Ultrapure water (resistivity
> 18.2 MΩ·cm, Millipore
Milli-Q) was used for all experiments
in this work. Prior to each experiment, all cell compartments were
cleaned by storing them in a potassium permanganate solution (1 g
L
–1 KMnO
4 (Fluka, ACS reagent) in 0.5
M H
2SO
4 (Fluka, ACS reagent)) overnight. The
solution was subsequently drained, and the cell compartments were
rinsed with a dilute piranha solution (1:3 v/v of H
2O
2 (Merck, Emprove exp)/H
2SO
4) to remove
residual KMnO
4 and MnO
x. Afterward,
the cell compartments were cleaned by repetitively rinsing and boiling
with
Milli-Q water to remove all inorganic contaminants. Electrolytes
were prepared from LiClO
4 (Sigma-Aldrich, ≥99.99%
trace metal basis), NaClO
4 (Sigma-Aldrich, ≥99.99%
trace metal basis), KClO
4 (Sigma-Aldrich, ≥99.99%
trace metal basis), NaClO
4 (Sigma-Aldrich, ≥99.99%
trace metal basis), H
2SO
4 (Merck,
Suprapur,
96%), PdSO
4 (Sigma-Aldrich, 99.99% trace metal basis),
and HClO
4 (Sigma-Aldrich, Ultrapure, 70%). In this work,
a Pt wire (0.5 mm diameter, MaTecK, 99.9%) was used as the counter
electrode, a reversible hydrogen electrode (RHE) was used as the reference
electrode, and all of the potentials were corrected for ohmic drop
and controlled with an Autolab PGSTAT302N potentiostat.
Ye C., Dattila F., Chen X., López N, & Koper M.T. (2023). Influence of Cations on HCOOH and CO Formation during CO2 Reduction on a PdMLPt(111) Electrode. Journal of the American Chemical Society, 145(36), 19601-19610.