Improved Reversibility of Fe³⁺/Fe⁴⁺ Redox Couple in Sodium Super Ion Conductor Type Na₃Fe₂(PO₄)₃ for Sodium‐Ion Batteries

Abstract

The methodology employed here utilizes the sodium super ion conductor type sodium iron phosphate wrapped with conducting carbon network to generate a stable Fe /Fe redox couple, thereby exhibiting higher operating voltage and energy density of sodium-ion batteries. This new class of sodium iron phosphate wrapped by carbon also displays a cycling stability with >96% capacity retention after 200 cycles.

Sodium‐Ion Batteries: From Academic Research to Practical Commercialization

“…These cathode materials include layer-structured transition metal oxides, [4][5][6] polyanionic-type compounds, [7,8] Prussian blue analogues, [9,10] and organic-based materials. [11,12] Meanwhile, significant progress has also been made on anode materials for SIBs, and various materials have been explored as promising candidates, including carbonaceous materials, [13][14][15] metals or alloys, [16][17][18][19][20] phosphorus, [21,22] phosphide, [23,24] oxides, [25,26] sulfides, [27,28] and phosphates.…”

Lone‐Pair Enhanced Birefringence in an Alkaline‐Earth Metal Tin(II) Phosphate BaSn2(PO4)2

“…The inorganic metal phosphates are intensively researched for their potential application in catalysis, ion exchange, luminescence, optical materials and so on . In particular, they can serve as important photoelectric functional materials for laser frequency conversion.…”

“…This compound is expected to have al arge birefringence with Dn % 0.071 at 1064 nm, owing to the presence of stereochemically active lone pair metal cations.The inorganic metal phosphates are intensively researched for their potential applicationi nc atalysis, ion exchange, luminescence, optical materials and so on. [1][2][3][4][5][6][7] In particular,t hey can serve as important photoelectric functional materials for laser frequency conversion. For example, KH 2 PO 4 (KDP), [8][9] and KTiOPO 4 (KTP), [10][11] are among the commercial nonlinear optical (NLO) crystalsapplied in the near infrared, visible, and ultraviolet spectralr egions.…”

Single‐phase All‐solid‐state Silver Battery using Ag1.5Cr0.5Ti1.5(PO4)3 as Anode, Cathode, and Electrolyte

“…demonstrated a proof‐of‐concept for a single‐material battery using Li 10 GeP 2 S 12 as the electrolyte, anode, and cathode to eliminate interfacial resistance between the electrodes and electrolyte . The NASICON (Na Super Ionic CONductor)‐type materials are well‐known as promising candidates for electrolyte and electrode . We have recently reported NASICON‐type single‐phase all‐solid‐state batteries that are made from a single material using Na 3 V 2‐x Zr x (PO 4 ) 3 , Li 3 V 2‐x Al x (PO 4 ) 3 , and Li 1.5 Cr 0.5 Ti 1.5 (PO 4 ) 3 .…”