SOLID STATE IONICS
·
2018
·
IF 2.751
Xue Bai,Wen Li,Aijia Wei,Qian Chang,Lihui Zhang,Zhenfa Liu
Spinel Li 4 Ti 5 O 12 doped with F was synthesized via the solid-state reaction of anatase TiO 2 , Li 2 CO 3 , and NH 4 F. The structural characterization and electrochemical performance evaluation of the prepared materials were carried out utilizing X-ray diffraction, scanning electron microscopy, galvanostatic charge-discharge, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) tests. The lattice parameters of all samples were calculated using an internal standard and Rietveld refinement method. The results indicate that the F was successfully doped into the lattice structure of Li 4 Ti 5 O 12 , and this process did not influence the crystal structure and superficial morphology. Moreover, the best-performing material, Li 4 Ti 5 O 11.9 F 0.1 delivers superior rate capacities of 165, 162.1, 160.0, 142.3, 125.1, and 99.2 mAh g −1 , at 0.2 C, 0.5 C, 1 C, 3 C, 5 C, and 10 C, respectively, which is higher than those of Li 4 Ti 5 O 12 (150.0, 135.0, 123.5, 93.7, 76.4, and 56.8 mAh g −1 at the same C-rates), and the cycling retention is 82.7% after 150 cycles at 5 C. Meanwhile, the charge-transfer resistance (R ct ) of Li 4 Ti 5 O 11.9 F 0.1 (56.4 Ω) is lower than that of pure Li 4 Ti 5 O 12 (80.6 Ω), and the lithium-ion diffusion coefficients (D Li + ) of Li 4 Ti 5 O 11.9 F 0.1 (2.505 × 10 −10 cm 2 s −1 ) is higher than that of pure Li 4 Ti 5 O 12 (1.694 × 10 −10 cm 2 s −1 ).
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·Vol. 45
·期 8
·10633-10639
·
IF 3.45
Guorong Hu,Zhichen Xue,Zhongyuan Luo,Zhongdong Peng,Yanbing Cao,Weigang Wang,Yuexi Zeng,Yong Huang,Yong Tao,Tianfan Li,Zhiyong Zhang,Ke Du
The Li-rich cathode material for long cycle performance and long-term storage performance is a challenge for next-generation lithium-ion batteries due to the rapid capacity degradation over cycling and the formation of residual lithium on the surface during long-term storage. Herein, an elevated performance of Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 materials via CeO 2 inlay is reported, which was prepared from Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 by sol-gel inlay with CeO 2 . It was proved by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy that cerium oxide cladding not only covered the surface of the material but also diffused into the interior of the material change crystal structure. Cerium oxide on the cladding not only reduces the material's contact with water and carbon dioxide in the air, but also prevents the material from being corroded by electrolyte during electrochemical test. The position of the transition metal atom is replaced Ce atoms, which increases the unit cell volume and the stability of the Li-rich material during the cycling. The results show that the storage property and the electrochemical cycling property of the material have been improved obviously. The CeO 2 inlaid lithium rich material discharged 204.6 mAh/g for the first time at the current of 1C, and 164.4 mAh/g after 150 charge and discharge cycles with corresponding capacity retention rate of 80.35%, compared with the retention rate of 57.26% for pristine Li-rich material capacity. After being stored in humid air for 40 days, the CeO 2 inlaid lithium-rich material showed better electrochemical performance than the pristine one. It is powerfully demonstrated that the CeO 2 inlay strategy here holds huge promise for surface modification of electrode materials for lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
锂离子电池
·
能源存储
·
无机非金属材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Jianwei Bai,Xiaofei Ma,Cen Gong,Yiming Chen,Huijun Yan,Kewei Wang,Jun Wang
Traditional adsorption resin prepared by a low efficiency method has a low porosity and surface area , which limits the adsorption performance of the resin. Therefore, a novel porous resin was developed by structural design of the resins through post- modification with HPA and a post-crosslinked method. The novel porous post-modification resin was successfully prepared by the multistep method. Meanwhile, the high surface area and abundant micropores in HCR-AO can improve the adsorption rate by accelerating the diffusion of uranium in the external diffusion stage. The removal capacity of HCR-AO increased 366% for HCR and 120% for PSD-AO at the same initial concentration. HCR-AO takes less time to reach equilibrium than PSD-AO and HCR. Excitingly, the adsorption amount of the material dropped only slightly even after 8 cycles. The short equilibrium time and outstanding removal efficiency makes it a novel candidate for further extraction of U (VI) from seawater .
