Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 11
·6329-6340
·
IF 10.7
Bingjie Wen,Nizao Kong,Min Huang,Liqin Fu,Yexin Tian,Zhixiao Liu,Zhongchao Wang,Lezhi Yang,Fei Han
A single two-dimensional material often struggles to satisfy all the performance requirements of electrode materials for sodium-ion batteries. However, constructing a hierarchical heterogeneous two-dimensional stacking structure can effectively combine the advantages of multiple materials and make up for the insufficiency of a single element. This work applied a pre-intercalation–sulphuration concept and liquid-phase coating modification by constructing a hierarchical nano-flake/micro-lamellar complex structure. In this composite material, MoS2 nanosheets and V2C MXene layers overlap and interact to prevent nanoparticle agglomeration and micron flakes collapse simultaneously. The MoS2/MXene hierarchical structure is sandwiched between ultrathin and dense carbon layers to form a multifaceted conductive skeleton and a twofold protection mechanism. The coating reduces the electrolyte contact area and prevents the escape of polysulfide byproducts. Accordingly, the designed MSVC@C demonstrates superior Na+ storage capacities (612.4 mA h g−1 at 0.5 A g−1 after 600 cycles) and outstanding rate performance (304.42 mA h g−1 at 10 A g−1). Experimental results and theoretical calculations verify that the MoS2 and V2C heterostructure promotes the electrochemical performance owing to the better electronic conductivity and lower ion diffusion energy barrier. Moreover, this structure optimization strategy applies to various MXene guests (e.g., V2C and Nb2C) to prepare a variety of hierarchical nano–micro structures that are expected to be promising two-dimensional electrode materials for SIBs with application prospects in the future.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITE INTERFACES
·
2019
·
IF 2.025
Xueyi Zhu,Shuling Shen,Zhihong Tang,Junhe Yang
Ti3+-doped TiO2@C nanorods were prepared through a facile hydrothermal process. Na2Ti3O7 ultralong nanotubes and glucose were used as TiO2 precursor and carbon (C) source, respectively. During hydrothermal treatment, the hydrolysis of Na2Ti3O7 and polymerization of glucose induced the formation of TiO2 nanorods with a coating of carbon complex. At the same time, a part of Ti4+ was reduced to Ti3+ due to the rich hydroxyl groups in glucose. After calcination, an ultrathin carbon shell was formed on the surface of TiO2 nanorods. In this prepared composite, Ti3+ self-doped TiO2 nanorods work as photosensitizer to harvest solar energy to generate electron-hole pairs, the tight-binding interface between TiO2 nanorods and carbon shell works as electron transportation path, and the ultrathin carbon shell acts as electrons trapped and accumulated site. Photocatalytic test results indicate that Ti3+-doped TiO2@C nanorods exhibit higher activity and stability than TiO2 for photodegradation of methylene blue under visible light.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
ENVIRONMENT INTERNATIONAL
·
2020
·
IF 7.577
Song Li,Jingchun Tang,Qinglong Liu,Xiaomei Liu,Bin Gao
Nano zero-valent iron (nZVI) and its composite materials have been extensively studied in the field of environmental remediation. However, the oxidation and agglomeration of nZVI limits the large-scale application of nZVI in environmental remediation. This study developed a two-step method to prepare stable carbon-coated nZVI (Fe 0 @C) which combined hydrothermal carbonization and carbothermal reduction methods and used glucose and iron oxide (Fe 3 O 4 ) as precursors. When the carbothermal reduction temperature was 700 °C and the elemental molar ratio of carbon to iron was 22:1, stable Fe 0 @C can be generated. The nZVI particles are encapsulated by mesoporous carbon and embedded in the carbon spheres. The unique structure of carbon coating not only inhibits the agglomeration of nZVI, but also makes nZVI stable in air for more than 120 days. Not only that, the as-synthesized Fe 0 @C exhibited high catalytic activity toward the degradation of 4-chlorophenol (4-CP) by activating persulfate. Different from conventional nZVI catalysts in generation of sulfate radicals, Fe 0 @C selectively induced hydroxyl radicals for 4-CP degradation. Moreover, Fe 0 @C has been shown to efficiently degrade 4-CP by using the dissolved oxygen in water to form hydroxyl radicals. This study not only provides a simple, green method for the preparation of stabilized nZVI, but also provides the possibility of large-scale application of nZVI in the field of environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2021
