Plasma oxidation-induced microstructural evolution of silver oxide on silver thin lamellae

Silver oxide (Ag₂O) is valued for its antibacterial properties and high conductivity in applications like catalysis, sensors, and electronics. However, a significant knowledge gap remains regarding the growth mechanisms and characteristics of Ag₂O thin films, highlighting the need for further research to optimize their performance. This study investigated plasma oxidation-induced microstructural evolution of Ag₂O on silver thin lamellae. We used a position-tracking function in a transmission electron microscope to examine the nucleation mechanisms, growth dynamics, and structural transformations during oxidation. The process initially formed nanoscale Ag₂O clusters that were identified through high-resolution transmission electron microscopy, fast Fourier transform analysis, and energy-dispersive X-ray spectroscopy. Nucleation of Ag₂O resulted in nanopitting in the silver matrix, leading to distinct oxide clusters. The coalescence of these clusters produced a porous oxide structure driven by lattice mismatch and continuous structural distortion at the Ag/Ag₂O interface. Further oxidation induced the transformation of silver grains into Ag₂O nanoparticles with random crystalline orientations, as confirmed by selected area electron diffraction patterns. The observed microstructural modifications provide key insights into the oxidation behavior of silver and suggest pathways for tailoring silver oxide nanostructures for applications in catalysis, electronics, and sensors.