One-Step Construction of Biocompatible Glycine Assemblies with Exceptional Piezoelectric Performance for Sustainable Electronics

Glycine-based piezoelectric devices hold significant potential in implantable transient bioelectronics due to their biodegradability, easy accessibility, and high predicted piezoelectric responsiveness. However, challenges such as difficulties in large-scale crystal orientation alignment and weak piezoelectricity hinder their practical application. This paper proposes an innovative, simple one-step fabrication method using mussel-inspired dopamine (DA) molecules to synergistically prepare glycine-based devices with exceptional piezoelectric performance. It is found that DA can induce the formation of piezoelectric β-glycine crystals on various substrates via supramolecular interactions, achieving a maximum piezoelectric coefficient of 5.9 pC N −1 and piezoelectric voltage coefficient of 153 × 10 −3 V m N −1 in DA/glycine/polydimethylsiloxane films, with significantly enhanced thermal stability (≈120 °C). Furthermore, dopamine molecules can regulate the preferential crystal plane alignment of γ-glycine in polyvinyl alcohol (PVA)/glycine films, increasing their piezoelectric coefficient and voltage coefficient to 10.8 pC N −1 and 369 × 10 −3 V m N −1 , respectively. Using flexible glycine-based  films, piezoelectric force biosensors are fabricated that demonstrate exceptional sensing capabilities for joint flexibility and oral occlusion contact patterns. Additionally, DA/glycine crystals and DA/PVA/glycine films exhibit excellent biocompatibility and biodegradability. This work offers a simple, efficient, and energy-saving approach for fabricating sensitive glycine-based piezoelectric devices, enhancing the application potential of high-performance piezoelectric biomaterials in sustainable bioelectronics.