Variable-temperature scanning tunneling microscopy and computational studies examining water and potassium adsorption on Au(100)

The coadsorption of water and potassium on a Au(100) surface is examined using variable-temperature Scanning Tunneling Microscopy (STM). The two-layer system initially formed on the reconstructed Au(100) through addition of K is converted into a labyrinthine row structure upon the introduction of water. This structure features KOH molecules likely covered with a water adlayer. Density Functional Theory (DFT) calculations provide further insight into the observed labyrinthine striped structures formed by adsorbed KOH. Images obtained following limited introduction of water feature larger unreacted areas and a more disordered row structure.