CNT-modified BCZT/P(VDF-TrFE) composites for high-performance flexible PENGs

Flexible piezoelectric nanogenerators (PENGs) are attractive for self-powered electronics, yet their practical deployment is often limited by insufficient electrical output. Here, we report a dual-filler strategy for enhancing lead-free flexible PENGs based on BCZT/P(VDF-TrFE) composites, in which 0.6Ba(Zr_0.2Ti_0.8)O₃–0.4(Ba_0.7Ca_0.3)TiO₃ (BCZT) provides the primary piezoelectric contribution and carbon nanotubes (CNTs) improve charge transport and interfacial electromechanical coupling. Structural characterization confirmed the successful incorporation of both fillers while preserving the electroactive β phase of P(VDF-TrFE). Among all compositions, the 0.1-wt% CNT–3-wt% BCZT/P(VDF-TrFE) composites exhibit the best electrical output performance, delivering 13 µA and 50 V under 175 N at 5 Hz, with a maximum power density of 23 µW cm⁻². In addition, the composites also maintain stable electrical output over 15,000 loading cycles. These results demonstrate that synergistic BCZT/CNT incorporation is an effective approach for improving the output performance and durability of flexible lead-free PENGs for energy-harvesting and self-powered sensing.