1. |
- Aristote, Nkongolo Tshamala, et al.
(författare)
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Methods of improving the initial Coulombic efficiency and rate performance of both anode and cathode materials for sodium-ion batteries
- 2022
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Ingår i: Chinese Chemical Letters. - : Elsevier BV. - 1001-8417 .- 1878-5964. ; 33:2, s. 730-742
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Tidskriftsartikel (refereegranskat)abstract
- Sodium-ion batteries (SIBs) have gained more scientists’ interest, owing to some facts such as the natural abundance of Na, the similarities of physicochemical characteristics between Li and Na. The irreversible Na+ ions consumption during the first cycle of charge/discharge process (due to the formation of the solid electrolyte interface (SEI) on the electrode surface and other irreversible reactions) is the factor that determines high performance SIBs and largely reduces the capacity of the full cell SIBs. Thus, the initial coulombic efficiency (ICE) of SIBs for both anode and cathode materials, is a key parameter for high performance SIBs, and the point is to increase the transport rate of the Na+ ions. Therefore, developing SIBs with high ICE and rate performance becomes vital to boost the commercialization of SIBs. Here we provide a review on the methods to improve the ICE and the rate performance, by summarizing some methods of improving the ICE and rate performance of the anode and cathode materials for SIBs, and end by a conclusion with some perspectives and recommendations.
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2. |
- Di, Andi, 1992-, et al.
(författare)
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Tunable Ordered Nanostructured Phases by Co-assembly of Amphiphilic Polyoxometalates and Pluronic Block Copolymers
- 2023
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Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 23:5, s. 1645-1651
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Tidskriftsartikel (refereegranskat)abstract
- The assembly of polyoxometalate (POM) metal–oxygen clusters into ordered nanostructures is attracting a growing interest for catalytic and sensing applications. However, assembly of ordered nanostructured POMs from solution can be impaired by aggregation, and the structural diversity is poorly understood. Here, we present a time-resolved small-angle X-ray scattering (SAXS) study of the co-assembly in aqueous solutions of amphiphilic organo-functionalized Wells-Dawson-type POMs with a Pluronic block copolymer over a wide concentration range in levitating droplets. SAXS analysis revealed the formation and subsequent transformation with increasing concentration of large vesicles, a lamellar phase, a mixture of two cubic phases that evolved into one dominating cubic phase, and eventually a hexagonal phase formed at concentrations above 110 mM. The structural versatility of co-assembled amphiphilic POMs and Pluronic block copolymers was supported by dissipative particle dynamics simulations and cryo-TEM.
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3. |
- Li, Jiayang, et al.
(författare)
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Electrochemical Zintl Cluster Bi22− induced chemically bonded bismuth / graphene oxide composite for sodium-ion batteries
- 2022
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Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686 .- 1873-3859. ; 413
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Tidskriftsartikel (refereegranskat)abstract
- Bismuth, a promising attribute for sodium-ion batteries, which have been attracting significant attention owing to their advantages of high volumetric capacity and suitable operating potential. However, most traditional Bi-based materials are suffered from pulverization and fracture of the electrodes caused by dramatic volume variation, consequently diminishing the cycle stability. Herein, in this work, bismuth embedded within graphene oxide matrices have been obtained by utilizing a novel and efficient electrochemical method. Through the strong reducing properties of Zintl clusters Bi22−, GO is partially reduced to generate reduced graphene oxide with better electrical conductivity. Simultaneously, Bi is strongly loaded on the GO through Bi-O-C bonding, which can form Bi2O22+ with excellent ionic conductivity. Moreover, the volume expansion of Bi during sodiation can be effectively buffered in the GO matrices. As a result, this Bi/GO composite exhibits excellent electrochemical performances in sodium-ion batteries (SIBs), including a high specific capacity of 258 mAh g−1 at 10 A g−1 and an excellent cycle stability with high retained capacity of 315 mAh g−1 after 500 cycles at 2 A g−1. This work paves the way to prepare designated promising electrode materials for high-performance SIBs, and thoroughly understands mechanism of electrochemical methods for preparing materials.
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4. |
- Ni, Lianshan, et al.
