ELECTROCHIMICA ACTA
·
2017
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IF 4.798
Xiaobo Jia,Mo Yan,Ziyou Zhou,Xianglei Chen,Chao Yao,De Li,Daming Chen,Yong Chen
Layered Nd-doped LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) compounds were successfully synthesized via a coprecipitation-assisted solid-phase method in this work. The effects of Nd doping on the crystal structure, morphology, and electrochemical properties were characterized thoroughly using XRD, SEM, TEM, EDX, and electrochemical tests. Rietveld refinement of the X-ray diffraction data indicated that the Nd-doped samples had lower cation mixing than the raw NCM523. The SEM and EDX mapping characterization results demonstrated that Nd atoms were uniformly distributed in NCM523. At 1C and 10C, the Li(Ni 0.5 Co 0.2 Mn 0.3 ) 0.992 Nd 0.008 O 2 materials exhibited initial discharge capacities of 189.7 and 101.5 mAh g −1 , respectively, with capacity retentions of 83.3% and 88%, respectively, compared to those of NCM523 (68.1% and 52.5%, respectively) with a cutoff voltage of 4.8 V after 100 cycles. It was found that NCM523 doped with Nd 3+ ions can expand lithium ion diffusion channels in the layered structure and stabilize the structure of the material.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Energy & Fuels
·
2019
·Vol. 3
·期 11
·3234-3243
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IF 4.912
Shiyi Deng,Yunjiao Li,Qiongyu Dai,Jiamin Fu,Yongxiang Chen,Junchao Zheng,Tongxing Lei,Jia Guo,Jing Gao,Wei Li
The elevation of energy density is the constant pursuit of the lithium-ion battery industry. LiNiO2 has reacquired recognition because it exhibits high capacity without an increase in the cut-off voltages. To address the flaws of this kind of cathodes, herein, trace nano-TiO2-modified LiNiO2 was synthesized via a simple solid-state method. Via combined characterization, the Ti element was verified to be doped into the bulk lattice and located at the transition-metal sites; after Ti doping, the Ni2+ content was clearly increased due to charge balance, followed by an increase in the Li/Ni disorder. The doped Ti and the as-generated Ni pillar mutually facilitated the stabilization of the material structure and benefitted the Li+ de/insertion. Nanosized TiO2 participating in the calcination process could effectively homogenize the size of the primary particles, adjust the surface morphology and reduce the specific surface area of the material. This morphological regulation may be favorable for reducing the contact area of the cathode with the electrolyte and establishing a stable electrode/electrolyte interface, where some detrimental side-reactions take place. With respect to electrochemical properties, Ti doping could decrease the electrode polarization, lower the impedance and promote the Li+ transfer. As a result, the Ti-modified LiNiO2 cathodes, especially the 0.2% Ti-doped (Ti-2) material, presented enhanced electrochemical performances.
研究领域:
材料科学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Yanqiu Zhang,Fan Yang,Songhe Qin,Junhui Huang,Xuyou Yang,Wenguang Wang,Yangxue Li,Chunrui Wu,Lu Shao
Nanofiltration with precise separation ability demonstrates the increasing importance in water treatment and high-value substance recycling compared with traditional energy-intensive separation technologies. Nevertheless, nanofiltration membranes still suffer from the permeance-selectivity “trade-off” issue. Herein, we designed the de novo nanofiltration membrane with enhanced separation performance by adopting deprotonated tannic acid (TA) as intermediate layer to tune pyrrole polymerizaiton for forming the polypyrrole selective layer. TA were coated followed by in-situ polymerization of pyrrole and they assembled based on the strong electrostatic and hydrogen bonding interaction. The deprotonation of phenolic hydroxyl groups in TA effectively regulated the polymerization process of pyrrole to obtain the synthesized nanofiltration membrane with the average pore diameter of 0.45 nm. The optimized nanofiltration membrane exhibited a 3.7-fold increase in permeance and almost complete rejection for various dyes with different molecular weights and charges, which breaks the permance-selectivity “trade-off”. In addition, the synthesized membrane possessed the excellent structural stability even in polar organic solvent of tetrahydrofuran. Our new strategy for constructing high-performance nanofiltration membrane via intermediate-layer-tuned formation/polymerization of the selective layer can provide an alternative potential avenue to fabricate next-generation molecular separation membranes towards environmental remediation and resource recovery.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2022
