Engineering a hierarchical carbon supported magnetite nanoparticles composite from metal organic framework and graphene oxide for lithium-ion storage.

Fe based metal organic framework (MOF) materials are being extensively investigated as a precursor sample for engineering carbon supported iron containing nanoparticles composites. Rational design and engineering Fe-containing MOFs with optimized structures using economic and eco-friendly methods is a challenging task. In this work, 1,3,5-benzenetricarboxylic acid (C9H6O6, trimesic acid, H3BTC) and metal Fe are employed to synthesize a MOF sample Fe-BTC in a mild hydrothermal condition. Moreover, with the addition of a small quantity of graphene oxide (GO) as dispersant, a redox coprecipitation reaction has taken place where small Fe-BTC domains well dispersed by reduced graphene oxide (RGO). The Fe-BTC/RGO intermediate sample is finally converted to the hierarchical Fe3O4@C/RGO composite, which delivers an ultrahigh specific capacity of 1262.61 mAh·g-1 at 200 mA·g-1 after 150 cycles and a superior reversible capacity of 910.65 mAh·g-1 at 1000 mA·g-1 after 300 cycles in half cells. The full cell performance for the Fe3O4@C/RGO composite have been studied. It is also revealed that the improved structural stability, high pseudocapacitive contribution and enhanced lithium-ion and electron transportation conditions jointly guarantee the outstanding lithium-ion storage performances for the Fe3O4@C/RGO composite over long-time cycling. The synthesized samples have good potential for wider application.