High-Performance Flexible Symmetric Supercapacitor Device Based on Nitroaniline-Functionalized Benzoquinone

A simple approach to design the molecular architecture based on modified benzoquinone and its flexible supercapacitor device is demonstrated. In present work, two electron-withdrawing subunits such as 2-nitroaniline ( NA ) and 3,5-dinitro aniline ( DNA ) are utilized to functionalize benzoquinone ( BQ ) core. As-prepared electrode materials based on BQ-NA and BQ-DNA on graphite foil ( GF ) are directly employed to fabricate a three-electrode supercapacitor (SC) device in 1 M H 2 SO 4 electrolyte. At 0.5 A g –1 current density, the BQ-DNA/GF electrode-based SC can deliver higher specific capacitance ( C sp ) of 341.13 F g –1 compared to the BQ-NA/GF SC device 322.47 F g –1 . This could be ascribed to the higher electron-withdrawing effect of the four –NO 2 groups in BQ-DNA . Moreover, two-electrode BQ-DNA/GF//BQ-DNA/GF symmetric SC device and flexible symmetric supercapacitor (SSC) device were created using the GF surface. The BQ-DNA/GF -based FSSC device at a 0° bending angle exhibits noticeable C sp with 81.66% C sp retention after 5000 cycles at 1 mA cm –2 current density. The highest energy density of 12.81 μW h cm –2 at 1.36 mW cm –2 power density was achieved for FSSC. The FSSC cell configuration at 180° bending angle also retains excellent C sp . The present work provides a way to design high-performance energy storage materials based on organic compounds for flexible electronics and wearable device architectures.