·
IF 6.364
Xuening Liu,Congxuan Su,Ya Zhong,Xiaofei Zhu,Zhanwu Wu,Sheng Cui
Dimensions and thermal insulation properties of nanoporous ceramics are unstable at high temperatures due to structural disruptions. This work prepared high entropy (LaCeSmEuNd) 2 Zr 2 O 7 ceramic aerogel via non-alkoxide sol-gel, supercritical drying, and calcination . XRD and EDS analysis showed that the (LaCeSmEuNd) 2 Zr 2 O 7 ceramic existed as a single phase. SEM images demonstrated the successful synthesis of aerogel structure. After two hours of annealing at 1200 °C, the cylindrical sample pressed from (LaCeSmEuNd) 2 Zr 2 O 7 ceramic aerogel had a compressive strength of 58.75 MPa, and its diameter shrinkage was 0.56%, whereas the La 2 Zr 2 O 7 reached 13.68%. The thermal diffusivity of annealed (LaCeSmEuNd) 2 Zr 2 O 7 was as low as 0.119 mm 2 s −1 , and its thermal conductivity at room temperature was 0.073 W·m −1 K −1 , which was attributed to lattice disorder, stable porous structure, and abundance of grain boundaries caused by high entropy effects. Extending the high entropy effect to ceramic nano-insulation products is beneficial for enhancing their thermal stability.
研究领域:
材料科学
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热能工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
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2023
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IF 9.9
Yiyun Cao,Lvji Yan,Haiyin Gang,Bichao Wu,Dun Wei,Peng Chen,Tingzheng Zhang,Haiying Wang
Exploring and designing high performance pseudocapacitance electrode materials is of great significance in enhancing the desalination performance of capacitive deionization (CDI). Transition metal cobalt is considered a prospective electrode material for CDI because of its abundance and high theoretical capacity, which can produce a higher salt removal capacity than pure capacitive materials in the CDI process. However, due to the collapse and loss of the active electrode crystal matrix, the cobalt electrode exhibits poor electrochemical performance. In this work, we used a second metal element, Fe, introduced by ion exchange pyrolysis to regulate the leaching effect and optimize the ion matching for cobalt to protect the electrode structure . In addition, the interconnected external carbon layers form a robust matrix for enhanced electrical conductivity with ion transport. Thanks to the synergistic effect of the cobalt‑iron (Co 3 Fe 7 @C) electrode structure and surface engineering, the adsorption capacity reached 72.29 mg·g −1 , achieving 110 % capacity retention in 100 cycles of chlorine removal. As a result, the carbon-coated cobalt‑iron bimetallic electrode exhibits excellent dechlorination capabilities in capacity, cycle life and rate capability. This study provides a promising avenue for the design of stable electrode materials for capacitive deionization electrodes.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
Results in Engineering
·
2023
·
IF 5
Hu Wang,Qing-rong Zheng,Xuan Zhang,Mengbo Wu
Measures beneficial to enhancing the hydro-stability of the HKUST-1 and improving its adsorptive performance for methane are crucial to the further application. In this research, incorporation of graphene oxide (GO) and carbonization were employed to achieve these objectives. Incorporation of the HKUST-1 was solvothermally prepared by mixing the GO with different mass ratios, and carbonization of the HKUST-1 sample was conducted at different temperatures. Structural characterization, structural morphology observation and adsorption equilibrium measurement of methane were then performed on the samples. Analysis of adsorption equilibrium of methane on the composite was finally carried out within temperature-pressure range respectively about 303.15 K–323.15 K and 0–3.6 MPa. It shows that the sample incorporated by 5 wt% GO has the largest increment about 11.7% and 13.3% in specific surface area and specific micropore volume, and the carbonization conducted at a temperature higher than 300 °C had negative effect on the structure stability of the sample. Results also reveal that the mean relative error between the experimental data and those predicted by Toth equation is about 0.54%. It suggests that the temperature for carbonizing should be carefully selected to avoid the collapse of the structure, and the balance measures should be taken to safeguard the benefit from incorporating.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Shiqiang Zhong,Jingwei Liu,Yongcong Huang,Yulin Cao,Feng Wu,Xuhui Li,Dawei Luo,Zhouguang Lu,Hua Cheng