研究领域:
环境化学
·
核化学
·
材料科学
·
吸附分离
·
海洋资源提取
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Xiaozhong Zhou,Zhaoyi Qi,Yuyuan Jiang,Pengfei Yan,Juanxia Ding,Haiyan Wang,Hongkai Lu,Dongxu Liu,Kaifa Dong,Yougen Tang,Dongfei Sun,Ziqiang Lei
SiO x is regarded as a promising anode material for the next-generation lithium-ion batteries with high energy density. However, the reduplicative volume changes during cycling cause the pulverizations of Si, leading to decreased utilization of active Si component and poor cycling performance. Herein, a facile and scalable Fe-Cr decorating strategy is reported to boost the lithium storage of SiO x anode. Our comprehensive characterizations indicate that there are strong interactions between Fe-Cr and SiO x during a facile ball milling process. After cycling, Fe-Cr nanoparticles are dispersed in the in-situ formed lithium silicates and Li 2 O matrix, which can maintain superior conductivity of lithium ion and electron for the active components through point-to-point connections. This unique structure boosts the electrochemical de-alloying process of the low-valent Li x Si (0 ≤ x ≤ 2), and increases effective utilization of the active Si component during cycling, resulting in improvement of reversible capacity and cycling stability. This bm SiO x -FeCr electrode can deliver high reversible specific capacity (1370 m Ah g −1 at 200 mA g −1 ), good rate capability (653.8 m Ah g −1 at 2000 mA g −1 ), and superior cycling stability. This work provides a promising route for improving the utilization of active Si component and the structural stability of SiO x -based anodes.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
电池技术
·
固态物理
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 16
·13384-13391
·
IF 3.289
Bin Lu,Renzong Hu,Jiangwen Liu,Jun Liu,Hui Wang,Min Zhu
To improve the coulombic efficiency (CE) and cycle life of SnO2 anode in lithium ion batteries, SnO2–Cu–graphite composites with dual scale embedding structure are synthesized by ball milling. The SnO2–Cu composite, in which SnO2 nanoparticles with grain size less than 10 nm are uniformly dispersed in inactive nanocrystalline Cu matrix, is firstly obtained by milling the mixture of SnO2 and Cu nanopowders (molar ratio 1 : 2), and then further milling with graphite (C) to obtain SnO2–Cu–C composite with microsized graphite sheets as matrix of SnO2–Cu composite. The 50 h-milled SnO2–Cu composite exhibits higher initial CE (76.0 ± 1.5%) and subsequent CE than 50 h-milled SnO2. Furthermore, the SnO2–Cu–C composite anode is capable of retaining a maximum charge capacity of 450.8 mA h g−1 at 100 mA g−1 after 80 cycles with a capacity retention ratio of 74.4%, displaying superior cyclic stability to as-milled SnO2, SnO2–Cu and SnO2–C composites. The improved CE and cycleability are attributed to the unique dual scale embedding structure that offers good conductivity of electron and lithium ion as well as the nanostructure stability of active materials. This unique composite structure might be extended to other high-capacity anode materials, to achieve high performance lithium ion batteries.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
锂离子电池
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2016
·
IF 2.437
Yan Fang,Xiaohong Jiang,Lihong Niu,Shujie Wang
Polypyrrole/aligned carbon nanotubes (PPy/ACNTs) core-shell nanotube arrays on metal foil have been fabricated through an electrochemical method. The as-prepared PPy/ACNTs electrode materials with novel nanostructure , which is very conducive to the transmission of electrons and ions, possess greatly improved electrochemical performance. The specific capacitances of PPy/ACNTs electrode materials can reach 505 F/g ( vs. the both mass of PPy and ACNTs) in three-electrode system. In two-electrode system, the specific capacitances of the PPy/ACNTs electrode materials can reach 456 F/g ( vs. the both mass of PPy and ACNTs). The PPy/ACNTs electrode materials also exhibit greatly improved rate capability and superior cycling performance.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2012
·Vol. 39
·期 5
·5379-5385
·
IF 1.751
Jingjing Zhou,Jiefeng Zhou,Yuanhao Tang,Yujing Bi,Chenyun Wang,Deyu Wang,Siqi Shi
