Chem ( IF 23.5 ) Pub Date : 2018-11-02 , DOI: 10.1016/j.chempr.2018.10.004 Yun-Hai Zhu , Qi Zhang , Xu Yang , En-Yue Zhao , Tao Sun , Xin-Bo Zhang , Sai Wang , Xi-Qian Yu , Jun-Min Yan , Qing Jiang
Potassium-ion batteries (KIBs) are a promising alternative to lithium-ion batteries because of the abundance, low cost, and redox potential of K; however, the significantly larger radius of K+ inevitably destabilizes the crystal structure of the cathode material, impeding the diffusion of K+. Here, to lower the insertion energetics and diffusion barriers of K+, we synthesizedδ-K0.51V2O5 nanobelts (KVOs) with a large interlayered structure and optimized growth orientation by reconstructing the V–O polyhedra of orthorhombic V2O5; these exhibited a high average voltage (3.2 V), high capacity (131 mAh g−1), and superior rate capability even at 10 A g−1. By coupling the electrochemical experiments with theoretical calculations, we found that the excellent K-ion storage performance of KVO is attributed to its large interlayered structure and unique 1D morphology. Additionally, we assembled a full KIB composed of KVO and graphite with high energy and power densities, proving its feasibility as a promising new battery.
中文翻译:
重构正交V 2 O 5多面体,用于K离子电池中的快速离子扩散
钾离子电池(KIBs)是锂离子电池的有前途的替代品,因为K的含量高,成本低且具有氧化还原电位。然而,K +的明显较大的半径不可避免地使阴极材料的晶体结构不稳定,从而阻碍了K +的扩散。这里,为了降低插入能量学和K的扩散阻挡层+,我们synthesizedδ-K 0.51 V 2 ø 5个纳米带(KVOs)与通过重建正交V的V-0多面体大层间结构和优化的生长取向2 ö 5 ; 它们表现出高的平均电压(3.2 V),高容量(131 mAh g -1),甚至在10 A g -1时也具有出色的倍率性能。通过将电化学实验与理论计算相结合,我们发现KVO出色的K离子存储性能归因于其较大的层间结构和独特的1D形态。此外,我们组装了由KVO和石墨制成的具有高能量和功率密度的完整KIB,证明了其作为有前途的新型电池的可行性。