Design of highly porous Fe 3 O 4 @reduced graphene oxide via a facile PMAA-induced assembly

• Published in: RSC advances 2019-09, Vol.9 (48), p.27927-27936
• Main Authors: Wang, Huan, Kalubowilage, Madumali, Bossmann, Stefan H, Amama, Placidus B
• Format: Article
• Language: English
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c9ra04980k

Advances in the synthesis and processing of graphene-based materials have presented the opportunity to design novel lithium-ion battery (LIB) anode materials that can meet the power requirements of next-generation power devices. In this work, a poly(methacrylic acid) (PMAA)-induced self-assembly process was used to design super-mesoporous Fe O and reduced-graphene-oxide (Fe O @RGO) anode materials. We demonstrate the relationship between the media pH and Fe O @RGO nanostructure, in terms of dispersion state of PMAA-stabilized Fe O @GO sheets at different surrounding pH values, and porosity of the resulted Fe O @RGO anode. The anode shows a high surface area of 338.8 m g with a large amount of 10-40 nm mesopores, which facilitates the kinetics of Li-ions and electrons, and improves electrode durability. As a result, Fe O @RGO delivers high specific-charge capacities of 740 mA h g to 200 mA h g at various current densities of 0.5 A g to 10 A g , and an excellent capacity-retention capability even after long-term charge-discharge cycles. The PMAA-induced assembly method addresses the issue of poor dispersion of Fe O -coated graphene materials-which is a major impediment in the synthesis process-and provides a facile synthetic pathway for depositing Fe O and other metal oxide nanoparticles on highly porous RGO.