A robust spring-like lamellar VO/C nanostructure for high-rate and long-life potassium-ion batteries. Issue 45 (10th November 2020)

• Record Type: Journal Article
• Authors: Lu, Jian; Wang, Changlai; Xia, Guoliang; Tong, Huigang; Yang, Yang; Zhu, Dequan; Chen, Qianwang
• Is Part Of: Journal of materials chemistry. Volume 8:Issue 45(2020)
• Page Start: 23939
• Page End: 23946
• Publication Date: 2020-11-10
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0ta08845e
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A unique spring-like lamellar VO/C nanostructure exhibits excellent stability and outstanding rate capability for potassium-ion batteries. Abstract : Metal oxides usually exhibit low reversible capacity, inferior rate capability and limited lifespan for potassium-ion batteries due to the large radius of K + . Herein, a spring-like lamellar nanostructure composed of VO nanoparticles embedded in amorphous carbon layers (VO/C) has been rationally designed. It exhibits a large capacity of 345 mA h g −1 at 0.1 A g −1 after 400 cycles, excellent stability of 241 mA h g −1 at 1 A g −1 over 1000 cycles and outstanding rate performance of 104 mA h g −1 at 15 A g −1, superior to most reported transition metal oxides for PIBs. The in situ formed lamellar VO/C nanostructure can accommodate the volume variation during cycling. Density functional theory (DFT) calculations reveal that the hybrid VO/C structure significantly increases the electronic states at the Fermi level, thus improving the electronic conductivity, and reduces the K + diffusion barrier (from 1.95 eV of VO to 1.19 eV), which contributes to its large capacity and superior rate performance. A PIB full cell exhibits 168 mA h g −1 at 2 A g −1 and 80% capacity retention over 500 cycles. This work provides some insights into the rational design of metal oxide-based anodes for high-performance PIBs.