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(Zr0.2Ti0.8)O3–0.4(Ba0.7Ca0.3)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.