Microalgae-Templated Spray Drying for Hierarchical and Porous Fe3O4/C Composite Microspheres as Li-ion Battery Anode Materials

Abstract

A method of microalgae-templated spray drying to develop hierarchical porous Fe3O4/C composite microspheres as anode materials for Li-ion batteries was developed. During the spray-drying process, individual microalgae serve as building blocks of raspberry-like hollow microspheres via self-assembly. In the present study, microalgae-derived carbon matrices, naturally doped heteroatoms, and hierarchical porous structural features synergistically contributed to the high electrochemical performance of the Fe3O4/C composite microspheres, enabling a discharge capacity of 1375 mA·h·g−1 after 700 cycles at a current density of 1 A/g. Notably, the microalgal frameworks of the Fe3O4/C composite microspheres were maintained over the course of charge/discharge cycling, thus demonstrating the structural stability of the composite microspheres against pulverization. In contrast, the sample fabricated without microalgal templating showed significant capacity drops (up to ~40% of initial capacity) during the early cycles. Clearly, templating of microalgae endows anode materials with superior cycling stability.

Carbon Double Coated Fe3O4@C@C Nanoparticles: Morphology Features, Magnetic Properties, Dye Adsorption

“…It provides exceptional chemical stability and protects the magnetic core from oxidation, allowing further functionalization of the carbon surface. Core-shell nanostructures consisting of the iron oxide magnetic core coated with non-magnetic carbon demonstrate unique properties and technological capabilities [ 1 , 2 , 3 , 4 , 5 , 6 ].…”

“…Several authors considered Fe 3 O 4 @C nanostructures as the basis for anode materials of lithium-ion batteries [ 2 , 3 , 4 ]. The hierarchical Fe 3 O 4 @C microspheres obtained by the self-assembling of microalgae were shown in [ 2 ] to be excellent as anode materials for lithium-ion batteries.…”

“…Several authors considered Fe 3 O 4 @C nanostructures as the basis for anode materials of lithium-ion batteries [ 2 , 3 , 4 ]. The hierarchical Fe 3 O 4 @C microspheres obtained by the self-assembling of microalgae were shown in [ 2 ] to be excellent as anode materials for lithium-ion batteries. Fe 3 O 4 nanoparticles mechanically mixed with carbon fibers were used in a solid-state battery with a sulfide electrolyte; they were characterized by high capacitance along with very good recovery [ 3 ].…”