Spherical mesocrystals from self-assembly of folic acid and nickel(II) ion for high-performance supercapacitors

Abstract

The formation of spherical mesocrystalline microparticles (FA-Ni) was achieved through the self-assembly between folic acid and nickel ions. Such favorable structure and the existence of abundant active sites within FA-Ni were responsible for the high specific capacitance (912 F g−1 at 0.5 A g−1) and energy density (27.81 Wh kg−1) of the material when used as a supercapacitor. Meanwhile, the as-synthesized FA-Ni showed excellent stability (97.6% capacitance retention over 8000 cycles at 10 A g−1). This facile method would be expected to benefit for the preparation of mesocrystals based on biological ligands and their use as the promising electrode materials for high performance supercapacitors.