For example:
In an electrochemical cell utilising a platinum (Pt) anode, what is the difference and what kind of implications would be expected from using either Pt(100), Pt(110) or Pt(111)?
Density functional theory has reported the existence of weaker interaction of oxygen with Pt{100} compared to Pt{111} (and Pt{110}). It has also suggested that Pt{111} has the strongest adsorption energy for oxygen of the three basal planes. Studies in aqueous media (0.1 M HClO4 or 0.1 M KOH) have also pointed out that Pt{100} is the least active surface.
Dear Hayden Cartmill
The orientation of the Pt(hkl) has a strong influence on electrochemical reactions, The differences in CV is obvious as you can see in the attached file (0.05 M H2SO4).
See for example:
Article Temperature-dependent oxygen electrochemistry on platinum lo...
Article Surface electrochemistry of CO on Pt(110)-(1 × 2) and Pt(110...
Article Temperature-Dependent Hydrogen Electrochemistry on Platinum ...
Density functional theory has reported the existence of weaker interaction of oxygen with Pt{100} compared to Pt{111} (and Pt{110}). It has also suggested that Pt{111} has the strongest adsorption energy for oxygen of the three basal planes. Studies in aqueous media (0.1 M HClO4 or 0.1 M KOH) have also pointed out that Pt{100} is the least active surface.
1. Different charge transfer kinetics. k0 ≈ 104.5, 103.4, and 104.8 s−1 for hydrogen adsorption on Pt(111), Pt(100), and Pt(110), respectively, and k0 ≈ 104.7 s−1 for OH adsorption on Pt(111)
2. A clear effect of the surface structure on the potential of water orientation, being 0.37 for Pt(111), 0.33 for Pt(100), and 0.14 V for Pt(110) in 0.1 M HClO4 solution.
3. According to Garcia et al., the potential of water reorientation exhibit a different pH dependency for the three basal planes, shifting 0.060 for Pt(111), 0.030 for Pt(100), and 0.015 V/dec for Pt(110). Comparison of these results with charge density data sheds light into the chemical and electrostatic effects governing the reorientation of the interfacial water network. It is concluded that water on Pt(111) exhibits a small net orientation in the absence of electric field at the interphase. On the other hand, the lack of free charge density data for Pt(100) and Pt(110) limits the interpretation of the experimental results.
Reference: J. Phys. Chem. C 2009, 113, 21, 9290–9304
(https://doi.org/10.1021/jp900792q)
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