Understanding acid pretreatment of lotus leaves to prepare hard carbons as anodes for sodium ion batteries

The Anode Materials for Lithium‐Ion and Sodium‐Ion Batteries Based on Conversion Reactions: a Review

“…With the paucity of lithium metal and rising costs, as an alternative to LiBs, sodium-ion batteries (SiBs) are showing potential. [96,97] However, compared to the Li + ionic size (0.76 Å), the Na + ionic size (1.02 Å) is much larger and Na has a higher atomic weight (Li: 6, Na: 23), [98][99][100][101] which is somewhat restricted SiBs's rate capacity and energy density but still has significant application potential.…”

Sustainable Free‐Standing Electrode from Biomass Waste for Sodium‐Ion Batteries

“…[20] It is reported that the use of biomass waste can significantly reduce CO 2 and pollutants, and therefore this can act as an ideal resource for precursor NIB anodes. [18,21] Biomass precursors, such as banana peels, [22] pitch and lignin, [23,24] sucrose, [25] mangosteen shell, [26] lotus leaves, [27] exhibited excellent electrochemical performance in NIBs with economic and environmental benefits. An alternative biomass precursor could also be waste textiles such as silk fabrics, which have attracted interest owing to their unique mechanical properties and functionality.…”

Ultrathin Artificial Solid Electrolyte Interface Layer-Coated Biomass-Derived Hard Carbon as an Anode for Sodium-Ion Batteries

“…Hence, these materials are considered as potential anodes of SIBs. 4,5 Many strategies have been used to prepare various hard carbon materials by direct chemical synthesis 6−8 and carbonization of polymers or biomass for energy storage applications. 9−12 Among them, hard carbons derived from biomass are the most promising candidate for anodes of SIBs because of their sustainability, resource abundance, and simple fabrication process.…”

“…Graphite is widely used as an anode material for LIBs but provides an extremely low capacity for SIBs (∼30 mAh g –1 ). , This is due to the mismatch of the interlayer distance of graphite and the size of sodium ions and thermodynamic instability of the sodium graphite intercalation compound. , Hard carbon materials with an expanded interlayer distance between two graphene layers exhibit a high capacity (∼250 mAh g –1 ) and low operation potential (0.2 V vs Na/Na + ). Hence, these materials are considered as potential anodes of SIBs. , Many strategies have been used to prepare various hard carbon materials by direct chemical synthesis − and carbonization of polymers or biomass for energy storage applications. − Among them, hard carbons derived from biomass are the most promising candidate for anodes of SIBs because of their sustainability, resource abundance, and simple fabrication process. ,, Furthermore, the biomass precursors of the hard carbon always possess special microstructures, which have many advantages for electrochemical performances even after carbonization at high temperatures. , Nevertheless, the hard carbons have several issues for practical applications, such as low initial coulombic efficiency (ICE), high irreversible capacity loss, and low rate performances. − These drawbacks have been widely investigated by many studies. − The poor electrochemical performances arise from the turbostratic graphite-like structures with a defect-rich surface. The microstructure features cause a high contact surface area with an electrolyte that facilitates uneven and continuous growth of the solid electrolyte interphase (SEI) layer during the charge–discharge cycles .…”

“…The SEI layer would then inhibit sodium-ion and electron migration. Several studies have reported to tailor the microstructures and reduce the surface area by pretreatment and process optimization, ,, incorporating heteroatoms within the carbon lattice, − and hybrid composite design. , The methods mentioned above require complicated synthesis steps, high-temperature treatments, and precision process control limiting practical applications.…”