Synthesis and characterization of novel hierarchical metal oxide using scallion root as biotemplate

The roots of plants have rarely been used as templates. In this work, four novel hierarchical metal oxides were firstly synthesized by a simple immersion and calcination method using scallion root as natural biotemplate. The as-synthesized metal oxides have principally inherited the tubular frame structure of scallion root with rib-shaped inside walls. The hierarchical tubular structure of Co3O4, Fe2O3 and NiO are assembled by small particles with diameter of 7-20 nm, while the morphology of the building blocks for ZnO micro-tubes changes from hexagonal nanoplates to hexagonal nanorods with the increasing concentration of the Zn2+ immersing solution. These results reveal that scallion root is a good biotemplate for the synthesis of novel hierarchical metal oxides. (C) 2018 Elsevier B.V. All rights reserved.