspection, and imaging fields are also demonstrated.
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DOI
高影响因子
Frontiers in Chemistry
·
2019
·
IF 3.782
Hao Guo,Yong Hu,Xiaoping Zhang,Rongliang Zhang,Dong Hou,Yulei Sui,Ling Wu
In this paper, we report a facile one-step hydrothermal method to synthesize tetragonal Na3V2(PO4)2F3@C particles which are connected by carbon nanotubes (CNTs) networks, using water as hydrothermal solvents. In this strategy, the reduction and crystallization of materials are carried out in the hydrothermal process (180°C, 12 h), no additional heat treatment is required. The well-crystallized Na3V2(PO4)2F3 tetragonal grains (5–10 μm) are coated with amorphous nano-carbon and connected by highly conductive CNTs. The addition of CNTs can not only improve the conductivity of materials but also effectively inhibit the Na3V2(PO4)2F3 grains over growth. The Na3V2(PO4)2F3@C/CNTs composite possesses very flat charge/discharge platforms of 3.6 and 4.1 V. The sample exhibits an initial discharge specific capacity of 120.2 and 74.3 mAh g−1 at 0.1 and 10 C rate, respectively, and shows excellent cyclical stability. The composite owns excellent electrochemical performances owing to the three-dimensional highly conductive network which is co-constructed by the CNTs and nano-carbon coating layer.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
无机化学
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DOI
高影响因子
SOLID STATE IONICS
·
2020
·
IF 3.107
Jian Liu,Ying-Ge Xu,Ling-Bin Kong
Sodium-ion batteries (SIBs) and Sodium-ion capacitors (SICs) have great promise for large-scale energy storage. However, the mismatch of electrode kinetics and charge-storage capacity between anode and cathode materials remains a challenge. Here three-dimensional self-assembled MoS 2 /SnS 2 -reduced graphene oxide (MoS 2 /SnS 2 -RGO) anode material with fast Na-ion diffusion rate and pseudocapacitive charge storage has been successfully prepared via a facile hydrothermal method . With this particular structure, the Na-ion diffusion coefficient of MoS 2 /SnS 2 -RGO calculated by GITT achieves 5.53 × 10 −7 cm 2 s −1 during the desodiation process, which effectively improves the reaction kinetics for anode material. When tested against metal sodium in the potential window of 0.01–3.00 V, the optimized MoS 2 /SnS 2 -RGO delivers an excellent reversible capacity of 818.9 mA h g −1 at a specific current of 100 mA g −1 after 100 cycles and a superior rate capability of 555.4 mA h g −1 at 2000 mA g −1 over 500 cycles. So far, MoS 2 /SnS 2 -RGO possesses the highest reversible capacity among the reported anode materials . Furthermore, a SIC composed of optimized MoS 2 /SnS 2 -RGO anode and a CC cathode reaches a high specific energy of 113.9 W h kg −1 at specific power of 561.25 W kg −1 . Similarly, a SIB consisted of the MoS 2 /SnS 2 -RGO anode and a Na 3 V 2 (PO 4 ) 3 /C cathode displays the reversible discharge capacity of 56 mA h g −1 at the high rates of 2 C.
研究领域:
材料科学
·
能源存储
·
电化学
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DOI
高影响因子
CARBON
·
2023
·
IF 10.9
Xianwei Li,Zhenqian Wu,Xudong Ma,Ling Xin,Xiao Yu,Yong Liu
Carbonaceous materials , such as hard carbon and porous carbon , have gained great attentions as the anode materials for Na-ion batteries (NIBs). However, their defects and disordered structure cause the low initial coulombic efficiency (ICE), high-potential slope region and small charge capacity below 0.5 V. Herein, a structurally stable MOF contained 1,3,5-triazine-2,4,6-triamine moieties, belonging to the tetragonal space group I 4/m, is synthesized. On this basis, MOF-derived crystalline carbon with graphite-like crystal, instead of amorphous porous carbon, can be obtained due to slow pyrolysis of MOF framework along with timely and sufficient reassembly of the pyrolyzed carbon atoms into graphite-like crystal under graphite-induced condition. The graphite-like crystal has a geometrically similar unit cell to graphite crystal but with a magnification ratio of 1.25, yielding proportionally expanded d-spacing of (002) plane (4.2 Å), which enables the reversible Na + intercalation/de-intercalation. When applied in NIBs, it exhibits a very high ICE of 96.0% and reversible charge capacity of 356.2 mAh g −1 , reaching the advanced level of graphite applied in LIBs . More importantly, its charge capacity below 0.5 V can account for 90% of the total charge capacity, which is also the key parameter to effectively increase the energy density of full batteries.