Spinel LiMn2O4 (LMO) is a promising fast-charging cathode material because its unique three-dimensional Li-ion diffusion channels offer favorable ionic diffusivity. However, LMO encounters rapid structural degradation at high current densities. To tackle this issue, we introduce K+ ions into the interstitial 16c sites to stabilize LMO, thereby achieving excellent fast-charging capability. The K-LMO retains 75% of its theoretical capacity at an ultrahigh current density of 1.48 A g–1 (10 C, corresponding to a charging time of 5 min). Comprehensive characterizations demonstrate that the incorporation of K+ into LMO expands the LiO4 space, strengthens the Mn–O bonds and suppresses the Jahn–Teller effect, leading to improved Li-ion mobility and enhanced stability of the diffusion channels. Additionally, the volume variation induced by cycling under a high charge state is efficiently suppressed through a solid-solution transition, thus preventing structural degradation against long-term cycling. Given this, this study presents an attractive candidate material for the cathode of fast-charging lithium-ion batteries.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2024
·
IF 15.8
Lina Ge,Yijun Song,Pengchao Niu,Bingyu Li,Li Zhou,Wenting Feng,Chunxiang Ma,Xuejin Li,Debin Kong,Zifeng Yan,Qingzhong Xue,Yongpeng Cui,Wei Xing
Prussian blue (PB) is one of the main cathode materials with industrial prospects for the sodium ion battery. The structural stability of PB materials is directly associated with the presence of crystal water within the open 3D framework. However, there remains a lack of consensus regarding whether all forms of crystal water have detrimental effects on the structural stability of the PB materials. Currently, it is widely accepted that interstitial water is the stability troublemaker, whereas the role of coordination water remains elusive. In this work, the dynamic evolution of PB structures is investigated during the crystal water (in all forms) removal process through a variety of online monitoring techniques. It can be inferred that the PB-130 °C retains trace coordination water (1.3%) and original structural integrity, whereas PB-180 °C eliminates almost all of crystal water (∼12.1%, including both interstitial and coordinated water), but inevitably suffers from structural collapse. This is mainly because the coordinated water within the PB material plays a crucial role in maintaining structural stability via forming the −N≡C–FeLS–C≡N– conjugate bridge. Consequently, PB-130 °C with trace coordination water delivers superior reversible capacity (113.6 mAh g–1), high rate capability (charge to >80% capacity in 3 min), and long cycling stability (only 0.012% fading per cycle), demonstrating its promising prospect in practical applications.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Rui Li,Xiaoquan Feng,Huixian Wang,Donglai Peng,Shaochong Cao,Jingtao Wang,Yatao Zhang,Yong Wang
Laminar assembles of graphene oxide (GO) are receiving tremendous attention for their interesting nanofluidic behaviors, but suffer from structural instability and frustrated mass transfer. Herein, we stabilize GO assembles by “complementary nanosheets”, and thus obtain highly robust and permeable membranes. Self-exfoliated nanosheets of ionic covalent organic frameworks (iCONs) are intercalated into GO nanosheets . GO and iCONs are physicochemically complementary as they carry opposite charges and hydrogen bonds acceptors and donors, respectively. Upon mixing, they form laminar assembles locked by electrostatic attraction and hydrogen bonds, suppressing swelling in water. Moreover, simulation and experimental results reveal that iCONs expands the interlayer distance and provides additional mass-transport paths. Consequently, the GO/iCONs membranes exhibit ultra-high water permeance up to 11-fold larger than that of pure GO membranes. This work provides a controllable route to stabilize GO assembles, and develops new membranes using complementary two-dimensional structures as building blocks.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Hongtao Wu,Gaole Yan,Xiangyue Liu,Gang Yang
