A fabrication strategy for porous carbon spheres based on cross-linked chitosan/poly(γ-glutamic acid) colloidal particles

A new strategy was developed to prepare nanoscale porous carbon spheres (PCSs) using cross-linked chitosan/poly(γ-glutamic acid) colloidal particles as precursor. The fabricated cross-linked chitosan/poly(γ-glutamic acid) colloidal particles (Ca 2+ /CS/γ-PGA CPs) were prepared from the self-assembly of negatively charged poly(γ-glutamic acid) and positively charged chitosan, and the cross-linking of Ca 2+ in aqueous solution, via the electrostatic interaction. After lyophilization, the Ca 2+ /CS/γ-PGA CPs power was obtained, followed by carbonization in a tube furnace under N 2 atmosphere. Finally, the products were washed by hydrochloric acid, obtaining PCSs with hierarchical pore structure and super-hydrophobicity. The prepared PCSs exhibited excellent separation performance for oil-in-water emulsions.