CHEMICAL COMMUNICATIONS
·
2015
·Vol. 51
·期 15
·3227-3230
·
IF 6.834
Maowen Xu,Jun-Ke Hou,Yu-Bin Niu,Guan-Nan Li,Yu-Tao Li,Chang Ming Li
Na2.65Ti3.35Fe0.65O9 rods were prepared by a simple solid-state route and coated with carbon to enhance their electronic conductivity. For the first time, Na2.65Ti3.35Fe0.65O9 was explored as an anode material for Na-ion batteries to deliver a discharge capacity of 137.5 mA h g−1 at a current rate of 40 mA g−1. The charge/discharge capacity of a carbon-coated sample increased by 46.3% to achieve 201.1 mA h g−1.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
IONICS
·
2019
·Vol. 26
·期 2
·627-637
·
IF 2.289
Zhai Huanhuan,Shuai Yi,Wang Yu,Chen Kanghua
As a negative electrode material, the main drawbacks of Li 4 Ti 5 O 12 (LTO) are its low electric conductivity and poor Li-ion diffusion coefficient. Fortunately, elements modification to address these problems is an effective method. Herein, we firstly report Ni and F co-modified LTO material which is synthesized via a solid-state reaction. Powder X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy were conducted to investigate the structure and morphology. Afterwards, we surprisingly find that Ni and F co-modification can reduce the overall charge transfer resistance of LTO for part of Ti 4+ converts into Ti 3+ and Ni 2+ ions supply the charge carriers. When test in battery, a superior discharge capacity of 236.1 mAh g −1 at 0.036 A g −1 is obtained, much higher than that of pristine LTO (196.9 mAh g −1 ). Furthermore, it still retains a discharge capacity of 174.6 mAh g −1 after 200 cycles at 0.18 A g −1 and exhibits an excellent rate performance.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Jinxing Yu,Lei Zhang,Jun Qian,Zhirong Zhu,Shuang Ni,Gang Liu,Xiaoxiang Xu
Starting from two wide band gap semiconductors AgTaO 3 and SrTiO 3 , we managed to reduce the band gap by forming their solid solutions, i.e. (AgTaO 3 ) 1-x (SrTiO 3 ) x (0.0 ≤ x ≤ 1.0). These solid solutions all adopt cubic perovskite structure similar to SrTiO 3 and high temperature phase of AgTaO 3 , suggesting that SrTiO 3 is helpful to stabilize AgTaO 3 in its high temperature cubic phase. Substantial improvements over photocatalytic hydrogen production were realized in these solid solutions which clearly outperform their parent compounds AgTaO 3 and SrTiO 3 . In-situ exolution of silver nanoparticles at the surface of solid solutions (x = 0.2) substantially strengthen the visible light absorption due to localized surface plasmons of these silver nanoparticles . This contributes to further improvements on both photocatalytic hydrogen and oxygen production under visible light illumination (λ ≥ 400 nm). Apparent quantum efficiency as high as ˜ 2.02% and ˜ 0.11% was achieved at solid solutions (x = 0.2) decorated with silver nanoparticles for full range (λ ≥ 250 nm) and visible light (λ ≥ 400 nm) illumination respectively. Photoelectrochemical analysis suggests that solid solutions own a better charge separation conditions than their parent compounds. Furthermore, the band edge positions of solid solutions (x = 0.2) lie approximately in the middle between AgTaO 3 and SrTiO 3 , being ideal for solar water splitting reactions.
研究领域:
材料科学
·
光催化
·
能源化学
·
半导体物理
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
Haoxiang Yu,Minghe Luo,Hua Lan,Lei Yan,Shangshu Qian,Wuquan Ye,Miao Shui,Nengbing Long,Jie Shu
The preparation and characterization of Pb 1- x Ba x Li 2 Ti 6 O 14 ( x = 0, 1/4, 1/2, 3/4, 1) as anode materials for lithium ion batteries are investigated in this research. The structure, morphology and electrochemical properties are compared with each other by changing the Pb/Ba atomic ratio in Pb 1- x Ba x Li 2 Ti 6 O 14 . It can be observed that each sample shows the same orthorhombic structure with Cmca space group. Moreover, it can also be found that the working potential, conductivity, cycling and rate performances of as-received samples gradually change along with the evolution of x in Pb 1- x Ba x Li 2 Ti 6 O 14 ( x = 0, 1/4, 1/2, 3/4, 1). Electrochemical evaluation shows that the operating potential of the as-received sample gradually decreases with increasing x value in Pb 1- x Ba x Li 2 Ti 6 O 14 and its initial charge capacity increases reversely. Moreover, different Pb/Ba atomic ratio also brings different cycling stability for Pb 1- x Ba x Li 2 Ti 6 O 14 . Especially for Pb 3/4 Ba 1/4 Li 2 Ti 6 O 14 , it presents better electrochemical properties than other samples. After 120 cycles, the reversible capacity of Pb 3/4 Ba 1/4 Li 2 Ti 6 O 14 is maintained at 129.7 mAh g −1 with capacity retention of 88.3%. In addition, its electrochemical reversibility is also demonstrated by in-situ X-ray investigation.
