ACS Applied Materials & Interfaces
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2021
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IF 9.229
Ningning Feng,Bingliang Wang,Zhuo Yu,Yuming Gu,Lili Xu,Jing Ma,Yonggang Wang,Yongyao Xia
Li–CO2 batteries have attracted worldwide attention because of their dual characteristics of high energy density and effective CO2 capture. However, the basic electrochemistry mechanism involved has been unclear, which is mainly confused by the complicated decomposition of organic electrolytes. Herein, water-in-salt (WIS, LiTFSI/H2O 21.0 mol/1 kg) has been explored as a suitable electrolyte for the first time to investigate the reaction mechanism of Li–CO2 batteries with different cathodes (carbon nanotube (CNT) and Mo2C/CNT, respectively). An Mo2C-based Li–CO2 battery with WIS delivers a higher energy efficiency of 83% and a superior cyclability, compared to those of the CNT-based counterpart cell. Through various ex/in situ qualitative/quantitative characterizations, the Mo2C-based Li–CO2 battery with WIS can operate on the reversible conversion of CO2-to-Li2C2O4 ((e–/CO2)ideal = 1) at lower discharge/charge overpotentials, while the CNT-based counterpart cell is based on the formation/decomposition of Li2CO3 ((e–/CO2)ideal ≈ 1.33) at high overpotentials. Such a difference in CO2 reduction products stems from the stronger interaction between Mo2C(101) and Li2C2O4 than that of the CNT and Li2C2O4 based on the density functional theory calculations, resulting in the selective stabilization of the intermediate product Li2C2O4 on the Mo2C surface.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
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2018
·Vol. 6
·期 16
·7088-7098
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IF 9.931
Chao Cui,Zengxi Wei,Gang Zhou,Weifeng Wei,Jianmin Ma,Libao Chen,Chengchao Li
Developing electrode materials with a full conversion reaction is an effective route to break through the capacity barriers, but this goal remains a great challenge. In this work, we report the synthesis of CoSe2 anodes with a quasi-reversible conversion reaction by uniformly encapsulating CoSe2 nanoparticles in nitrogen-doped carbon nanofibers (CoSe2/N-CNFs). The space-confined effect of CNFs effectively inhibits pulverization and amorphization of CoSe2 during charge and discharge and thus remarkably ensures the integrity of the crystal structure. Meanwhile, pseudocapacitive contributed by the size effect of CoSe2 nanodots and excellent conductivity due to doped nitrogen heteroatoms give the electrode outstanding electrochemical properties. When used as an anode, the CoSe2/N-CNFs achieved a reversible capacity of 371.8 mA h g−1 after 500 cycles at 0.2 A g−1. Even at a high current density of 2 A g−1, the discharge capacity of the CoSe2/N-CNFs still reached 308 mA h g−1 after 1000 cycles with excellent rate performance. The first principles calculations demonstrate that the heterointerfaces between CoSe2 and nitrogen-doped carbon can significantly enhance the stability of the structure and improve the storage/diffusion capability of Na+. Moreover, ex situ high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) reveal that the unique structure enables quasi-reversible crystalline-phase transformation of CoSe2, which leads to the superior cycling stability of the battery with high capacity retention.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Energy & Environmental Materials
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2021
·Vol. 6
·期 1
·e12255
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IF 15.122
Zhenzhen Liu,Haibo Li
The “battery type” inorganic electrode has been demonstrated the highly efficient sodium ion intercalation capacity for capacitive deionization. In this work, the CoMn 2 O 4 (CMO) microspheres with porous core-shell structure are prepared via co-precipitation and followed by annealing. The effects of annealing temperatures on the morphology, pore structure, valence state, and electrochemical behavior of CMO are explored. As electrode for capacitive deionization, the salt removal capacity and current efficiency of optimized AC || CMO device reaches up to 60.7 mg g −1 and 97.6%, respectively, and the capacity retention rate is 74.1% after 50 cycles. Remarkably, both the in-situ X-ray diffraction and ex-situ X-ray diffraction analysis features that the intercalation/de-intercalation of sodium ions are governed by (103) and (221) crystal planes of CMO. Accordingly, the density functional theory calculations realize that the adsorption energies of Na + onto (103) and (221) crystal planes are higher than that of any other crystal planes, manifesting the priorities in adsorption of sodium atoms. Furthermore, the X-ray photoelectron spectra of pristine and post-CMO electrode highlights that the reversible conversion of Mn 3+ /Mn 4+ couple is resulted from the intercalation/de-intercalation of Na + , while this is irreversible for Co 3+ /Co 2+ couple. Beyond that, the CMO electrode has been proven the selectivity removal of Na + over K + and Mg 2+ in a multi-cation stream.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2018
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IF 6.14
Yunlei Shi,Dazhen Xiong,Zhiyong Li,Huiyong Wang,Yuanchao Pei,Yongkui Chen,Jianji Wang
Emulsion inversion has great potential in applications such as materials science, chemical reactions, and drug delivery. Therefore, developing a simple and green approach to control emulsion inversion is highly desirable. Herein an octyl- and bis(2-hydroxyethyl)-3-amino-bifunctionalized silica microsphere (SM-O-BIS) is designed, prepared, and used to fabricate a Pickering emulsion. It is found for the first time that this Pickering emulsion can be easily and reversibly inverted from water-in-oil (w/o) to oil-in-water (o/w) by alternate bubbling of CO2 and N2 at room temperature and atmospheric pressure. The molar ratio of trimethoxyoctylsilane to bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane on the surface of silica is important for the emulsion inversion. This unique inversion can be recycled multiple times without any deterioration. By utilizing the emulsion inversion strategy, encapsulation and release of curcumin molecules have been actualized on demand. The possible mechanism of emulsion inversion is also investigated by measuring zeta potential, water contact angle, 13C NMR spectroscopy, and FT-IR spectroscopy. It is shown that a significant and reversible change in hydrophilicity/hydrophobicity of SM-O-BIS is the driving force for such a CO2/N2-triggered inversion.
研究领域:
材料科学
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化学工程
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药物递送
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）