26th Australian Institute of Physics Congress and the Australian and New Zealand Conference on Optics and Photonics

Atomic Layer Deposition of AlOx Overlayer Prevents Agglomeration of Phosphine-Ligated Au9 Clusters on RF-sputtered TiO2 Films

Not scheduled

20m

Belinda Hutchinson Building (The University of Sydney )

Contributed Oral AIP | Condensed Matter & Materials (CMM)

Description

Maintaining the integrity of metal clusters is crucial to maintaining their unique, size-dependent properties but this is challenging as they tend to agglomerate when deposited onto a substrate. Coating metal clusters with a metal oxide layer is considered an effective approach to stabilise the clusters and prevent agglomeration. In the present work, phosphine-protected Au9 clusters deposited onto RF-sputtered titanium dioxide (RF-TiO2) films were coated with an ALD-AlOx overlayer using trimethylaluminum as precursor. ALD overlayers were deposited at 25 ⁰C, 100 ⁰C, 150 ⁰C, and 200 ⁰C to determine the most suitable temperature for forming an AlOx overlayer while preventing the agglomeration of the deposited Au9 clusters. It is shown that the ALD overlayer effectively prevents the agglomeration of the phosphine-protected Au9(PPh3)8(NO3)3 clusters deposited on TiO2 across the tested ALD layer formation temperatures, demonstrating the effectiveness of ALD overlayers for maintaining the size of the original Au9 clusters.