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
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Lingwei Lu,Meilin Lv,Gang Liu,Xiaoxiang Xu
Constituting solid solutions has been an appealing means to gain control over various physicochemical properties. In this work, we synthesized a series of SrTiO 3 -BiFeO 3 solid solutions and systematically explored their structural, optical and photocatalytic properties. Our results show that all solid solutions crystallize in a primitive cubic structure and their band gap values can be easily tuned by adjusting molar ratios between SrTiO 3 and BiFeO 3 . Photocatalytic hydrogen production under both full range and visible light irradiation is greatly improved after forming solid solutions. The highest hydrogen production rate obtained is ∼180 μmol/h under full range irradiation (λ ≥ 250 nm) and ∼4.2 μmol/h under visible light irradiation (λ ≥ 400 nm), corresponding to apparent quantum efficiency ∼2.28% and ∼0.10%, respectively. The activity is found to be strongly influenced by surface area and light absorption. Theoretical calculation suggests that Fe contributes to the formation of spin-polarized bands in the middle of original band gap and is responsible for the band gap reduction and visible light photocatalytic activity .
研究领域:
材料化学
·
光催化
·
能源材料
·
无机固体化学
·
半导体物理
·
太阳能转化
·
表面科学
✓ 已验证
DOI
高影响因子
Green Energy & Environment
·
2020
·Vol. 7
·期 1
·53-65
·
IF 6.395
Hong-Li Ding,Hai-Tao Yu,Xiao-dong Wang,Chen-Feng Guo,Bing Zheng,Ying Xie,Ting-Feng Yi
SrLi 2 Ti 6 O 14 (SLTO) coated with different amount of ZrO 2 was successfully prepared. The as-obtained composites are stacked by a series of particles with a pure phase structure and a good crystallinity. Furthermore, ZrO 2 coating not only enhances the structural stability of the materials but also facilitates the diffusion of lithium through the SEI film. As a result, the redox polarization was reduced, and the reversibility of the electrochemical reaction was enhanced. Particularly, SLTO-ZrO 2 -2 sample delivers a high initial lithiation capacity of 283.6 mA h g −1 , and the values maintain at 251.7, 228.0, 207.4, 175.3, and 147.7 mA h g −1 at the current densities of 0.13, 0.26, 0.54, 1.31, and 2.62 A g −1 , respectively. Our experiment also confirmed that SLTO materials coated with ZrO 2 are suitable for high power density applications, and the lithiation specific energy efficiency of SLTO-ZrO 2 -2 is 200% as high as that of pure SLTO at a power density of 1257 W kg −1 .
研究领域:
材料科学
·
电化学
·
能源存储
·
无机非金属材料
·
固态离子学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2014
·
IF 5.211
Kaiqiang Wu,Jie Shu,Xiaoting Lin,Lianyi Shao,Peng Li,Miao Shui,Mengmeng Lao,Nengbing Long,Dongjie Wang
A series of Na x Li 4−x Ti 6 O 14 (0 ≤ x ≤ 4) are prepared by solid-state method and their structures, morphologies and electrochemical properties are compared by changing the Na/Li atomic ratio. It can be found that two single-phase samples of Na 2 Li 2 Ti 6 O 14 and Na 4 Ti 6 O 14 and three multi-phase samples of Li 4 Ti 6 O 14 (Li 4 Ti 5 O 12 /TiO 2 ), NaLi 3 Ti 6 O 14 (Na 2 Li 2 Ti 6 O 14 /Li 4 Ti 5 O 12 /TiO 2 ) and Na 3 LiTi 6 O 14 (Na 2 Li 2 Ti 6 O 14 /Na 2 Ti 3 O 7 ) can be formed by using a stoichiometric ratio of starting materials based on the formula of Na x Li 4−x Ti 6 O 14 . Besides, different Na/Li atomic ratios in Na x Li 4−x Ti 6 O 14 also induce the morphology evolution shifting from round-shape to polyhedron-shape, and then to square-shape with the increase of Na content. Electrochemical tests show that Li 4 Ti 6 O 14 delivers the highest charge capacities of 116 mAh g −1 at 100 mA g −1 , 91.5 mAh g −1 at 200 mA g −1 , 77.5 mAh g −1 at 300 mA g −1 and 66.9 mAh g −1 at 400 mA g −1 among five samples. For comparison, Na 4 Ti 6 O 14 only reveals the reversible capacities of 38.6 mAh g −1 at 100 mA g −1 , 30.2 mAh g −1 at 200 mA g −1 , 24.8 mAh g −1 at 300 mA g −1 and 20.9 mAh g −1 at 400 mA g −1 . It suggests that Li 4 Ti 6 O 14 is the most potential lithium storage material among all the Na x Li 4−x Ti 6 O 14 samples.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
功能材料
✓ 已验证
DOI
高影响因子
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
RSC Advances
·
2016
·Vol. 6
·期 72
·67827-67832
·
IF 3.289
W. X. Chen,J. S. Yu,W. Hu,Z. L. Chen,H. Memon,G. L. Chen
A core/shell heterostructured nanonanocomposite catalyst based on NiO nanoflakes and titanate nanowires (TNWs) was fabricated. The experimental results showed that the precursor concentration and the reaction time for NiO deposition played significant roles in determining the resulting heterostructure, and an optimal precursor's concentration would result in a well-defined core/shell heterostructure. The XRD analysis demonstrated the existence of the (1 1 1), (2 0 0) and (3 1 1) lattice planes of the NiO nanoflakes. Nearly 100% of the MB pollutant (10 mg L−1) was photodegradaded by the TNWs/NiO catalyst within 50 minutes under UV light irradiation.
