Effects of low doping on the improvement of cathode materials Na_3+xV_2−xM_x(PO₄)₃ (M = Co²⁺, Cu²⁺; x = 0.01–0.05) for SIBs

Abstract

In this work, we demonstrate the advantages of low doping in relation to the electrochemical properties of the NVP cathode for use in SIBs.

Activating the Extra Redox Couple of Co2+/Co3+ for a Synergistic K/Co Co-Substituted and Carbon Nanotube-Enwrapped Na3V2(PO4)3 Cathode with a Superior Sodium Storage Property

“…Significantly, the optimized KC0.05/CNTs obviously deliver a high and stable capacity at ultrahigh rates, suggesting that it possesses an enhanced structural stability and an efficient electronic conductive network. Besides, we also compare the comprehensive performance containing initial capacity, cyclic property, and retention ratio of KC0.05/CNTs with other modified NVP materials reported previously. , As shown in Figure h, it is clearly that KC0.05/CNTs exhibits a higher comprehensive performance. Above all, the greatly improved electrochemical performance demonstrates that the strategy of K/Co co-doping and CNTs enwrapping can strongly enhance the structural stability, expand channels for Na + migration, and establish a perfect conductive network to improve the sodium storage property of NVP system…”

“…Besides, we also compare the comprehensive performance containing initial capacity, cyclic property, and retention ratio of KC0.05/CNTs with other modified NVP materials reported previously. 49,50 As shown in Figure 4h, it is clearly that KC0.05/CNTs exhibits a higher comprehensive performance. Above all, the greatly improved electrochemical performance demonstrates that the strategy of K/Co co-doping and CNTs enwrapping can strongly enhance the structural expand channels for Na + migration, and establish a perfect conductive network to improve the sodium storage property of NVP system Figure 5a depicts the GCD curves of KC0.05/CNTs and NVP within the range in 2.3−4.1 V. The two electrodes both release a long plat at 3.4 V belonging to the V 3+ /V 4+ redox pair and the charge capacity of KC0.05/CNTs (119.4 mA h g −1 ) is greatly more than NVP (87.5 mA h g −1 ).…”

3D porous spheroidal Na4Mn0.9Ce0.1V(PO4)3@CeO2/C cathode for high-energy Na ion batteries

“…It was found that the Na 4 Mn 0.9 Ce 0.1 V(PO 4 ) 3 @CeO 2 /C electrode possessed more stable kinetic properties during the cycling test. 64…”

Constructing a multidimensional porous structure of K/Co co-substituted Na3V2(PO4)3/C attached on the lamellar Ti3C2Tx MXene substrate for superior sodium storage property

“…Notably, phosphate materials, which belong to the polyanion type with strong covalence bindings, have attracted plentiful attention due to their high safety and stability. Na 3 V 2 (PO 4 ) 3 (NVP), the representative phosphate material, has been widely applied as the cathode in SIBs; [25][26][27][28][29][30] it consists of repeated V 2 (PO 4 ) 3 groups, which further form an open 3D NASICON framework with lots of inner channels. Notably, it possesses excellent electrochemical properties with the theoretical potential and capacity values of 3.4 V and 117.6 mA h g −1 .…”

“…Na 3 V 2 (PO 4 ) 3 (NVP), the representative phosphate material, has been widely applied as the cathode in SIBs; 25–30 it consists of repeated V 2 (PO 4 ) 3 groups, which further form an open 3D NASICON framework with lots of inner channels. Notably, it possesses excellent electrochemical properties with the theoretical potential and capacity values of 3.4 V and 117.6 mA h g −1 .…”