Using NaF as the only Na precursor, fluorophosphate Na 2 FePO 4 F/C materials have been synthesized via the solid-state reaction. Na 2 FePO 4 F starts to form at 300 °C, becomes the sole crystalline form between 400 and 600 °C, and decomposes at 650 °C. Comparing with the theoretical capacity of 124 mAh g −1 , the sample prepared at 600 °C delivered a discharge capacity of 118 mAh g −1 . The outstanding electrochemical performance is believed to result from the good crystallization and high purity of the synthesized materials . The capacity retentions at 0.5 C and 2 C are 95.8% and 89.8%, respectively, of that at 0.05 C. Furthermore, a discharge capacity of 122 mAh g −1 is maintained under the cycling between 2.0 and 5.2 V vs. Li/Li + , indicating that the second Na + is not extracted from the Na 2 FePO 4 F lattice.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固体化学
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Juguo Dai,Lili Luo,Xiaohong Wang,Long Xia,Hongmei Xie,Chunying Yang,Ruipan Wang,Yiting Xu,Lizong Dai
Nowadays, energy conversion devices have gradually gained attention while vigorously developing clean energy. Carbon materials are promising candidates for supercapacitors , but two issues have plagued the researchers. 1) Does the cation radius in the neutral electrolyte significantly impact the electrochemical performance of carbon materials? 2) How to introduce heteroatoms while constructing hollow structures in carbon spheres. This work proposes a facile template free strategy that uses aniline and pyrrole as nitrogen sources to synthesize carbon sphere precursors. High-temperature carbonization combined with alkali treatment leads to the formation of N-doped hollow porous carbon spheres. Robust wall structure (thickness is about 60–80 nm) and ideal surface structure (the specific surface area is 1079.9 m 2 g −1 ) endow the carbon spheres with excellent electrochemical performance and outstanding cycle stability. The specific capacitance of the carbon spheres in Li 2 SO 4 and Na 2 SO 4 electrolytes under negative working potential (−0.8–0 V) are 378.4 and 367.6 F g −1 , respectively, at a current density of 1 A g −1 . After 5000 cycles, the capacitance retentions are 87.1% and 94.8% in Li 2 SO 4 and Na 2 SO 4 electrolytes. We inferred that the cation radius has a negligible effect on the specific capacitance of carbon materials, but has a more significant effect on the cycling stability and capacitance rate performance. It is hoped that this work can provide a reference for the subsequent construction of N-doped hollow carbon spheres and reasonable selection of electrolytes.
研究领域:
材料科学
·
电化学
·
纳米能源
·
功能材料
·
储能技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 80
·76905-76914
·
IF 3.289
Liujie Zhang,Ying Kuang,Jia Liu,Zhilan Liu,Shiwen Huang,Renxi Zhuo
In this paper, a receptor-mediated liposomal drug delivery system (DDS) was developed aiming to deliver cisplatin (cis-diaminedichloroplatinum(II); CDDP) targeting the liver. Acetyl glycyrrhetinic acid (AGA) was chosen as the hepatic targeting ligand and acetyl glycyrrhetinic acid-poly(ethylene glycol)-stearate (AGA-PEG-ST) was synthesized. Anionic 5-cholestene-3-beta-ol-3-hemisuccinate (CHO-HS) was also synthesized. The liposomal CDDPs were prepared by employing these functional moieties with phosphatidylcholine (PC) at various ratios. Meanwhile, methoxypolyethylene glycol-stearate (MPEG-ST) with an analogous structure but without AGA was also prepared as a control. The particle sizes of AGA modified liposomes ranged from 120 nm to 180 nm and the zeta potentials were located between −39.7 mV and −3.18 mV. The liposomes had encapsulation percentages of 51.5–61.7% and a loading capacity of 23.2–26.7% for CDDP. The transmission electron microscopy (TEM) observations showed that the liposomes had spherical morphologies with homogeneous distribution. In vitro cytotoxicity of CDDP-loaded liposomes against HepG2 human liver cancer cells and A549 human lung epithelial carcinoma cells were evaluated by MTT assays. The results demonstrated that the introduction of AGA could enhance the cytotoxicity of liposomal CDDP against HepG2 cells but showed less significant impact on A549 cells. CLSM observation and FCM measurement further confirmed that AGA modified liposomes had a stronger affinity to HepG2 cells than that of liposomes without AGA. The tissue distribution of calcein in mice indicated that AGA modified liposomes resulted in higher accumulation in the liver than that of liposomes without the AGA ligand. These results demonstrated the promise of AGA decorated anionic liposomes for hepatic targeted delivery of cisplatin.
