Modification of The Electronic and The Adsorption Properties of Epitaxial Delafossite CuFeO$_{\mathrm{2}}$ thin films by The Substitution of Fe by Ga

We studied the chemisorption properties of CuFeO$_{\mathrm{2}}$ and CuFe$_{\mathrm{1-x}}$GaxO$_{\mathrm{2}}$ delafossite thin film samples with respect to H$_{\mathrm{2}}$O and CO$_{\mathrm{2}}$ using thermal programmed desorption. Adsorption of CO$_{\mathrm{2}}$ and H$_{\mathrm{2}}$O was observed on both surfaces by X-Ray photoelectron spectroscopy. Substituting Fe by Ga in CuFeO$_{\mathrm{2}}$ leads to reduced amount of adsorbed H$_{\mathrm{2}}$O with respect to CO$_{\mathrm{2}}$. Additionally, NIR-Vis Transmittance and Reflectance spectroscopies were used to show changes in sample surface optical absorption properties in response to CO2/H2O exposure using a pressure range 0-90 kPa.