Details

Autor(en) / Beteiligte

• Zhu, Xiangzhen
• Cao, Haijie
• Li, Renjie
• Fu, Qingfeng
• Liang, Guisheng
• Chen, Yongjun
• Luo, Lijie
• Lin, Chunfu
• Zhao, Xiu Song

Titel

Zinc niobate materials: crystal structures, energy-storage capabilities and working mechanisms

Ist Teil von

• Journal of materials chemistry. A, Materials for energy and sustainability, 2019, Vol.7 (44), p.25537-25547

Ort / Verlag

Cambridge: Royal Society of Chemistry

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• W 5 Nb 16 O 55 is a very promising negative electrode compound for lithium-ion storage owing to its good safety, durable cyclability and high rate performance. However, its commercialization is hindered by its limited capacity and high tungsten cost. Here, we designed a tungsten-free and niobium-rich zinc niobate (Zn 2 Nb 34 O 87 ) with a large capacity (theoretically 389 mA h g −1 ) as a new insertion negative electrode compound. Micron-sized Zn 2 Nb 34 O 87 blocks (Zn 2 Nb 34 O 87 -B) and one-dimensional Zn 2 Nb 34 O 87 nanofibers (Zn 2 Nb 34 O 87 -N) were prepared via a solid-state reaction and electrospinning methods, respectively. Zn 2 Nb 34 O 87 -B and Zn 2 Nb 34 O 87 -N have 3 × 4 × ∞ shear ReO 3 crystal structures of orthorhombic and monoclinic types, respectively. Both the Zn 2 Nb 34 O 87 materials exhibited better electrochemical performance than W 5 Nb 16 O 55 in terms of the capacity, lithium-ion diffusion coefficient, intercalation pseudocapacitive contribution, rate performance, and cyclability. In situ X-ray diffraction characterization demonstrated the excellent structural stability and electrochemical reversibility of Zn 2 Nb 34 O 87 , and revealed that lithium ions were stored in the (010) crystallographic planes. Furthermore, a LiNi 0.5 Mn 1.5 O 4 |Zn 2 Nb 34 O 87 -N full cell exhibited outstanding electrochemical performance, including a large capacity, prominent rate performance, and especially ultra-long cyclability (96.5% capacity retention even after 1000 cycles at 5C). Therefore, Zn 2 Nb 34 O 87 holds great promise as a practical negative electrode compound for large-capacity, cost-effective, rapid, durable and safe lithium-ion storage. Two tungsten-free and niobium-rich Zn 2 Nb 34 O 87 materials with excellent electrochemical reversibility are explored as better anode materials than the famous W 5 Nb 16 O 55 .