Photocurable 3D printing of flame-retardant bio-based polymers for customized triboelectric nanogenerators

Abstract The customized fabrication of triboelectric nanogenerator (TENG) demands innovative material strategies that synergistically achieve sustainability, flame retardancy, and optimal mechanical-electrical performance. Here, we present a bio-based thermoset resin derived from palm oil (PO) and phytic acid (PA), which integrates high-resolution LCD 3D printability, exceptional flame resistance, robust mechanical strength, and stable TENG performance. Through molecular engineering, we synthesized a methacrylated PO derivative (MPOEA) and a PA-based methacrylate monomer (GPA) to enable UV-induced crosslinking while maintaining low viscosity (<42 mPa·s) and near-complete C = C conversion (96.8%), ensuring structural integrity and print fidelity. Notably, the phosphate esters in GPA impart a synergistic flame-retardant mechanism, combining condensed-phase barrier formation and gas-phase radical quenching. Additionally, the material exhibits efficient TENG functionality, generating a stable output of 8 V at 3 Hz over 15,000 cycles, which underscores its suitability for self-powered sensors and wearable electronics. This work establishes a feasible method for developing sustainable, multifunctional photopolymers that overcome traditional performance limitations in electronics.