# Light-Induced Enhancement of Cross-Linked Viologen-Fluorene Polymer Electrode for High-Performance Supercapacitors

## TL;DR

This paper introduces a light-responsive polymer electrode that significantly boosts the performance of supercapacitors when exposed to visible light.

## Contribution

A new photoactive polymer electrode is developed using a thiol–ene click reaction for enhanced supercapacitor performance under light.

## Key findings

- The electrode's specific capacitance doubled under visible light, reaching 304.1 F/g.
- The energy density increased from 35 to 60 Wh/kg when illuminated.
- The electrode showed long-term stability over 10,000 cycles.

## Abstract

Porous organic polymers (POPs) are generally prepared
as insoluble
powders and coated onto the electrode surface with another polymer
binders such as PVDF: HFP during electrode preparation. POP-based
electrodes formed through surface cross-linking hold promise for supercapacitor
applications. In this study, a new pyridinium-fluorene donor–acceptor
monomer (FBP_allyl) was synthesized and cross-linked onto graphene
sheet conductive substrates via a thiol–ene click reaction
to prepare a photoactive polymer electrode with light-harvesting and
charge storage capability. The specific capacitance of the fabricated
electrodes at 2.0 A/g was almost doubled under visible light, from
152.7 F/g (dark) to 304.1 F/g (light). In a three-electrode configuration,
the electrochemical cell exhibited a power density of over 3000 W/kg,
while the energy density increased from 35 to 60 Wh/kg under illumination.
Furthermore, the prepared electrode cell showed long-term stability
over 10,000 cycles, demonstrating that combining donor–acceptor
engineering with thiol–ene cross-coupling is an effective approach
for developing photoassisted capacitors with improved electrochemical
performance.