·
IF 4.051
Yuanbo Tan,Mingjie Yi,Zhenye Zhu,Xueting Zhang,Ke Qin,Jiaheng Zhang,Rongshu Zhu
Herein, a mesh carbon-coated MoSe 2 /Mo 2 CT x hybrid material (MoSe 2 /Mo 2 CT x @C) is proposed as an effective catalyst for electrochemical hydrogen evolution reaction (HER). On one hand, the highly conductive Mo 2 CT x substrate enhanced charge transfer ability and effectively prevented the agglomeration of MoSe 2 nanosheets to expose abundant active sites. On the other hand, the carbon coating layer further improved the conductivity and effectively prevented Mo 2 CT x from being oxidized in the environment. Consequently, the unique MoSe 2 /Mo 2 CT x @C hybrid material exhibited excellent HER performance. Specifically, the MoSe 2 /Mo 2 CT x @C catalyst only required an overpotential of 108.3 mV to reach a current density of 10 mA cm −2 and displayed excellent durability under long-term cycling in acidic solution. This research highlights the potential applications of MXene-based composite materials in the energy field.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2018
·Vol. 24
·期 49
·12932-12937
·
IF 5.16
Guozhen Zhu,Qing Li,Renchao Che
Graphical On the ball : The high charge/discharge voltage (1.65 V), long life span, and excellent reversibility of TiNb 2 O 7 have led to its use as an anode for lithium ion batteries. In order to overcome its inherent poor electronic conductivity, it is herein formed as hollow spheres, and coated with carbon, resulting in a much-improved anode performance. TiNb 2 O 7 , with high charge/discharge voltage (1.65 V), long life span, and excellent reversibility has become a new anode material for lithium ion batteries in recent years. However, the inherent poor electronic conductivity strictly limits its practical applications. Herein, we report for the first time hollow TiNb 2 O 7 @C spheres, with carbon spheres as sacrificial template. The special hollow structure can effectively relieve the volume expansion during the repeated process of charging/discharging. The conductivity of hollow TiNb 2 O 7 spheres can be greatly improved by the carbon layers uniformly coated outside the surface of TiNb 2 O 7 spheres. Besides, the particle aggregation can be conspicuously suppressed by the uniformly coated carbon layers. As a result, hollow TiNb 2 O 7 @C spheres show a prominent charge/discharge capacity of 282.6/283.8 mAh g −1 after 100 cycles at 0.25 C (1 C=388 mA g −1 ), revealing the excellent cycle performance and high reversible capacity. Meanwhile, the charge/discharge capacity of 157.5 and 157.9 mAh g −1 can be maintained at 10 C after 10 cycles. The facial synthetic method can be extended to prepare various materials with volume expansion during repeated charging/discharging process.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Chao Wang,Shiheng Li,Yuyao Han,Zhenda Lu
A novel structure of a carbon-coated LiMnPO4 microcluster through emulsion-based self-assembly has been fabricated to yield a high-performance battery cathode. In this rational design, nanosized LiMnPO4 plates are assembled into microclusters to achieve a dense packing and robust interparticle contact. In addition, the conductive carbon framework wrapping around these clusters functions as a fast electron highway, ensuring the high utilization of the active materials. The designed structure demonstrates enhanced specific capacity and cycling stability in lithium-ion batteries, delivering a discharge capacity of 120 mAh g–1 after 200 cycles at 0.2 C. It also shows a superior rate capability with discharge capacities of 139.7 mAh g–1 at 0.05 C, 131.7 mAh g–1 at 0.1 C, and 99.2 mAh g–1 at 1 C at room temperature.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Weidong Nie,Yuanyuan Liu,Jing Li,Meiri Wang,Kaihua Liu,Hongtao Cui
In this work, we choose NiO as an example of battery-type materials. We reveal that the electrochemical destabilization of NiO is attributed to the particle merging caused by electrochemical Ostwald ripening. Based on this understanding, we construct a particulate NiO-composed 2D structure coated by a thin carbon layer. Due to the prevention of particle merging by carbon coating and the increase of electrical and ionic conductivities by oxygen vacancies, this structure presents high electrochemical performance and an ultra-long cycling life. This carbon-coated 2D structure of NiO has a high specific capacity of 437.8 C g −1 at low current density and presents excellent high-rate performance (capacity retention of 66% at high current density). It exhibits ultra-high electrochemical stability (capacity retention of 93.5% after an ultra-long cycling of 100,000 cycles). This work demonstrates the success of carbon modification strategy for NiO, also may provide a significant outlet for transforming low-performance battery-type materials into high-performance materials.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 32
