Mo₂P₂O₁₁: A Potential Cathode Material for Rechargeable Sodium-Ion Batteries

Abstract

Due to the limiting lithium reserve and increasing price of lithium, alternatives to Li-ion batteries are growing rapidly. The world is now focusing on developing electrodes beyond Li-ion-based rechargeable batteries for portable electronics. Iron, nickel, and Co-based NASICON structured materials give stable capacity with reversible intercalation of almost one sodium in the host lattice. In the current work, we suggest a cathode material made of 3D framework-structured molybdenum polyanionic phosphate (Mo2P2O11) for a reversible sodium-ion battery. Mo2P2O11 was synthesized using the heat treatment of the MoO2HPO4·H2O precursor at 560 °C, having the morphology of stacked flakes. Characterization techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, and energy-dispersive X-ray were utilized for confirming the structure and morphology of the materials. For electrochemical performance, cyclic voltammetry, charge–discharge, and stability tests have been performed. Mo2P2O11 work through the active participation of the Mo6+/4+ redox couple with reversible intercalation of Na+ ions. The electrode exhibits reversible intercalation at 3.0 V versus Na and a steady capacity of ∼90 mA h/g, that is, ∼1.4 Na per formula unit, achieving a Coulombic efficiency of nearly 100%. The current finding opens up a new route for using transition-metal phosphates as efficient and stable charge storage cathode materials for sodium-ion batteries.

Research Progress of Photovoltaic Cooling Systems Based on Phase Change Materials: An Overview

“…The average output power of the CPV-PCM-TE hybrid system increases by 23.52% compared with the CPV-TE coupling system. [198] Simulation The 3D numerical simulation has experimented under regular conditions. Heat flow is investigated from each layer of the PV/T system.…”

Recent Advances in Sodium-Ion Batteries: Cathode Materials

“…Deng et al fabricated a high-Nacontent Na7V3(P2O7)4, which was also used as a high-voltage SIB cathode at an average voltage of approximately 4.0 V with a capacity of approximately 80 mAh g −1 . Kumar et al proposed the use of Mo2P2O11 as a SIB cathode with a high capacity of approximately 90 mAh g −1 [143]. The structure of Mo2P2O11 is also a framework of MoO6 sites with PO4 and P2O7 sites.…”

Combustion-Synthesized KNiPO4: A Non-toxic, Robust, Intercalating Battery-Type Pseudocapacitive Electrode for Hybrid Supercapacitors as a Large-Scale Energy Storage Solution

“…3 3 Ni 0 . 6 7 PO 4 •H 2 O, 4 6 LiCoPO, 4 7 LiMnPO 4 , 4 8 NH 4 NiPO 4 •H 2 O, 49 NaVOPO 4 , 50 and Mo 2 P 2 O 11 , 51 for energy storage and delivery applications. However, a detailed investigation of their charge storage mechanism and electrochemical performances is yet to be established.…”

“…A strong X–O bond of the tetrahedron introduces ionicity in the M–O bond in the framework structure and decreases the covalent character of the M–O bond by increasing the distance between the antibonding orbitals and making the material suitable for high-voltage operation. Also, the introduction of the X–O bond increases the oxygen stability in the lattice, which makes polyanionic-type electrode materials safer for the high rate charge storage and delivery applications. − Transition-metal-phosphate-based materials have been widely studied, such as Ni 3 (PO 4 ) 2 , , Co 3 (PO 4 ) 2 , , γ-KCoPO 4 , KFePO 4 , NaFe 2 (SO 4 ) 2 PO 4 , CoNiP 2 O 7 , Na 3 Cr 2 (PO 4 ) 3 , Na 3 V 2 (PO 4 ) 3 , NaNiPO 4 , LiNiPO 4 , MP-VOPO 4 , NaTi 2 (PO 4 ) 3 , Ni 2 P 2 O 7 /Co 2 P 2 O 7 Na 3 Fe 2 (SO 4 ) 2 PO 4 , KCoO .33 Ni 0.67 PO 4 ·H 2 O, LiCoPO, LiMnPO 4 , NH 4 NiPO 4 ·H 2 O, NaVOPO 4 , and Mo 2 P 2 O 11 , for energy storage and delivery applications. However, a detailed investigation of their charge storage mechanism and electrochemical performances is yet to be established.…”