Examination of Ostwald ripening in the photocatalytic growth of silver nanoparticles on titanium dioxide coatings

• Published in: Applied surface science Vol. 373; pp. 38 - 44
• Main Authors: Piwoński, Ireneusz, Spilarewicz-Stanek, Kaja, Kisielewska, Aneta, Kądzioła, Kinga, Cichomski, Michał, Ginter, Joanna
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.06.2016
• Subjects: Coalescing; Coatings; Illumination; Nanoparticles; Ostwald ripening; Photochemical; Scanning electron microscopy; Scanning electron microscopy (SEM); Silver nanoparticles (AgNPs); Titanium dioxide; Titanium dioxide (TiO2); Silver nanoparticles (AgNPs); Ostwald ripening; Scanning electron microscopy (SEM); Titanium dioxide (TiO2)
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.01.131

The growth of silver nanoparticles (AgNPs) according to Ostwald ripening process. •Silver nanoparticles were grown on the sol–gel TiO2 coating by photoreduction of silver ions at short illumination times.•Size and number of nanoparticles were measured using scanning electron microscopy.•Large nanoparticles grow at the expense of small nanoparticles according to Ostwald ripening mechanism. Silver nanoparticles (AgNPs) were grown on the surface of titanium dioxide coating (TiO2) using a photochemical method. The size and number of AgNPs were monitored using scanning electron microscopy (SEM) after 20, 30, 180 and 300s of UV illumination. It was found that for short illumination times (20s) a significant number of small nanoparticles were grown. However, after an additional 10s of illumination, small nanoparticles were subject to decomposition and the released Ag+ ions were utilized for the growth of the existing larger nanoparticles, causing an increase in their dimensions. The observed results indicate that the nucleation and further growth of AgNPs proceed according to Ostwald ripening. For longer illumination times (180, 300s) a coalescence of closely located particles was observed.