Graphene modification with chrysin molecules as a high performance electrode material for supercapacitor

In this study, chrysin (CHY) molecules are immobilized on the surfaces of graphene oxide (GO) via & pi;-& pi; in-teractions to obtain organic molecular-modified reduced graphene oxide (RGO) composite electrode material (CHY/RGO) by one-step hydrothermal. On one hand, CHY molecules can contribute to capacitance through faradic reactions. On the other hand, they act as spacers that impede the accumulation of graphene nanosheets and promote electrolyte ion migration. As a result, CHY/RGO exhibits excellent capacitance performance. The specific capacitance is up to 707F g-1 (1 A g-1), and the capacitance remains 100% after 10 000 circles. In addition, the symmetrical supercapacitor (CHY/RGO//CHY/RGO) displays excellent energy storage perfor-mance, achieving an energy density of 38 Wh kg-1 at a power density of 800 W kg-1. Two CHY/RGO//CHY/ RGO devices in series is capable of lighting 50 LEDs. Density functional theory (DFT) calculations show that CHY molecules are adsorbed parallel to the RGO by the & pi;-& pi; stacking. The DFT calculations also indicate that the modification of CHY molecules alters the charge distribution on the surface of RGO. Therefore, CHY/RGO composites offer a higher capacitance and superior cycle stability, making them a promising choice for future energy storage electrode materials.

Automated summary

In this study, chrysin (CHY) molecules were immobilized on graphene oxide (GO) surfaces via π-π interactions to obtain organic molecular-modified reduced graphene oxide (RGO) composite electrode material (CHY/RGO). The CHY molecules contribute to capacitance through faradic reactions and act as spacers to prevent graphene nanosheet accumulation, facilitating electrolyte ion migration. As a result, CHY/RGO exhibits excellent capacitance performance with a specific capacitance of 707F g-1 (1 A g-1) and 100% capacitance retention after 10,000 cycles. Furthermore, a symmetrical supercapacitor (CHY/RGO//CHY/RGO) demonstrates impressive energy storage performance, achieving an energy density of 38 Wh kg-1 at a power density of 800 W kg-1 and capable of lighting 50 LEDs when two devices are connected in series. Density functional theory (DFT) calculations reveal that CHY molecules are adsorbed parallel to RGO through π-π stacking and alter the charge distribution on RGO surfaces. Consequently, CHY/RGO composites offer higher capacitance and superior cycle stability, making them a promising choice for future energy storage electrode materials.