Hollow Bio-derived Polymer Nanospheres with Ordered Mesopores for Sodium-Ion Battery

Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex materials. However, the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as microstructure. Here, we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy, using phytic acid-based natural compounds as an example, for the spatially controlled fabrication of metal coordination bio-derived polymers. The resultant ferric phytate polymer nanospheres feature hollow architecture, ordered meso-channels of ~ 12 nm, high surface area of 401 m² g^-1, and large pore volume of 0.53 cm³ g^-1. As an advanced anode material, this bio-derivative polymer delivers a remarkable reversible capacity of 540 mAh g^-1 at 50 mA g^-1, good rate capability, and cycling stability for sodium-ion batteries. This study holds great potential of the design of new complex bio-materials with supramolecular chemistry.