Enhanced Energy Storage of Fe<sub>3</sub>O<sub>4</sub> Nanoparticles Embedded in N‐Doped Graphene
Susana Chauque, Adriano H. Braga, Renato V. Gonçalves, Liane M. Rossi, Roberto M. Torresi
Abstract
Abstract We report the synthesis and application of a material composed of Fe 3 O 4 nanoparticles embedded in N‐doped graphene sheets (Fe 3 O 4 @N‐doped graphene) as a negative electrode for Li batteries. We study the influence of N‐doped graphene on the storage capacity of Fe 3 O 4 using different electrochemical techniques. The as‐prepared Fe 3 O 4 materials presented high‐quality crystalline nanostructures. The N‐doped graphene sheets improve the conductivity between the Fe 3 O 4 nanoparticles, allowing a faster charge transfer process than that for pure magnetite, as well as the presence of porous particles in the hybrid composite. The Fe 3 O 4 @N‐doped graphene material show the best Li storage capacity maintaining specific capacity values of 910 mA h g −1 during 150 cycles performed at 0.05 A g −1 and 850 mA h g −1 at 0.1 A g −1 during the following 50 cycles. The N‐doped graphene sheets resist the volume changes that occur during cycling processes in rate capability experiments. We provide a simple and novel method to obtain a material with a higher superficial area and conductivity between particles, allowing great performance as a negative electrode for Li batteries application.