Design and fabrication of high performance supercapacitor with cellulosic paper electrode and plant-derived redox active molecules.

• Post-treatment process was developed to improve the capacitance of cellulose fibers. • Redox active ARS was firstly performed as post-treatment agent for PEDOT/CFs. • Cellulosic paper electrode showed capacitance as high as 2076 m F/cm2 at 0.5 mA/cm2. • Device with high energy density was achieved due to addition of redox electrolyte. As a promising substrate, cellulose fibers were widely investigated in supercapacitors for their low cost and sustainability. However, the low performance created great barrier for the future applications of the cellulosic paper-based supercapacitors. The performance of paper-based supercapaciors may be improved by the addition of redox active molecule. As a plant derived redox active molecule, Alizarin red S was used to improve the performance of PEDOT paper-based electrode via a simple post-treatment process. By combination of the treated paper electrode and the redox electrolyte, a symmetric paper-based supercapacitor with a superior performance of 2191.3 m F/cm2 (at 5 mA/cm2) and 4.87 mW h/cm3 (at power density of 36 mW/cm3) were fabricated. The charge and mass transfer mechanisms of paper electrode were detailed discussed. The simple and efficient strategy developed in this work opens up new doors for the development of other cellulose related high performance energy storage devices. [ABSTRACT FROM AUTHOR]