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高影响因子
RSC Advances
·
2023
·Vol. 13
·期 10
·7030-7036
·
IF 3.9
Xiunan Yao,Ninglian Wang,Xingwang Zheng,Quanlian Li,Ewerton Santos,Linda Maharjan,Junjie Wang,Zhihui Guo,Jiahua Guo,Huan Zhang,Kui Zheng,Jingquan Wu,Yao Li
The sensitive determination of levoglucosan in aqueous samples has great significance for the study of biomass burning. Although some sensitive high-performance liquid chromatography/mass spectrometry (HPLC/MS) detection methods have been developed for levoglucosan, there are still plenty of shortcomings, such as complicated sample pre-treatment procedures, large-amount sample requirements, and poor reproducibility. Herein, a new method for the determination of levoglucosan in the aqueous sample was developed using ultra-performance liquid chromatography with triple quadrupole mass spectrometry (UPLC-MS/MS). In this method, we firstly found that compared with H+, Na+ could effectively enhance the ionization efficiency of levoglucosan, even though the content of H+ is higher in the environment. Moreover, the precursor ion m/z 185.1 [M + Na]+ could be used as a quantitative ion to sensitively detect levoglucosan in aqueous samples. Only 2 μL of un-pretreated sample is required for one injection in this method, and great linearity was obtained (R2 = 0.9992) using the external standard method when the concentration of levoglucosan was 0.5–50 ng mL−1. The limit of detection (LOD) and quantification (LOQ) were 0.1 ng mL−1 (0.2 pg absolute mass injected) and 0.3 ng mL−1, respectively. Acceptable repeatability, reproducibility, and recovery were achieved. This method has the advantages of high sensitivity, good stability, good reproducibility, and simple operation, which could be widely used for the detection of different concentrations of levoglucosan in various water samples, especially for the detection of samples with low content such as ice core or snow samples.
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xin Hou,Tianyu Li,Yanling Qiu,Mingqin Jiang,Qiong Zheng,Xianfeng Li
Electrolyte plays an important role in conducting sodium ions and carrying out chemical/electrochemical reactions. However, the impact mechanism of microscopic solvation structure remains vague but is significant for the electrolyte design. Here we reveal that the inner relationship between solvation structure and electrochemical reaction is manifested intuitively by manipulating the anions in the solvated shell, which determines Na storage kinetics and SEI evolution process. The result elucidates the weak coulomb interaction between PF 6 − and Na + could promote Na + transport number in bulk liquid and Na storage kinetics. And it could induce PF 6 − to reduce preferentially and facilitate additive to enter solvation structure, thereby forming a thin&compact&protective SEI with layered morphology. The excellent SEI would protect anode effectively, inhibiting decomposition of solvents and improving battery performances. As expected, 5 Ah Na 3 V 2 (PO 4 ) 3 -hard carbon pouch-type batteries with well-matched PF 6 − -based electrolyte display a high specific energy of 129 Wh kg −1 , a superior rate capability with capacity retention of 90 % at 5 C and cycling stability with retention of 86.82 % at 1 C after 700 cycles.
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高影响因子
ANALYTICA CHIMICA ACTA
·
2022
·
IF 6.911
Yuan Su,Xuetong Li,Longjiao Zhu,Huashuo Chu,Yangzi Zhang,Jingjing Tian,Shuxia Lyu,Wentao Xu
To develop an on-site, thermostatic and rapid sensor for the detection of Vibrio parahaemolyticus (V. parahaemolyticus) , A single cross-priming fluorescence (SCPF) sensor was designed using a 3D nano-nucleic acid hybrid material that termed mesoporous silica nanoparticle/nucleic acid-doped nanoflower (MSN/NA-doped nanoflower). In addition, a portable polymerase chain reaction (PCR) tube fluorescence reader was built. Further analysis of the MSN/NA-doped nanoflower morphology and the enhancement mechanism indicated that the MSNs aggregated into larger nanoclusters by adsorbing single cross-priming amplification (sCPA) components, forming MSNs/NAs-doped nanoflowers, and increasing the local concentrations to enhance sCPA efficiency. Cyclic amplification relied mainly on the self-folding hairpin-like structure of the amplified product that continuously formed, opened, re-formed, and opened again. The target DNA was detected with a detection limit of 2.4 copies/μL.
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DOI
PubMed
高影响因子
Chemical Science
·
2023
·Vol. 14
·期 44
·12570-12581
·
IF 8.4
Mingli Xu,Fengxue Zhang,Yanhui Zhang,Chen Wu,Xue Zhou,Xinping Ai,Jiangfeng Qian
Exploring a sodium-enriched cathode (i.e. Na4V2(PO4)3, which differs from its traditional stoichiometric counterpart Na3V2(PO4)3 that can provide extra endogenous sodium reserves to mitigate the irreversible capacity loss of the anode material (i.e. hard carbon), is an intriguing presodiation method for the development of high energy sodium-ion batteries. To meet this challenge, herein, we first propose a redox-potential-matched chemical sodiation approach, utilizing phenazine-sodium (PNZ-Na) as the optimal reagent to sodiate the Na3V2(PO4)3 precursor into Na-enriched Na4V2(PO4)3. The spontaneous sodiation reaction enables a fast reduction of one-half V ions from V3+ to V2+, followed by the insertion of one Na+ ion into the NASICON framework, which only takes 90 s to obtain the phase-pure Na4V2(PO4)3 product. When paired with a hard carbon anode, the resulting Na4VP‖HC full cell exhibits a high energy density of 251 W h kg−1, which is 58% higher than that of 159 W h kg−1 for the Na3VP‖HC control cell. Our chemical sodiation methodology provides an innovative approach for designing sodium-rich cathode materials and could serve as an impetus to the development of advanced sodium-ion batteries.
