Correlation between organic residuals of green synthesized nanoparticles and resistive switching behavior†

In this work, ZnO nanoparticles (NPs) are synthesized using avocado seed extract and annealed at different annealing temperatures from 400 to 800 °C. The morphology of the nanoparticles changes from poly shapes at 400 °C to spherical ones at 800 °C, and particle sizes increase from ∼42 nm to ∼128 nm. The Ag/ZnO@400/FTO memory device exhibits stable resistive switching over 100 cycles and a resistance window of approximately 150. Also, the performance characteristics of ZnO@600 and ZnO@800-based devices are degraded gradually over operating cycles. The concentration of oxygen interstitials (O_i) in ZnO nanoparticles, which may originate from organic residues, decreases as the annealing temperature increases. These O_i ions reduced the energy barrier at the interfaces, facilitating electron transport under an external electric field. This study has demonstrated the close correlation between resistive switching characteristics and organic residuals in green synthesized nanoparticles.