The synthesis and electrochemical properties of low-crystallinity iron silicate derived from reed leaves as a supercapacitor electrode material

The design and preparation of electrode materials with excellent performance is particularly important due to the current global scarcity of energy supplies, especially those using sustainable and renewable materials. In this work, it is first proposed to apply iron silicate (FeSi), which is synthesized using environmentally friendly biomass as a raw material, as an electrode material for supercapacitors (SCs). FeSi is derived from the calcination of reed leaves (RLs) in combination with a hydrothermal method, and spherical FeSi retains the porosity of the RL precursors and shows remarkable electrochemical performance. The specific capacitance of FeSi as a SC electrode can reach 575 F g-1 at 0.5 A g-1 in the voltage window from -1 to -0.5 V. Simultaneously, the FeSi electrode exhibits favorable cycling stability with 76% capacitance retention after 10 000 cycles and outstanding electrical conductivity. This finding provides a novel method of preparing a kind of untapped electrode material, porous FeSi nanoparticles derived from RLs, and the resulting FeSi material shows enormous potential for energy storage via high-performance SCs.