JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2023
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IF 10.9
Zhi-Xiong Huang,Xue-Li Zhang,Xin-Xin Zhao,Hong-Yan Lü,Xin-Yi Zhang,Yong-Li Heng,Hongbo Geng,Xing-Long Wu
Sodium-ion batteries (SIBs) are proved as one of the most acceptable candidates for replacing lithium-ion batteries in some fields by virtue of a similar “rocking chair” mechanism and the abundance of sodium. The voltage, rate performance, and energy density of these batteries are mainly determined by the cathodes. Hence, a Li-Ni-Co co-substituted P2-Na 0.67 [Li 0.1 (Mn 0.7 Ni 0.2 Co 0.1 ) 0.9 ]O 2 (NLMNC) with ribbon superstructure is prepared with the aim of multi-ion synergistic modification. Owing to the addition of Ni and Co, the Jahn–Teller distortion of Mn can be suppressed corresponding with the improved structural stability, and a little bit of oxygen redox activities is triggered. When with the substitution of 10% Li, the X-ray diffraction (XRD) peaks of NLMNC show the ribbon superstructure at about 21° and 22°. The smooth charge/discharge profiles of the NLMNC cathode exhibit the solid-solution reaction. In addition, the platform at high voltage disappears corresponding with the existing oxygen redox activities being suppressed which may be related to the ribbon superstructure and the promotion of the Ni redox. Such NLMNC cathode can deliver a reversible discharge capacity of 123.5 mA h g –1 at 10 mA g –1 . Even if the current density increases to 500 mA g –1 , a reversible discharge capacity of 112.8 mA h g –1 still can be obtained. The distinguished cycling stability is related to the reversible migration of Li + between the metal oxide layer and the interlayer and low volume change during cycling. It is also needing to be mentioned that the capacity retention of NLMNC cathode is about 94.4% (based on the highest discharge capacity) after 100 cycles. This work presents an effective route to develop high-performance cathodes for SIBs.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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IF 9.7
YuKai Hua,MingPei Tan,Ming Liu,Xiao Yu,Donghai Wang,Yong Liu
P2-type layered metal oxides are promising cathode materials for Na-ion batteries (NIBs), but they suffer from Na + /vacancy ordering and P2-O2 phase transitions during charge–discharge processes, resulting in rapid capacity decay and poor rate performance. In this study, a non-equimolar five-component medium-entropy strategy was employed to design a Na 0.67 Ni 0.19 Cu 0.07 Zn 0.07 Mn 0.60 Ti 0.07 O 2 (NNCZMT) material. Unlike equimolar high-entropy designs, Ni and Mn remain as the main components, with Ni providing high capacity through the Ni 2+ /Ni 4+ redox couple and Mn stabilizing the P2 structure. The introduction of Cu 2+ , Zn 2+ , and Ti 4+ , which have slightly larger ionic radii and the same valence states as Ni 2+ and Mn 4+ , respectively, allows for mutual substitution, synergistically promoting a solid-solution reaction and excellent Na + diffusion kinetics. The NNCZMT electrode delivers a high reversible capacity of 110 mAh g −1 at 10 mA g −1 , an initial Coulombic efficiency of 96.8 %, remarkable cycling stability (94.7 % capacity retention after 100 cycles at 200 mA g −1 ), and excellent rate performance (57.2mAh g −1 at 2000 mA g −1 ).
研究领域:
材料科学
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能源存储技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Yang Jiang,Wenhui Li,Kun Luo
P2-type layered oxide materials have attracted considerable interest because of their high safety and low cost. However, P2-type materials suffer from complicated Na+/vacancy ordering and undesirable phase transitions, resulting in staircase-like electrochemical curves accompanied by fast capacity fading and poor rate performance. A P2-type layered cathode material with high-entropy cation configurations, Na0.85Li0.08Mg0.04Ni0.22Al(B)0.04Mn0.62O2 (HEO), is designed and successfully synthesized in this work. The presence of various metal ions in the transition metal layers imposes an influence on the Na+/vacancy arrangement in the alkali layers, as evidenced by the change of the interlayer distance associated with the electrostatic repulsion. HEO exhibits a smooth electrochemical process without obvious voltage plateaus within 2.0–4.3 V and delivers a reversible capacity of 115 mA h g–1. Structural characterizations indicate that HEO undergoes a complete solid–solution reaction without undesirable phase transitions over the whole voltage range, which facilitates ultrasmall volume variation (0.6%) and fast Na+ ion diffusion (10–9 cm2 s–1) in the electrochemical process. The HEO material therefore shows excellent electrochemical performances with high rate performance (91 mA h g–1 at a current density of 480 mA g–1) and high capacity retention in a wide temperature range from −45 to 55 °C (after 100 cycles, the batteries show 80% capacity retention at 55 °C, 87% at room temperature, and 92% at −45 °C). The results described in this work demonstrate a method to inhibit the complicated staircase-like electrochemical profiles induced by either Na+/vacancy ordering or undesirable P–O phase transitions in P2-type oxide cathode materials and a useful strategy for enhancing the electrochemical performance of P2-type cathode materials for all-climate sodium-ion batteries.
研究领域:
材料科学
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电化学
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电池技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
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2025
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IF 5.6
Xiang Cai,Shijun Tang,Zi-min An,Qiyao Shao,Kuixuan Zhang,Huan Liu
Layered molybdenum trioxide (α-MoO 3 ) storing protons exhibits a high theoretical capacity and extraordinary rate capability and can be used as a reliable anode material for aqueous proton batteries. But a severe dissolution issue during operation always results in rapid failure in battery performance. Herein, a bifunctional molecular crowding electrolyte was engineered to address this issue. The high-concentration inert polymer, polyethylene glycol 400, reduces the free water activity of the electrolyte and the low-concentration solute, trifluoromethanesulfonic acid, forms a proton-rich electrolyte environment under such a water-poor condition thanks to its intrinsic superacidity, both of which favour the reverse shift of the dissolution equilibrium, and with the latter enabling the electrolyte with high ion conductivity as well. Thus, the α-MoO 3 electrode in the above electrolyte shows a longer lifespan without sacrificing its rate capability. The analysis on charge storage mechanisms by X-ray powder diffraction technique demonstrates that α-MoO 3 undergoes bare proton-involved multistep two-phase and solid-solution reactions, where only the two-phase reaction between hydrogen molybdenum bronze II and III phases and the solid-solution reactions of themselves are reversible.
研究领域:
材料化学
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电化学
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能源存储
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无机化学
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固体化学
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电池技术
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功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）