研究领域:
药剂学
·
肿瘤学
·
纳米医学
·
药物递送系统
·
肝病学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yaoliang Huang,Yunru Zhang,Guizhi Yuan,Dingshan Ruan,Xinlong Zhang,Weijian Liu,Zhongshuai Zhang,Xiaoyuan Yu
Ni/Mn-based layered oxides have been widely studied for sodium ion battery cathode because of high capacity and simple preparation. However, its application has been restricted owing to unstable structure and poor cycling performance. Herein, the multi-element doped hexagonal sheet Ni/Mn-based layered oxide with ZrO 2 surface modification O3-NaNi 0.3 Mn 0.5-x Fe 0.1 Cu 0.1 Zr x O 2 @ZrO 2 (NFMCZ-x) cathode materials have been successfully synthesize by high temperature calcination method accompanied by ball milling activation. XRD refinement results show Zr 4+ substitution of Mn 3+ can increase interlayer distance of sodium layer. Benefiting from the synergetic effect of multi-element doping and ZrO 2 surface modification, the optimized NFMCZ-0.03 sample exhibits a higher discharge capacity of 178 mAh/g at 0.1C and good capacity retention (77 % after 50 cycles at 2C). Furthermore, NFMCZ-0.03 has an excellent air stability with a capacity retention rate of 86 % during 50 cycles at 1C after being exposed in the air for 20 days. The ex-situ XRD results of NMFC at different charge/discharge voltages show Zr 4+ doping can suppress O3 + P3′'–O3′-O3 + P3′' phase transition during charge/discharge process. These results confirm that synergistic effect of multi-doping combined with surface modification can improve electrochemical performance of layered oxides cathodes, which provides a research idea for development of Ni/Mn-based layered oxides cathodes for sodium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Aijia Wei,Wen Li,Qian Chang,Xue Bai,Rui He,Lihui Zhang,Zhenfa Liu,Yanji Wang
Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 cathode material was synthesized by a facile one-step solid-state process. The effect of Mg 2+ /F − co-doping on grain morphology, phase structure, and electrochemical properties was studied by a series of characterizations. Scanning-electron-microscopy images show that Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 (denoted LNMO-MF) particles grow larger than pure LiNi 0.5 Mn 1.5 O 4 particles. X-ray diffraction, Raman spectra , Fourier transformation infrared spectroscopy , X-ray photoelectron spectroscopy, and cyclic-voltammetry tests indicate that all samples mainly display a Fd -3m space group and more Mn 3+ ions in the LNMO-MF sample after Mg 2+ /F − co-doping, which is conducive to increasing the cationic disorder degree and enhancing the electronic conductivity of electrode material. Results show that the LNMO-MF cathode material delivers an excellent rate performance with discharge capacities of 142, 144, 140 136, 132, 124, 115, and 100 mAh g −1 at 0.2, 0.5, 1, 2, 3, 5, 7, and 10C (1C = 140 mAh g −1 ), respectively. Remarkably, LNMO-MF also shows cycling stability with a capacity retention of 86.2% at 5C after 400 cycles, which is much higher than that of pure LiNi 0.5 Mn 1.5 O 4 (67.7%). The improvement of LNMO-MF's electrochemical properties could be ascribed to the Mg 2+ /F − co-doping, delivering a more stable structure, better crystallinity , the highest Li + diffusion coefficient , and the lowest charge-transfer resistance.
研究领域:
材料科学
·
电化学
·
无机非金属材料
·
能源存储
·
锂离子电池
·
固态化学
·
功能材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2011
·Vol. 36
·期 13
·7374-7380
·
IF 4.057
Wei Wang,Qiang Zhao,Jinxiang Dong,Jinping Li
A novel silver oxides oxygen evolving catalyst (Ag-OEC) for hydrogen production by water splitting was formed in situ on an indium tin oxide anode, in a near-neutral potassium tetraborate (K 2 B 4 O 7 ) electrolyte. The catalyst exhibited high activity and low overpotential for O 2 evolution under mild conditions. The main functional composition of the catalyst was a redox couple of Ag 2 O/AgO. Catalytic activity during oxygen evolution was evaluated by cyclic voltammetry and Tafel plot. The effects of the concentration, temperature, and pH of K 2 B 4 O 7 solution on the catalyst, and the Faradaic efficiency of the oxygen evolving reaction were examined. The results show that the Ag-OEC exhibits excellent oxygen evolution properties, with an oxygen evolving overpotential of 318 mV at a current density of 1 mA/cm 2 .
研究领域:
电催化
·
能源化学
·
材料科学
·
物理化学
·
可持续能源
✓ 已验证
DOI
高影响因子