114
nanowires is described in detail in Ref. [28]. To prepare Pd 1 − x Au x NWs with control
over chemical composition, a mixed precursor solution containing both Pd
2+
and
Au
3+
precursors is reacted with sodium borohydride serving as a reducing agent, and
the nucleation and growth of NWs are directed by the presence of the surfactant.
The composition of the NWs can be readily and predictably controlled by manipulating the contents of the precursor solution.
A selective CO adsorption was employed to remove residual organic impurities
from the surface of the ultrathin Pd 1 − x Au x NW/C catalysts. The electrode was
cycled in 0.1 M HClO 4 up to a potential of 1.3 V at a rate of 100 mV/s until a stable
profile was obtained. Thereafter, the electrode was immersed in a CO-saturated
electrolyte for 30–45 min so as to selectively displace residual organic impurities
from the surface of the NWs. In a deoxygenated electrolyte, voltammetric CO stripping was performed by potential excursion up to 1.15 V. Pt atoms are deposited by
galvanic displacement of a Cu UPD monolayer.
Fig. 8.9 Representative TEM image (a) of Pd 9 Au NWs supported on Vulcan XC-72R carbon support. The inset to (a) shows a typical high-resolution TEM image, highlighting the segmented
nature of the individual NW. The SAED pattern (b) obtained from a collection of NWs is highlighted. The concentric rings of a simulated diffraction pattern for FCC Pd 9 Au are shown as an
overlay to the experimentally determined SAED pattern. A high-angle annular dark-field (HAADF)
image taken from a representative collection of Pd 8 Au 2 NWs is shown in (c). Characteristic EDAX
spectra (d) collected from various Pd 1 − x Au x NW/C composites. Reproduced from [28] with permission of American Chemical Society
8 Catalytic Properties of Pt Monolayer Electrocatalysts
nanowires is described in detail in Ref. [28]. To prepare Pd 1 − x Au x NWs with control
over chemical composition, a mixed precursor solution containing both Pd
2+
and
Au
3+
precursors is reacted with sodium borohydride serving as a reducing agent, and
the nucleation and growth of NWs are directed by the presence of the surfactant.
The composition of the NWs can be readily and predictably controlled by manipulating the contents of the precursor solution.
A selective CO adsorption was employed to remove residual organic impurities
from the surface of the ultrathin Pd 1 − x Au x NW/C catalysts. The electrode was
cycled in 0.1 M HClO 4 up to a potential of 1.3 V at a rate of 100 mV/s until a stable
profile was obtained. Thereafter, the electrode was immersed in a CO-saturated
electrolyte for 30–45 min so as to selectively displace residual organic impurities
from the surface of the NWs. In a deoxygenated electrolyte, voltammetric CO stripping was performed by potential excursion up to 1.15 V. Pt atoms are deposited by
galvanic displacement of a Cu UPD monolayer.
Fig. 8.9 Representative TEM image (a) of Pd 9 Au NWs supported on Vulcan XC-72R carbon support. The inset to (a) shows a typical high-resolution TEM image, highlighting the segmented
nature of the individual NW. The SAED pattern (b) obtained from a collection of NWs is highlighted. The concentric rings of a simulated diffraction pattern for FCC Pd 9 Au are shown as an
overlay to the experimentally determined SAED pattern. A high-angle annular dark-field (HAADF)
image taken from a representative collection of Pd 8 Au 2 NWs is shown in (c). Characteristic EDAX
spectra (d) collected from various Pd 1 − x Au x NW/C composites. Reproduced from [28] with permission of American Chemical Society
8 Catalytic Properties of Pt Monolayer Electrocatalysts