One-pot synthesis of FeF3/graphene composite for sodium secondary batteries

Promising Dual-Doped Graphene Aerogel/SnS2 Nanocrystal Building High Performance Sodium Ion Batteries

“…Sustainable sodium ion batteries (SIBs) have attracted much attention in renewable energy and smart grid applications because of high sodium reserves and significantly lower cost as well as the insertion chemistry resembling lithium ion batteries (LIBs). − It has been accepted that the Na ion intercalation into electrode materials is similar to that of Li ions. However, the radius of Na + (1.06 Å) is about 1.4 times larger than that of Li + (0.76 Å). , As a result, SIBs face significant challenges of anisotropic volume expansion, resulting in active material pulverization and insufficient contact with the current collector or conductive agent . Additionally, from the energy density perspective, a considerable drawback is that the redox potential of Na is higher than that of Li.…”

“…However, the radius of Na + (1.06 Å) is about 1.4 times larger than that of Li + (0.76 Å). 4,5 As a result, SIBs face significant challenges of anisotropic volume expansion, resulting in active material pulverization and insufficient contact with the current collector or conductive agent. 6 Additionally, from the energy density perspective, a considerable drawback is that the redox potential of Na is higher than that of Li.…”

Fluorinated Materials as Positive Electrodes for Li- and Na-Ion Batteries

“…The first tests in NIB configuration were performed in 2009 for several MF 3 fluorides (M = Ti, Mn, Fe, Co); only iron trifluoride maintained a significant capacity close to 100 mAh g –1 (4.0–1.5 V) . In this same NIB configuration, Bao et al proposed composite FeF 3 -graphene nanoparticles obtained by mechanical grinding with an initial capacity of 206 mAh g –1 decreasing during cycling (100 mAh g –1 , 50 cycles, 4.5–1.5 V) . It must be noted that a LiF/FeF 2 mixture, obtained by the sol–gel route, led to FeF 3 during the first charge …”

“…204 In this same NIB configuration, Bao et al proposed composite FeF 3 -graphene nanoparticles obtained by mechanical grinding with an initial capacity of 206 mAh g −1 decreasing during cycling (100 mAh g −1 , 50 cycles, 4.5−1.5 V). 206 It must be noted that a LiF/FeF 2 mixture, obtained by the sol−gel route, led to FeF 3 during the first charge. 207 FeF 3 is stable in the presence of the electrolyte LiPF 6 up to 300 °C; this temperature rises to 500 °C by replacing the mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) with methyl difluoroacetate (MFA) without impact on the electrochemical performance.…”

Amorphous FeF3/C nanocomposite cathode derived from metal–organic frameworks for sodium ion batteries

“…In order to overcome these problems of FeF 3 , different types of carbonaceous materials, 16 such as graphite, 17 acetylene black, 18,19 reduced graphene oxide, 20 carbon nanotube, 21,22 and graphene, [23][24][25][26] have been used to obtain composites with FeF 3 nanostructures, which can accelerate the reaction kinetics due to shortened electron and iron diffusion distances, and relieve pulverizations due to volume expansion. 32 This implies that uoride amorphization, along with defect generation or strain relief is of importance for improving the ion storage performance, 32 which may result from a new structure being reconstructed from the amorphous structure during the charge/discharge process, with this new structure being more in favor of ion diffusion in the electrode materials.…”