Enhanced electrochemical supercapacitors from metal silicates (Zn, Mn, Ni and Co) by multi-step treatment of natural green algae†
Abstract
Metal silicates (Zn, Mn, Ni and Co) were synthesized from natural green algae (GAs) as supercapacitor electrodes. In this study, a multi-step treatment with two kinds of porogens was used to produce a larger specific surface area and more abundant hierarchical pores. Firstly, GAs were treated with 1.0 M NaCl solution to prepare large pores. Secondly, metal silicates were synthesized from GAs using a hydrothermal reaction. Lastly, the as-synthesized samples were soaked in 3.0 M NaOH solution to obtain the products (m-C-MSi, M = Zn, Mn, Ni and Co). Compared with the composites without multi-step treatment, the synthetic materials in this research possess excellent electrochemical properties both as electrodes and as HSCs. This work proved that the multi-step treatment with porogens is an effective method to enhance the electrochemical performance of metal-silicate supercapacitors.