Yazar "Zhang, Baichao" seçeneğine göre listele

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    Fabrication of a Stable and Highly Effective Anode Material for Li-Ion/Na-Ion Batteries Utilizing ZIF-12
    (Wiley-V C H Verlag Gmbh, 2024) Bugday, Nesrin; Wang, Haoji; Hong, Ningyun; Zhang, Baichao; Deng, Wentao; Zou, Guoqiang; Hou, Hongshuai
    Transition metal selenides (TMSs) are receiving considerable interest as improved anode materials for sodium-ion batteries (SIBs) and lithium-ion batteries (LIBs) due to their considerable theoretical capacity and excellent redox reversibility. Herein, ZIF-12 (zeolitic imidazolate framework) structure is used for the synthesis of Cu2Se/Co3Se4@NPC anode material by pyrolysis of ZIF-12/Se mixture. When Cu2Se/Co3Se4@NPC composite is utilized as an anode electrode material in LIB and SIB half cells, the material demonstrates excellent electrochemical performance and remarkable cycle stability with retaining high capacities. In LIB and SIB half cells, the Cu2Se/Co3Se4@NPC anode material shows the ultralong lifespan at 2000 mAg-1, retaining a capacity of 543 mAhg-1 after 750 cycles, and retaining a capacity of 251 mAhg-1 after 200 cycles at 100 mAg-1, respectively. The porous structure of the Cu2Se/Co3Se4@NPC anode material can not only effectively tolerate the volume expansion of the electrode during discharging and charging, but also facilitate the penetration of electrolyte and efficiently prevents the clustering of active particles. In situ X-ray difraction (XRD) analysis results reveal the high potential of Cu2Se/Co3Se4@NPC composite in building efficient LIBs and SIBs due to reversible conversion reactions of Cu2Se/Co3Se4@NPC for lithium-ion and sodium-ion storage. The Cu2Se/Co3Se4@NPC material, which is synthesized from Cu@ZIF-12, utilizes the advantages of Cu and Co metal complexes to facilitate the storage of lithium and sodium ions. Defect-rich N-doped amorphous carbon (NPC) improves electrical conductivity, and the Cu2Se/Co3Se4@NPC composite material demonstrates remarkable cycle stability while retaining high capacities in LIB and SIB half cells. image
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    Full-Scale Regulation Enabled High-Performance Sodium O3-Type Layered Cathodes
    (Wiley-V C H Verlag Gmbh, 2025) Hong, Ningyun; Zhang, Shuncheng; Li, Jianwei; Wang, Haoji; Huang, Jiangnan; Hu, Xinyu; Zhang, Baichao
    O3-type cathodes hold considerable promise in achieving rapid commercialization due to high energy density. However, severe structural/interfacial deterioration, along with kinetic hindrance, typically resulting in rapid capacity fading and serious safety risk at elevated cut-off voltages. Herein, inspired from solubility limitation of hetero-elements, synchronous surface-to-bulk multifunctionally full-scale modified O3-NaNi1/3Fe1/3Mn1/3O2 is proposed to maintain its state of health (SOH). The perovskite-type CaZrO3 protective layer in situ formed on the surface of primary particles, helps to construct a stable cathode-electrolyte-interphase architecture, mitigate the unexpected interfacial side reactions and prevent transition metal dissolution. Simultaneously, Ca2+ pillars, robust Zr-O bonds and the highly electronegative F- are adequately anchored into ternary lattice sites of Na-TM-O, respectively, thereby reinforcing the TMO6 octahedra and facilitating Na+ diffusion. Notably, the intrinsic lattice strain is effectively alleviated due to an additional intergrowth phase transition of P3-OP2. More impressively, migration of Jahn-Teller distorted Fe4+O6 is further restrained, originating from the strengthened coordination environment under deep-desodiation state. Consequently, as-designed NFM-CZF achieves an impressive rate capability and a remarkable capacity retention of 83.8 % after 300 cycles at 2 C. This elaborate work shed valuable insight into mechanism of regulating internal full Wyckoff-site and external surface structure for sodium-ion batteries with enhanced durability.
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    Manipulating Local Chemistry and Coherent Structures for High-Rate and Long-Life Sodium-Ion Battery Cathodes
    (Amer Chemical Soc, 2024) Wang, Haoji; Chen, Hongyi; Mei, Yu; Gao, Jinqiang; Ni, Lianshan; Hong, Ningyun; Zhang, Baichao
    Layered sodium transition-metal (TM) oxides generally suffer from severe capacity decay and poor rate performance during cycling, especially at a high state of charge (SoC). Herein, an insight into failure mechanisms within high-voltage layered cathodes is unveiled, while a two-in-one tactic of charge localization and coherent structures is devised to improve structural integrity and Na+ transport kinetics, elucidated by density functional theory calculations. Elevated Jahn-Teller [Mn3+O6] concentration on the particle surface during sodiation, coupled with intense interlayer repulsion and adverse oxygen instability, leads to irreversible damage to the near-surface structure, as demonstrated by X-ray absorption spectroscopy and in situ characterization techniques. It is further validated that the structural skeleton is substantially strengthened through the electronic structure modulation surrounding oxygen. Furthermore, optimized Na+ diffusion is effectively attainable via regulating intergrown structures, successfully achieved by the Zn2+ inducer. Greatly, good redox reversibility with an initial Coulombic efficiency of 92.6%, impressive rate capability (86.5 mAh g(-1) with 70.4% retention at 10C), and enhanced cycling stability (71.6% retention after 300 cycles at 5C) are exhibited in the P2/O3 biphasic cathode. It is believed that a profound comprehension of layered oxides will herald fresh perspectives to develop high-voltage cathode materials for sodium-ion batteries.
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    Multivalent Cation Incorporated into Manganese-Iron Based NASICON Cathodes for High Voltage Sodium-Ion Batteries
    (Wiley-V C H Verlag Gmbh, 2024) Zeng, Jingyao; Gao, Jinqiang; Jian, Weishun; Wang, Haoji; Li, Wenyuan; Hong, Ningyun; Zhang, Baichao
    Na4Mn1.5Fe1.5(PO4)(2)P2O7 (NMFPP), with its low cost and high energy density, is essential for accelerating the commercialization of sodium-ion batteries. However, its practical application is limited by serious voltage hysteresis and detrimental Jahn-Teller distortions. Herein, a high operating voltage and superior stable Nb-doped NMFPP with fewer intrinsic anti-site defects are elaborately designed by the reconstruction of the crystal lattice and electronic distribution. By introducing higher charge density Nb & horbar;O bonds, the lengths of Mn-O bonds are shortened, enhancing lattice stability. As a result, the lattice volume contracted during Na+ extraction/insertion is decreased with niobium-modified Na-4(Mn0.5Fe0.5)(2.94)Nb-0.06(PO4)(2)P2O7, mitigating lattice distortion from the Jahn-Teller effect and increasing the capacity retention after 1000 cycles from 57.5% to 82.3%. More importantly, the delayed effect of Mn2+ involvement in redox reactions is significantly reduced, raising the average operating voltage from 3.32 to 3.64 V and increasing the overall energy density by 13%. This study opens new avenues to develop advanced sodium-ion battery cathode materials with high energy density and long calendar life for energy storage.