·15755-15761
·
IF 9.931
Sainan Luo,Pengcheng Zhang,Tao Yuan,Jiafeng Ruan,Chengxin Peng,Yuepeng Pang,Hao Sun,Junhe Yang,Shiyou Zheng
Spinel lithium titanate (Li4Ti5O12, LTO) is one of the most appealing anode materials for lithium-ion batteries (LIBs) due to its long cycle life and high safety performance. However, its low intrinsic electronic conductivity limits its high rate capability. Herein, we develop a novel one-pot in situ molecular self-assembly approach to prepare a dual N- and anatase-TiO2- modified Li4Ti5O12/C nanorod material (NT-LTO/C). Polypyrrole (PPy), as a pivotal carbon and nitrogen source, is introduced to confine the morphology and particle size of the NT-LTO/C anode. Due to the synergistic effects of the multilevel particle structure, uniform carbon coating, N doping, anatase TiO2 pseudopotential effect and such benefits, the NT-LTO/C electrode delivers a high reversible capacity of 196.3 mA h g−1 at 0.5C, and it maintains 105.5 mA h g−1 even at an ultrahigh rate of 100C with progressive cycling of more than 3000 cycles. In addition, the three electrode pouch full-cell shows much smaller polarization than the pristine one. This novel and facile molecular self-assembly method has broad advanced functional material applications including for ceramics, polymer/carbon-based metal alloys and inorganic non-metallic materials.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2020
·Vol. 49
·期 4
·2529-2538
·
IF 1.774
Zhang Pengfei,Liu Yanxia,Chai Fengtao,Fan Yameng,Hou Aolin
Li 4 Ti 5 O 12 (LTO) composites modified with carbon nanotubes (CNTs) and carbon coating (LTO@C/CNTs) were synthesized by a simple solid-state reaction. The carbon-coated layers reduce the growth of the primary particles, inhibit interface side reactions and increase electron conductivity, so CNTs-modified LTO can form a conductive network and improve the diffusion path of lithium ions. The LTO@C/CNTs composites show a high-rate capability (150 mAh g −1 at 10 C, 145 mAh g −1 at 20 C) with good cycling performance (90.1% and 82.8% capacity retentions after 1000 cycles at 10 C and 20 C, respectively). In addition, superior electrochemical performance is also demonstrated in a full cell with a LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode and LTO@C/CNTs anode (97.1% capacity retentions after 200 cycles at 1 C). The carbon coating and CNTs-modified in LTO can reduce the polarization of potential difference and charge-transfer resistance, improve the diffusion coefficient of lithium ions, and lead to high rate performance and cycle stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2023
·
IF 10.9
Bin Wang,Yaotian Yan,Jinghuang Lin,Yifei Cai,Jian Cao,Junlei Qi
Efficient multi-path heat dissipation is urged to be designed for balancing the heat density generated in highly integrated electronic devices. Herein, aluminum foam/carbon composites were fabricated by chemical bath and annealing method to realize the effect of strengthening the effective thermal conductivity while retaining the convective heat transfer characteristics of the porous structure . The results show that the continuous and high crystalline carbon coating can be obtained in the optimized composites prepared with 350 g dopamine addition at 600 °C annealing temperature. When compared with amorphous carbon , the phonons in crystalline carbon can carry more energy during the heat transport in terms of high phonons density of states, and their scattering behavior can be alleviated. A smaller temperature gradient is further established in the system. Hence, a desirable thermal conductivity, 21.44 W m −1 K −1 , is obtained in the optimized composites, which is almost 3 times that of pristine aluminum foam (7.67 W m −1 K −1 ). Additionally, the remarkable cooling efficiency of 24.71% in comparison to other studies, suggests that aluminum foam/carbon composites hold great potential as thermal management materials in addressing the issue of intense heat generation.
