Na3V2(PO4)3 nanoparticles confined in functional carbon framework towards high-rate and ultralong-life sodium storage

• Published in: Journal of alloys and compounds Vol. 791; pp. 296 - 306
• Main Authors: Cao, Xiaoyu, Sun, Qiancheng, Zhu, Limin, Xie, Lingling
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 30.06.2019; Elsevier BV
• Subjects: Carbon; Cathodes; Charge transfer; Cycles; Electrical resistivity; Electrochemical impedance spectroscopy; Electrode materials; Energy storage; High-rate capability; Metal-organic frameworks; MIL-101(V); Na3V2(PO4)3/carbon cathode composites; Nanoparticles; Pseudocapacitance behavior; Sodium; Sodium ion batteries; Storage batteries; Storage capacity; Structural stability; Ultralong-life; Vanadium; X ray powder diffraction; Ultralong-life; Sodium ion batteries; MIL-101(V); Pseudocapacitance behavior; Na3V2(PO4)3/carbon cathode composites; High-rate capability
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.03.346

Because of sodium abundance, sodium ion batteries attract a lot of attention for advanced energy storage applications. As the main member of cathodes, NASICON-type structured Na3V2(PO4)3 contributes excellent ion shuttling rate and structure stability. However, the low electrical conductivity (<10−4 S cm−1) of Na3V2(PO4)3 limits its application in high power field. Herein, the Na3V2(PO4)3 nanoparticles anchored in the carbon matrix are successfully prepared through using the V-based metal organic frameworks (MIL-101(V)). As expected, these small Na3V2(PO4)3 grains are uniformly distributed in Na3V2(PO4)3/carbon composite accompanying with the presence of 3D carbon framework. When used as cathode for sodium ion batteries, Na3V2(PO4)3/carbon composite delivers a considerable Na-storage capacity of 136.4 mAh g−1 at the current rate of 1 C and in the voltage range of 2.5–3.8 V. Even at the current rate of 5 C and 10 C, the 84.17% and 84.5% of capacity retentions are surprisingly kept after 1,000 cycles, verifying its ultra-long cycling life. Electrochemical impedance spectroscopy substantiates a decreased charge transfer resistance for Na3V2(PO4)3/carbon composite. Assisting with the detailed kinetic analysis, it is found that the enhanced surface-controlled behaviors mainly lead to the improvement of sodium-storage capability. The ex-situ scanning electron microscope and X-ray powder diffraction analysis demonstrates that unique architecture of as-prepared Na3V2(PO4)3/carbon composite significantly enhances structural stability during the fast cycling. This work provides insights on design of future advanced electrode materials for sodium ion batteries. [Display omitted] •M-NVP/C composite is synthesized using MIL-101(V) as both carbon and vanadium source.•NVP nanoparticles are surrounded by 3D carbon framework and conductive network structure.•M-NVP/C composite demonstrates high-rate capability and long-term cyclability.•Pseudocapacitive behavior of M-NVP/C composite is confirmed by kinetics analysis.•Ex-situ SEM and XRD analysis proves the good structure stability of M-NVP/C composite.