研究领域:
材料化学
·
环境催化
·
纳米材料科学
·
光催化降解
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 11
·14274-14285
·
IF 2.478
Gao Qianqian,Dai Yuqiang,Wei Xile,Zhou Changping,Gong Wenfeng,Song Haixiang,Guo Zhanhu,Li Chengbo
The Aurivillius compound Pb x Bi 6− x Fe 0.5 Co 0.5 Ti 4 O 18 thin films were prepared via chemical solution deposition method and the influence of Pb 2+ ions doping on the structure, ferroelectric and leakage properties were studied. With the increasing concentration of Pb 2+ ions, the lattice distortion is increased and the growth of the films along ab plane is promoted. The calculation results show that the internal stress of the films increases with the increase of Pb 2+ concentration. For the samples with low Pb 2+ doping concentration ( x < 0.6), the leakage current densities are also decreased, which can be attributed to the decrease in oxygen vacancy concentration. Due to the enhanced lattice distortion and decreased leakage current densities, the ferroelectric properties are improved. The film with x = 0.2 has a high saturation polarization of 42.3 µC/cm 2 . According to the fitting results, the leakage conduction mechanism is attributed to the combined effect of space-charge-limited conduction mechanism and ionic conduction mechanisms.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
铁电学
·
薄膜制备
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·Vol. 44
·期 17
·21000-21003
·
IF 3.057
Jie Zhang,Zhenxing Yue,Yu Luo,Longtu Li
A cofired trilayer ceramic architecture showing as MgTiO 3 /TiO 2 /MgTiO 3 was designed to realize temperature-stable and ultrahigh- Q microwave dielectrics in the typical MgTiO 3 -TiO 2 system. The effects of TiO 2 content on the microwave dielectric properties of cofired trilayer ceramics were studied. Through the design of cofired trilayer architecture, the chemical reactions between MgTiO 3 and TiO 2 were limited within a narrow region of MgTiO 3 /TiO 2 interfaces (~ 15 µm in width), which could be beneficial for optimizing the microwave dielectric properties. Excellent characteristics of ε r ~ 18.38, Q×f value ~ 169,900 GHz and τ f ~ − 1 ppm/°C were gained for the MgTiO 3 /TiO 2 /MgTiO 3 ceramic architectures stacked with 1.63 vol% TiO 2 . The current work could serve as new strategies to develop high-performance dielectric resonators and multilayers for 5G wireless communication applications.
研究领域:
材料科学
·
无机非金属材料
·
电子陶瓷
·
微波介质材料
·
功能陶瓷
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2019
·Vol. 125
·期 3
·158
·
IF 1.784
Gao Dong-Sheng,Gao Xiang-Dong,Wu Yong-Qing,Zhang Tong-Tong,Yang Jing-Nan,Li Xiao-Min
Co doped BaSnO 3 films [BaSn 1 − x Co x O 3 (0 ≤ x ≤ 0.50), i.e., BSCO] have been grown on MgO single-crystal substrates via pulsed laser deposition. Effects of the Co-doping level on the crystallinity, the microstructure, and optical properties of the BSCO films are investigated. All the BSCO films are of high crystallinity and grown epitaxially on MgO substrates. The lattice parameter of the (200) plane drops linearly with the increase of the ‘ x ’ value. The Co doping is found to increase the film roughness and the grain size, and a RMS roughness of 8.33 nm and grain size up to 100 nm are observed in the film with x = 0.50. The low Co-doping level ( x = 0.05, 0.1) has slight anti-reflection effects on the incident visible light, and the Co-doping level higher than 0.2 reduces the optical transmittance significantly. The optical bandgap shows a first-rising then falling trend with the increase of the Co content, and the lowest bandgap of 1.94 eV is realized in the BSCO film with x = 0.50.
研究领域:
材料科学
·
凝聚态物理
·
薄膜制备
·
光学材料
·
功能氧化物
✓ 已验证
DOI
高影响因子