Engineering PSS-b-PAPEG (Poly(styrenesulfonate)-block-Poly(Allyloxy Polyethylene Glycol)) Block Copolymers for Bicontinuous PEDOT (Poly(3,4-Ethylenedioxythiophene)):PSS Networks: Unlocking Maximum Capacitance via Optimal Block Ratio Tuning

This work demonstrates a molecular engineering strategy to optimize the capacitive performance of PEDOT:PSS by precisely controlling the structure of the amphiphilic block copolymer PSS-b-PAPEG (poly(styrenesulfonate)-block-poly(allyloxy polyethylene glycol)). Five copolymers with PSS:PAPEG ratios of 2:1, 1.5:1, 1:1, 1:1.5, and 1:2 were synthesized via controlled polymerization and integrated into a PEDOT (poly(3,4-ethylenedioxythiophene)) matrix. Electrochemical testing revealed that the 1:1 ratio composite exhibited a maximum specific capacitance of 32.1 F/g at 1 A/g, attributed to the synergistic effects of microphase-separated dual continuous networks and porous structures. Multiscale characterization (XPS, SEM, TEM, AFM, BET, and contact angle measurements) revealed that the 1:1 ratio forms optimal conductive pathways, interfacial doping, and ionic diffusion channels. This study establishes that block ratio engineering is an effective method for balancing conductivity and ionic pathways in conductive polymer-based supercapacitor electrode materials, providing a theoretical basis for high-performance energy storage materials.