研究领域:
材料科学
·
热管理工程
✓ 已验证
产品关联
DOI
高影响因子
Applied Materials Today
·
2022
·
IF 8.663
Wei Jiao,Lili Zhang,Ruiquan Yang,Jing Ning,Lei Xiao,Yifan Liu,Jianyi Ma,Nasir Mahmood,Xian Jian
Increasing visible light absorption and constructing an active surface for TiO 2 have long been pursued to obtain high photocatalytic activities. Modifying TiO 2 at an atomic scale is desirable to optimize its surface state and band structure but remains a huge challenge. Herein, we developed an ultrasmall (∼5 nm) visible-light-responsive TiO 2 photocatalyst with a novel hybrid structure (TiO 2 /C) through a chemical vapor deposition process on large scale. Environmental in-situ transmission electron microscope studies confirmed the anatase TiO 2 with a monolayer carbon shell in a hybrid structure. The resulted structure possesses narrowed bandgap 2.83 eV, favoring the enhanced visible-light-responsive photocatalytic activity. Density functional theory (DFT) simulations confirm the tunable mechanism of carbon-induced localized energy band within the bandgap of TiO 2 . As a physical barrier without turning TiO 2 black, the monolayer carbon shell stabilizes Ti 3+ inside TiO 2, facilitates the separation of photo-induced carriers and enriches abundant absorbing sites of target pollutants. Consequently, the TiO 2 /C exhibits outstanding photocatalytic performance in both photoelectrochemical water oxidation and dye degradation under visible light besides superior activity for hydrogen evolution under simulated sunlight irradiation. This design proved a meaningful strategy in obtaining visible-light-responsive photocatalysts with a stable active surface for industrial application.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Energy & Environmental Science
·
2024
·Vol. 17
·期 14
·5147-5161
·
IF 32.4
Qingfeng Fu,Wang Zhou,Peng Gao,Hongliang Dong,Shi Chen,Changling Fan,Jilei Liu
Fluorophosphate compounds are an important class of cathode materials; however, the one-step synthesis of phase-pure fluorophosphate compounds in a well-controlled manner remains challenging owing to the facile volatilization of fluorine during heat treatment. Herein, the rapid, facile, and scalable preparation of phase-pure fluorophosphates (e.g. KVPO4F) was successfully realized via a one-step solid-state reaction through the addition of PVDF, which served as an effective fluorine-compensating, vanadium-reducing, and in situ carbon-coating agent. In-depth mechanistic study showed that carbene (:CH2) generated upon PVDF decomposition could be easily recombined to form a ˙CH2(CH2)nCH2˙ alkyl biradical, and both were able to catalyze C–F bond breakage in fluorocarbon gases (C2F4) and therefore plays a pivotal role in promoting the formation of phase-pure fluorophosphate. The resultant cathode enabled a superior potassium-storage capability, including high specific capacity, excellent rate capability, and good cycling stability. The generality of the as-proposed synthetic strategy was also validated through the successful preparation of other fluorophosphate compounds.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）