Bio-inspired adenine-benzoquinone-adenine pillar grafted graphene oxide materials with excellent cycle stability for high energy and power density supercapacitor applications

Abstract

To achieve outstanding electrochemical performance of designing low cost, robust electrodes based on graphene oxide (GO) and naturally abundant organic material remains challenging. However, fabrication of such electrode is mainly hindered by their choice and reactivity on GO surface. Although construction of such electrodes has been significantly advanced, developing supercapacitors (SCs) with higher electrical conductivity, power and energy density and cycling stability remain far from the reality. Inspired from the nature that uses benzoquinone (BQ) in photosystem for photosynthesis and adenine in deoxynucleic acid (DNA) serving for maintaining the life's genetic code functions. Here, we report fabrication of a facile three-dimensional electrode based on bioinspired ABQA covalently pillared GO surface. The resulting three-electrode supercapacitor devices delivered an enhanced specific capacitance (Csp) of 203.20 F/g at 5 mV/s in the potential window of −0.4 to 0.8 V. Moreover, as-assembled symmetric ABQA-GO/CP// ABQA-GO/CP exhibits Csp of 134 F/g at 0.5 A/g current density within the potential window of −0.2 to 1.2 V. Further, they display a high power density of 1256 W/kg and a high energy density of 32.87 Wh/kg (0.5 A/g). The two-electrode symmetric supercapacitor exhibited outstanding cycling stability with 106 % capacitance retention after 5000 charge /discharge cycles at discharge current of 5 A/g, suggesting their superior electrochemical performance when compared to that of conventional supercapacitors. These types of supercapacitors have a great promise for commercial applications and may even transform to become the state-of-art technology.