Table 2.
Weight percentages of Pt, C, and O of samples processed at different carrier gas flow rates and a constant substrate temperature of 350 °C without the addition of hydrogen gas measured by XPS. The degree of oxidation of only the Pt-NPs (mainly Pt(OH)2) of individual samples is shown in parentheses under the platinum loading. The platinum loading and degree of oxidation of the whole Pt/CNW catalyst layers are dependent on the carrier gas flow rate during synthesis.
| Sample/Structure | Pressure [Pa] |
Carrier gas flow rate [sccm] |
Pt [wt%] (Pt0/PtII [%]/[%]) |
C [wt %] |
O [wt %] |
| P6/CNWs | 14.5 | 30 | 7.6 (51/49) |
88.4 | 4.0 |
| P2/CNWs | 14.5 | 60 | 7.6 (98/2) |
90.3 | 2.1 |
| P7/CNWs | 14.5 | 93 | 15.0 (98/2) |
82.0 | 3.0 |