Advanced anode materials for sodium ion batteries: carbodiimides

Abstract

TMNCN (where TM = Mn2+ , Fe 2+ , Co 2+ or Ni 2+ ) have been recently proposed as electrochemically active materials for Na-ion insertion that operate via conversion reaction. Their electrochemical performance for Na-ion batteries is presented here with an emphasis on long-term cycling. With a very low voltage for Na insertion of ∼0.1V vs Na + /Na for MnNCN, the overpotential observed in batteries of MnNCN plays a very important role in their performance, evidencing big differences in the electrochemical performance between materials produced with different nano-and micrometer particle sizes evidenced by SEM images. A more suitable voltage for the conversion reaction accompanied by less overpotential is shown by FeNCN, CoNCN and NiNCN. Despite the lower reversible capacity achieved by FeNCN (450 mAh/g) in comparison with CoNCN and NiNCN in the first cycle; the smallest first-cycle irreversible capacity (220 mAh/g) and the lower voltage plateau (0.3 V vs Na + /Na) make FeNCN a good candidate as an anode material for sodium ion batteries. The voltages of conversion reaction are correlated with the calculated enthalpies of formation suggesting that thermodynamics dominates the observed electrochemical conversion reaction.

Synthesis and Characterisation of the Nitridocuprate(I) Nitride Carbodiimide (Sr6N)[CuN2][CN2]2

“…For M = Hg two modifications, one cyanamide and one carbodiimide, are known , . Interestingly, some of these compounds show potential applications as negative electrode materials for lithium and sodium ion batteries, corrosion protective layers, photovoltaic devices, fluorescent light sources, and light‐emitting diodes , . Due to the carbodiimide anion being a pseudo‐chalcogenide anion, it can act as a bridging ligand to allow effective magnetic super exchange between bridged paramagnetic cations, as seen for Cr 2 [CN 2 ] 3 and M [CN 2 ] ( M = Mn – Cu), which are isostructural to their respective oxide variants, exhibit similar magnetic ordering and also have the same colours .…”

“…For M = Hg two modifications, one cyanamide and one carbodiimide, are known. [13,14] Interestingly, some of these compounds show potential applications as negative electrode materials for lithium and sodium ion batteries, [15][16][17][18][19] corrosion protective layers, [20] photovoltaic devices, [21] fluorescent light sources [22,23] and light-emitting diodes. [24,25] Due to the carbodiimide anion being a pseudo-chalcogenide anion, it can act as a bridging ligand to allow effective magnetic super exchange between fraction and the identity of the [CN 2 ] 2anion as carbodiimide was confirmed by Raman spectroscopy.…”

Carbon-Interlayer SnO2–Sb2O3 Composite Core–Shell Structure Anodes for Sodium-Ion Batteries

“…The energy storage systems, especially for Li-ion batteries (LIBs), are increasingly important in commercial 3C (computer, communication, and consumer electronic) products, and new standards have been defined in the fields of electric/hybrid vehicles and industries with storage energy (Tarascon and Armand, 2001). As alternatives to LIBs, many attentions have been paid on the new energy storage devices (Shan et al, 2019), especially for sodium-ion batteries (SIBs), because of their similar potential closed to Li + and lower cost (Eguia-Barrio et al, 2017). The demand of stable electrode materials with low cost was mainly focused on various compounds, such as Na 3 V 2 (PO 4 ) 3 , Na 1.25 V 3 O 8 , and NaCrO 2 for cathode materials (Kim et al, 2012).…”

Reversible High Capacity and Reaction Mechanism of Cr2(NCN)3 Negative Electrodes for Li‐Ion Batteries

“…In 2016, our group reported the excellent performance of FeNCN with, for example, an impressive rate capability up to 30 C and stable capacity for more than 100 cycles . This article was followed by other reports exploring the reaction mechanism of transition and main‐group metal carbodiimides versus Li and Na ions . Similarly to most transition‐metal based anode materials, these materials are expected to react electrochemically with lithium through a conversion reaction but the reaction pathways or mechanisms of these carbodiimides, especially the trivalent ones, are not yet completely clarified.…”

“…exploring the reaction mechanism of transition and main-group metal carbodiimides versus Li and Na ions. [28][29][30][31][32] Similarly to most transition-metal based anode materials, these materials are expected to react electrochemically with lithium through a conversion reaction but the reaction pathways or mechanisms of these carbodiimides, especially the trivalent ones, are not yet completely clarified.…”