Precursor Engineering Strategy Toward the Construction of Intrinsically Flexible Porous Carbon Monoliths for Deformable Supercapacitors

Abstract

Developing high-performance, flexible carbon electrodes for deformable supercapacitors is often hindered by trade-offs between porosity, conductivity, and mechanical resilience. Direct pyrolysis of flexible polymer precursors offers a simple route, yet the resulting carbons typically suffer from inadequate surface area or structural brittleness. To overcome these limitations, a facile precursor engineering strategy is proposed for constructing flexible, monolithic porous carbon via the pyrolysis of zinc-anchored amidoximated polyacrylonitrile felt. Chemical functionalization of polyacrylonitrile felt with amidoxime, amide, and carboxylate groups promotes low-temperature crosslinking and gradual thermal decomposition during carbonization, effectively suppressing shrinkage and preserving flexibility. Concurrently, amidoxime groups provide uniform anchoring sites for zinc ions through coordination complexation. During carbonization, a high specific surface area with hierarchical porosity is created through the dynamic templating effect of evaporating zinc species. The optimized carbon electrode demonstrates robust mechanical integrity and high electrochemical performance, achieving a specific capacitance of 1.47 F cm⁻² at 1 mA cm⁻². Furthermore, a quasi-solid-state symmetric supercapacitor assembled using flexible porous carbon felt electrodes delivers 0.88 F cm⁻² and maintains stable operation under substantial bending and folding deformation. This work demonstrates a practical approach for producing flexible, high-performance carbon electrodes, with significant potential for wearable and deformable energy storage applications.