Bio‐Based Piezoelectrets from Polylactic Acid and Natural Waxes: A Sustainable Approach for Energy Harvesting

Conventional electret materials are mainly nonbiodegradable and derived from fluorinated compounds, representing a reasonable concern for the ambient. This study explores the development of biodegradable piezoelectrets based on the integration of natural waxes into polylactic acid (PLA). In particular, composites with carnauba, candelilla, and beeswax have been investigated employing innovative histological techniques for microstructural analysis. These bio‐based materials demonstrate an exceptional surface potential with values exceeding 2 kV and 80% of charge retention over 10 days, a significant improvement over PLA‐only electrets. Thermal analysis reveals enhanced crystallinity and nucleation effects imparted by waxes, while morphological studies confirm uniform dispersion and phase alignment under electric fields. The results highlight the synergistic interaction between PLA and wax domains, stabilizing dipoles, and enhancing performance. These biobased composites also exhibit charge retention recovery during operational cycles, positioning them as high‐performance candidates for sustainable energy harvesting and sensing applications. The findings represent a step forward in the design and development of eco‐friendly electrets.