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PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2019
·
IF 2.298
Zhongshu Li,Yuli Xue,Xiaoling Tan,Wenqing Li,Shaonan Xu,Ziyan Wang,Jian Wang,Lina Li,Shiding Miao
It is of great importance to separate potassium salts from carbonate-based lakes, especially the low-[K+] but high-[Na+] brine which has been discovered around the world. Here the phase diagram of the quaternary system Na+, K+//Cl–, CO32––H2O was experimentally studied at 298.15 K via the method of isothermal evaporation, and the results corrected the previous diagram reported by Blasdale (J. Am. Chem. Soc.1923, 45, 2935–2946). The type of salts appeared and their solubility during the evaporation, and the density vs composition diagram and the pH values were plotted based on the experimental data. It was found that there were six invariant points, seven univariant curves, and five crystallization fields in the equilibrium phase diagram. To extract single-salt of potassium, certain areas in the Na+, K+//Cl–, CO32––H2O diagram were chosen to be acidified by the compressed CO2, and potassium in the form of KHCO3 was precipitated from the mother solution. The compressed CO2 was able to avoid formation of NaKCO3·6H2O during evaporation of the original system Na+, K+//Cl–, CO32––H2O. Based on experiment data, the region area for potassium salt extraction was determined, and this area was suitable for extracting K+ salts from brines with a [Na+/K+] ratio even lower than 0.44. This strategy opened a new way to recovery of potassium with a maximum yield of 59.88% from the carbonate-chloride-based brine.
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Chunqing Cai,Fan Yang,Zhigang Zhao,Qiuxia Liao,Ruixi Bai,Wanghuan Guo,Peng Chen,Yang Zhang,Hao Zhang
This paper first reports on the high-selective separation and recovery of Li(I) from Na(I) and K(I) using the polymer inclusion membrane (PIM) system containing both thenoyltrifluoroacetone (TTA) and trioctylphosphine oxide (TOPO) as the carrier molecules, and cellulose triacetate (CTA) as the base polymer. To characterize the PIM, we used Fourier Transform infrared (FT-IR) spectroscopy, scanning election microscopy (SEM) and thermogravimetric analysis (TGA). The optimized results of this work showed that initial flux ( J 0 ) of Li(I) that was as high as 1.04 × 10 −2 mol m −2 h −1 , corresponding to permeability ( P ) of 3.62 × 10 −3 m h −1 , were recorded using the PIM composed of 50 wt% CTA and 26.74 wt% TTA + 23.26 wt% TOPO from a feed phase containing Li(I), Na(I) and K(I) in an alkaline chloride solution into an acceptor phase containing 0.1 M HCl. Li(I) was transported successfully to the acceptor phase but Na(I) and K(I) barely passed in the first 20 h. The separation factor ( S F ) of Li(I) over the Na(I) and K(I) respectively ( S F L i ( I ) / N a ( I ) ≒ 54.25, S F L i ( I ) / k ( I ) ≒ 50.60) demonstrated that Li(I) can be high-selectively separated. It is expected that this membrane can be applied for selective recovery of Li(I) from salt lakes or sea water that contains significant concentrations of Na(I) and K(I).
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高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2016
·
IF 1.835
Dawei Li,Guangqian Li,Pingfeng Bian,Zhe Shen,Mengfan Fu,Wenjun Fang,Weidong Yan
Epigallocatechin gallate (EGCG) is the most abundant and active components in tea. In this text, the density and viscosity of ternary aqueous solution of EGCG containing LiCl/NaCl/KCl were determined at temperatures ranging from 288.15 to 308.15 K at atmospheric pressure. The density data was used to compute the apparent molar volumes (Vφ), limiting partial molar volumes (Vφ0), and transfer partial molar volumes (ΔtrsVφ0). The viscosity B-Coefficients were calculated from the measured viscosity data using the extended Jones–Dole equation. The values of density and viscosity increased continuously with the increasing of molality of EGCG and decreased with the temperature increasing. The positive values including (Vφ, Vφ0, ΔtrsVφ0, viscosity B-Coefficients, the free energies of activation for solvent Δμ10≠, and for solute Δμ20≠) and Helper’s constant (∂2Vφ0/∂T2)p close to zero indicated the presence of strong solute–solvent interactions and the structure–making effect of EGCG in the investigated solutions. The apparent molar isobaric expansions (Eφ0) decreasing with temperature suggested that the solute–solvent interactions became weaker as temperature increased. These significant parameters could provide necessary data about molecular interactions occurring in simulated body fluids.
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高影响因子
危险品化学品经营许可证（带存储）