Paper NS+SP-TuM13
Low-Temperature Atomic Layer Deposition of Crystalline Platinum Nanoclusters on Graphene Nanoplatelets Using (Methylcyclopentadienyl)-Trimethylplatinum and Oxygen

Tuesday, October 20, 2015, 12:00 pm, Room 212B

The thermal atomic layer deposition of platinum using (methylcyclopentadienyl)-trimethylplatinum (MeCpPtMe₃) and oxygen has been investigated for more than a decade and performed on various supports, including flat surfaces [1, 2], nanoparticles [3], nanowires [4] and carbon-based nanomaterials [5, 6, 7, 8]. It has been demonstrated and widely accepted that this ALD process has a lower limit of deposition temperature of 200 °C. Here, we demonstrate the thermal Pt ALD on graphene nanoplatelets using MeCpPtMe₃ and dry air (20% wt. O₂), and show that highly dispersed and crystalline Pt nanoparticles can be obtained at a temperature as low as 80 °C. The feasible low-temperature deposition is attributed to the role of the graphene support that can activate molecular oxygen to form O₂^- anions [9], which consequently enhances the oxidation reactions in ALD. Importantly, the low deposition temperatures (i.e., 80 °C and 100 °C) can prevent the ripening of nanoparticles and hinder the formation of new nuclei during the ALD, allowing for better control in particle size and distribution. In contrast, at higher temperatures (150-250 °C), the ripening occurs, and new nuclei are constantly formed during the deposition, resulting in a broader particle size distribution.

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