Manganese-based lithium-ion sieves (LISs) exhibit remarkable potential for lithium extraction from salt lakes owing to their excellent adsorption properties and high selectivity. However, manganese dissolution severely limits the industrial application of manganese-based LISs. Herein, a series of molybdenum (Mo)-doped manganese-based LISs (LMMO-X%) with high adsorption capacity were synthesised using the sol-gel method. Results indicate that the introduction of Molybdenum atom enhances the Mn(IV) content in the material while promoting the growth of the (111) crystal plane of Li 4 Mn 5 O 12 and suppressing the growth rates of the (110) and (100) crystal planes. Compared to the undoped ion sieve, the lithium adsorption capacity of the Mo-doped material increased from 35.56 to 44.63 mg/g, while the manganese dissolution rate decreased from 3.79 % to 2.63 %, considerably improving the overall performance of the LIS adsorbent. X-ray diffraction and X-ray photoelectron spectroscopy confirmed that Mo was successfully doped into the material, increasing the Mn(IV) content from 35.3 % to 56.5 %, enhancing the structural stability of the material and alleviating the Jahn–Teller distortion during the acid elution process. In addition, the adsorption process follows a pseudo-second-order kinetic model and the Langmuir isotherm adsorption model. In competitive salt solutions, LMMO demonstrates excellent selectivity for Li + and retains 80.73 % of its adsorption capacity after 10 cycles. This study provides a novel strategy for enhancing the structural stability of doping-modified materials.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Results in Physics
·
2024
·
IF 4.4
Bingguo Liu,Tong Wang,Shunzi Li,Jian Wang,Baofu Hu,Jian Xu,Baoli Du
Nano porous silicon (PS) is a strong candidate for thermoelectric application, but it shows low structural stability and is prone to collapse. To enhance the structural stability of PS and offer a new way to improve its electrical conductivity, PS was prepared by electrochemical etching and Bi nanowires were fabricated in the pores of PS by electrodeposition. In addition, for studying the effect of structures on the properties of Bi-filled PS composites, aperiodic single-layer (SL) structure, and periodic rugate (Rgt) structure and Bragg structure PS samples were prepared by changing the etching current waveform and etching time. The results show that the initial Bi deposition position and filling fraction of Bi nanowires in PS templates can be precisely controlled. Since Bi nanowires have significantly different continuity in Rgt and Bragg structures compared with SL structures, we proposed two growth mechanisms of Bi nanowires, including the axis-growth mechanism and transverse-axis-growth mechanism, with the supports of the experimental results of XRD, SEM, and EDS. The room temperature thermal conductivities of pristine and Bi-filled PS layers are in the ranges of 4.5 ∼ 5.0 and 4.2 ∼ 6.0 W･m −1 K −1 , respectively, about 1/10 of the original unetched silicon wafer. No apparent increase of thermal conductivity was observed in any Bi-filled composites. In addition, the thermal conductivities of PS layers with Bragg structure, including pristine and Bi-filled PS composites, are significantly lower than those of the other two structures. SEM images also demonstrates that Bi greatly improved the mechanical property of PS composites, especially the periodic structures composites. This study firmly demonstrates that Bi-filling in PS with periodic Bragg structure is practical to obtain nanocomposites with low thermal conductivity and improved structural stability. It offers a new dimension to optimize the property of PS for thermoelectric application by pore configuration design and controllable nanowire Bi filling.
研究领域:
材料科学
·
热电材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Peiyan Liu,Meiri Wang,Jing Li,Hongtao Cui,Tao Zeng,Shubin Yang,Huan Wang,Yuanyuan Liu
Rechargeable aqueous Zn//MnO 2 batteries are the promising alternatives to lithium-ion batteries owing to their high safety, high energy density, low cost, and environmental friendliness. However, the unstable MnO 2 cathode causes poor practical energy density and serious capacity fading. To overcome this issue, herein, a unique 2D nanosheets self-supported 3D δ -MnO 2 microflower hierarchical architecture is rationally designed and synthesized by taking advantage of its microwave-absorbing characteristics. The 2D nanosheets with high surface area could expose numerous active sites for ions/electrons transfer. Also, the 3D assembled structure acting as building blocks would ensure structural stability for long-life cycles. Benefiting from these synergistic merits, the δ -MnO 2 microflowers deliver a high capacity of 287.6 mA h g −1 at 0.5 C, an excellent rate capability of 202.7 mA h g −1 at 5 C, and a superior cycling retention of 76.5% over 1000 cycles at 10 C. Furthermore, a storage mechanism of H + /Zn 2+ co-insertion accompanied by the deposition of zinc sulfate hydroxide hydrate is clarified by the aid of ex-situ XRD and SEM technologies. This work provides a new pathway for developing high capacity and long lifespan ZIBs.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）