A natural glutathione peptide-based piezoelectric crystalline material for power harvesting and sensing

Peptides have been shown to self-assemble into non-centrosymmetric structures exhibiting piezoelectricity. However, the piezoelectricity of peptide self-assemblies remains underexplored. Herein, for the first time, we have explored the piezoelectricity of a natural glutathione (GSH) peptide-based crystalline material for power harvesting and biosensing. The crystal structure indicated that GSH self-assembles to form an antiparallel staggered supramolecular stacking pattern. Density functional theory calculations showed that GSH self-assemblies exhibited a maximum piezoelectric coefficient of 64.3 pC N^-1, which was one of the highest predicted values among peptide-based self-assemblies. The GSH assembly-based piezoelectric nanogenerator generated an open-circuit voltage of 5.02 V under an external force of 45 N, while maintaining stability over 6000 continuous press-release cycles. Furthermore, the GSH crystal-based self-powered sensor was successfully developed for effective monitoring of human joint bending. This study developed a novel natural tripeptide piezoelectric self-assembly, promoting the advancement of biomolecule-based piezoelectric supramolecular materials.