%0 Journal Article %1 fronzi2019theoretical %A Fronzi, Marco %A Assadi, M. Hussein N. %A Hanaor, Dorian A H %D 2019 %J Applied Surface Science %K CeO2 Hydrophobic ceria earth oxides rare surfaces %P 68-74 %R 10.1016/j.apsusc.2019.01.208 %T Theoretical insights into the hydrophobicity of low index CeO2 surfaces %U https://www.researchgate.net/publication/330633086_Theoretical_insights_into_the_hydrophobicity_of_low_index_CeO2_surfaces %V 478 %X The hydrophobicity of CeO2 surfaces is examined here. Since wettability measurements are extremely sensitive to experimental conditions, we propose here a general approach to obtain contact angles between water and ceria surfaces of specified orientations based on density functional calculations. In particular, we analysed the low index surfaces of this oxide to establish their interactions with water. According to our calculations, the CeO2 (111) surface was the most hydrophobic with a contact angle of Θ = 112.53° followed by (100) with Θ = 93.91°. The CeO2 (110) surface was, on the other hand, mildly hydrophilic with Θ = 64.09°. By combining our calculations with an atomistic thermodynamic approach, we found that the O terminated (100) surface was unstable unless fully covered by molecularly adsorbed water. The dissociative adsorption of water at the lower-energy (111) surface further results in the stabilisation of oxygen vacancies, which has implications in the catalytic activity of this plane. The findings here shed light on the origin of the intrinsic wettability of rare earth oxides in general and CeO2 surfaces in particular, and also explain why CeO2 (100) surface properties are so critically dependant on applied synthesis methods. https://www.sciencedirect.com/science/article/pii/S0169433219302399

@article{fronzi2019theoretical, abstract = {The hydrophobicity of CeO2 surfaces is examined here. Since wettability measurements are extremely sensitive to experimental conditions, we propose here a general approach to obtain contact angles between water and ceria surfaces of specified orientations based on density functional calculations. In particular, we analysed the low index surfaces of this oxide to establish their interactions with water. According to our calculations, the CeO2 (111) surface was the most hydrophobic with a contact angle of Θ = 112.53° followed by (100) with Θ = 93.91°. The CeO2 (110) surface was, on the other hand, mildly hydrophilic with Θ = 64.09°. By combining our calculations with an atomistic thermodynamic approach, we found that the O terminated (100) surface was unstable unless fully covered by molecularly adsorbed water. The dissociative adsorption of water at the lower-energy (111) surface further results in the stabilisation of oxygen vacancies, which has implications in the catalytic activity of this plane. The findings here shed light on the origin of the intrinsic wettability of rare earth oxides in general and CeO2 surfaces in particular, and also explain why CeO2 (100) surface properties are so critically dependant on applied synthesis methods. https://www.sciencedirect.com/science/article/pii/S0169433219302399}, added-at = {2019-08-28T16:39:59.000+0200}, author = {Fronzi, Marco and Assadi, M. Hussein N. and Hanaor, Dorian A H}, biburl = {https://www.bibsonomy.org/bibtex/2ac9535287a7168d209c7d15562699276/dohan}, doi = {10.1016/j.apsusc.2019.01.208}, interhash = {c3b54af0d189a860c0fac612e2857f5a}, intrahash = {ac9535287a7168d209c7d15562699276}, journal = {Applied Surface Science}, keywords = {CeO2 Hydrophobic ceria earth oxides rare surfaces}, pages = {68-74}, timestamp = {2019-09-28T19:22:30.000+0200}, title = {Theoretical insights into the hydrophobicity of low index CeO2 surfaces}, url = {https://www.researchgate.net/publication/330633086_Theoretical_insights_into_the_hydrophobicity_of_low_index_CeO2_surfaces}, volume = 478, year = 2019 }