(författare)
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Challenges and Strategies towards Single-Crystalline Ni-Rich Layered Cathodes
- 2022
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Ingår i: Advanced Energy Materials. - : Wiley. - 1614-6832 .- 1614-6840. ; 12:31
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Forskningsöversikt (refereegranskat)abstract
- The ever-increasing energy density requirements in electric vehicles (EVs) have boosted the development of Ni-rich layered oxide cathodes for state-of-the-art lithium-ion batteries. Nevertheless, the commercialization of polycrystalline Ni-rich cathodes (PCNCs) is hindered by the severe performance degradation and safety concerns that are tightly related to its particle cracking during cycling. Single-crystalline Ni-rich cathodes (SCNCs) with eliminated grain boundaries and high mechanical strength have recently attracted extensive attention owing to their superior structural and cycling stability, which present high crack resistance during electrochemical operation. Various articles have focused on the trial-and-error synthesis and modifications of SCNCs, as well as the comparison of performances and mechanisms with PCNCs. However, there has been much less effort in systematic analysis and summary to reveal their key challenges, controversies, and the corresponding primary causes. In this review, the advantages and debates in structural and electrochemical properties of SCNCs over PCNCs are summarized to provide fundamental understanding of SCNCs. Then the current practical issues and challenges are comprehensively discussed from the viewpoints of both academia and industry, as well as the proposed modification strategies and underlying mechanisms for SCNCs. The outlook and perspectives are further given to facilitate the commercial applications of SCNCs in high-performance EVs.
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5. |
- Wang, Kai, et al.
(författare)
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Zinc anode based alkaline energy storage system: Recent progress and future perspectives of zinc–silver battery
- 2024
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Ingår i: Energy Storage Materials. - 2405-8297. ; 69
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Forskningsöversikt (refereegranskat)abstract
- Rechargeable zinc-based batteries have come to the forefront of energy storage field with a surprising pace during last decade due to the advantageous safety, abundance and relatively low cost, making them important supplements of lithium-ion batteries. As a significant role in zinc-based batteries, zinc-silver battery owns the advantages of high specific energy density, stable working voltage, high charging efficiency, safety and environmental friendliness, and it has been widely used in military such as in aerospace, deep water manned and civil field such as energy supply for watch and hearing aid. However, it is still suffering from a few drawbacks such as unsatisfactory cycle life, low utilization of the cathode. This review introduces the basic principles of zinc-silver batteries and elaborates the battery configurations aiming to understand its working mechanisms as well as the related issues. Most importantly, the very recent research updates and the concerns have arisen in the development are summarized from conventional cell to flexible device and hybrid device. Finally, the challenges and perspectives of zinc-silver batteries are further prospected to give a broad idea to readers new in the area and trigger inspirations for motivated researchers to further widen the utilization of silver-zinc batteries.
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6. |
- Yang, Junhua, et al.
(författare)
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South Asian black carbon is threatening the water sustainability of the Asian Water Tower
- 2022
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Long-range transport of black carbon from South Asia to the Tibetan plateau and its deposition on glaciers directly enhances glacier melt. Here we find South Asian black carbon also has an indirect effect on the plateau’s glaciers shrinkage by acting to reduce the water supply over the southern Tibetan plateau. Black carbon enhances vertical convection and cloud condensation, which results in water vapor depletion over the Indian subcontinent that is the main moisture flux source for the southern Tibetan plateau. Increasing concentrations of black carbon causes a decrease in summer precipitation over the southern Tibetan plateau, resulting in 11.0% glacier deficit mass balance on average from 2007 to 2016; this loss rises to 22.1% in the Himalayas. The direct (accelerated melt) and indirect (mass supply decrease) effects of black carbon are driving the glacial mass decline of the so-called “Asian Water Tower”.
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7. |
- Zhang, Shu, et al.
(författare)
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Mitigating the Jahn-Teller distortion driven by the spin-orbit coupling of lithium manganate cathode
- 2022
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Ingår i: Journal of Energy Challenges and Mechanics. - : Elsevier BV. - 2056-9386. ; 72, s. 379-387
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Tidskriftsartikel (refereegranskat)abstract
- Spinel LiMn2O4 is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich sources. However, the wholesale application of LiMn2O4 is predominately plagued by its severe capacity degradation, mainly associated with the innate Jahn-Teller effect. Herein, single-crystalline LiMn2O4 with Eu3+ doping is rationally designed to mitigate the detrimental Jahn-Teller distortion by tuning the chemical environment of MnO6 octahedra and accommodating localized electron, based on the unique aspheric flexible 4f electron orbit of rare-earth metal ions. Notably, the stretching of MnO6 octahedron stemmed from the Jahn-Teller effect in Eu-doped LiMn2O4 is effectively suppressed, confirmed by theoretical calculation. Meanwhile, the structural stability of the material has been significantly enhanced due to the robust Mn–O band coherency and weakened phase transition, proved by synchrotron radiation absorption spectrum and operando X-ray diffraction. The corresponding active cathode manifests superior long-cycle stability after 300 loops at 2C and displays only a 0.011% capacity drop per cycle even at 5C. Given this, this modification tactic sheds new light on achieving superior long-cycle performances by suppressing distortion in various cathode materials.
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