Chemically Binding Vanadium Sulfide in Carbon Carriers to Boost Reaction Kinetics for Potassium Storage

Abstract

Potassium-ion batteries (PIBs) have received widespread interest on account of low redox potential, low price, and high abundance of potassium. However, attributing to the large radius of K+ ions, the structure of electrode material is easily damaged during the potassiation/depotassiation process. Herein, the unique chemical bonding of encapsulating V5.45S8 nanoparticles in N,S codoped multichannel carbon nanofibers (CB-VS@NSCNFs) is designed through electrospinning and in situ vulcanization techniques. The anchoring effect (V–C chemical bonding) of the V5.45S8 nanoparticles with carbon carriers assists in shortening the K+/e– transport path and alleviating the structural changes, which is highlighted to acquire a stable cycle lifespan. Also, codoped multichannel carbon nanofibers provide abundant active sites for pseudocapacitive behavior to achieve fast kinetics. As a synergistic result, when CB-VS@NSCNFs are evaluated as anode material for PIBs, they exhibit a high reversible capacity of 411 mA h g–1 at 0.1 A g–1, decent rate property with a capacity of up to 123 mA h g–1 at 6 A g–1, and good cycling stability of 500 cycles at 1 A g–1.

Formation of Mn–Ni Prussian Blue Analogue Spheres as a Superior Cathode Material for Potassium-Ion Batteries

“…However, the rarity of lithium resources inevitably limits its large-scale application . Compared with LIBs, potassium-ion batteries (PIBs) have attracted extensive attention from researchers recently on account of their low cost and wide distribution. − The most significant merit of PIBs is the negative potential of K/K + (−2.93 V vs standard hydrogen electrode (SHE)), lower than that of Na/Na + (−2.71 V vs SHE). , Moreover, graphitic carbon (a widely used anode material in LIBs) can be employed in PIBs but cannot be used in sodium-ion batteries (SIBs) . Therefore, though it is difficult to find electrode materials for large K + , a series of materials have been designed for PIBs. − …”

Vanadium fluorophosphates: advanced cathode materials for next-generation secondary batteries

“…Besides, they exhibit inferior cycling stability due to the serious volume dilatation or even structural sabotage after irreversible Na + /K + (de)insertion. [33][34][35][36][37] Thus, the development of advanced cathodes with high energy performance and great cyclability becomes a great challenge to achieve high-performance SIBs/ PIBs, which is significant to realize their practical applications.…”