Prussian Blue Anchored on Reduced Graphene Oxide Substrate Achieving High Voltage in Symmetric Supercapacitor
Lindiomar Borges de Avila, Pablo A. Serrano, Luis T. Quispe, Adriana Dantas, Diogo Pontes Costa, Edy E. Cuevas-Arizaca, Diana Patricia Paredes Chávez, César Daniel Valdivia Portugal, Christian Klaus Müller
Abstract
In this work, iron hexacyanoferrate (FeHCF—Prussian blue) particles have been grown onto a reduced graphene oxide substrate through a pulsed electrodeposition process. Thus, the prepared FeHCF electrode exhibits a specific volumetric capacitance of 88 F cm−3 (specific areal capacitance of 26.6 mF cm−2) and high cycling stability with a capacitance retention of 93.7% over 10,000 galvanostatic charge–discharge cycles in a 1 M KCl electrolyte. Furthermore, two identical FeHCF electrodes were paired up in order to construct a symmetrical supercapacitor, which delivers a wide potential window of 2 V in a 1 M KCl electrolyte and demonstrates a large energy density of 27.5 mWh cm−3 at a high power density of 330 W cm−3.