Rational Design for Crosslinked and Pried-Open Redox-Active Graphene Electrode Materials and High-Performance...

Developing high-performance graphene-based electrode materials through rational structural design remains a critical challenge for advanced supercapacitors. In this work, a unique molecule (DAPTO) featuring four carbonyl groups and a conjugated backbone was screened and successfully introduced into reduced graphene oxide (rGO) sheets via a one-step hydrothermal process. This strategy effectively suppresses the restacking of rGO while simultaneously providing abundant pseudocapacitive active sites. Structural and morphological characterizations confirm the successful grafting of DAPTO and the formation of a stable layered architecture with enlarged interlayer spacing. By optimizing the reaction mass ratio, the optimal sample, DAPTO-rGO-1, was identified, delivering a high specific capacitance of 680 F g^-1 in a three-electrode system, along with excellent rate capability and low charge-transfer resistance. Furthermore, a flexible symmetric supercapacitor assembled using a PVA/H₂SO₄ gel electrolyte exhibits a high specific capacitance of 295 F g^-1 and outstanding rate performance. The device also achieves a high energy density of 26.2 Wh kg^-1 at a power density of 800 W kg^-1. This work provides valuable insights into the design of advanced graphene-based electrodes.