TY - JOUR
T1 - Catalytic Activity and Water Stability of the MgO(111) Surface for 2-Pentanone Condensation
T2 - Article No. 120234
AU - Vardon, Derek
AU - Huo, Xiangchen
AU - Conklin, Davis
AU - Zhou, Mingxia
AU - Vorotnikov, Vasseli
AU - Assary, Rajeev
AU - Purdy, Stephen
AU - Page, Katharine
AU - Li, Zhenglong
AU - Unocic, Kinga
AU - Balderas, Raiven
AU - Richards, Ryan
PY - 2021
Y1 - 2021
N2 - Nanomaterials derived from earth-abundant metal oxides have gained tremendous interest as catalysts; although, water stability remains a challenge. This study examines MgO(111) surfaces for 2-pentanone condensation and their evolution during D2O hydration. Catalyst screening confirmed the high activity of fresh MgO(111) for 2-pentanone condensation relative to conventionally prepared MgO(100). Computational modeling suggests that the (111) surface is readily hydroxylated, and that surface hydroxyls help stabilize the surface and reduce the barrier for 2-pentanone condensation. Vapor-phase D2O hydration after 3 min increased MgO(111) hydroxyls and retained surface area and activity; however, after 1 h, deuteroxide formation reduced the surface area and activity by >30 %. After 24 h, deuteroxide growth slowed down, and surface area and activity remained stable. This suggests MgO(111)-derived hydroxide may be the dominant surface responsible for 2-pentanone condensation following water exposure. Thermal regeneration of the 24-h sample restored 86 % of the surface area and 94 % of the activity.
AB - Nanomaterials derived from earth-abundant metal oxides have gained tremendous interest as catalysts; although, water stability remains a challenge. This study examines MgO(111) surfaces for 2-pentanone condensation and their evolution during D2O hydration. Catalyst screening confirmed the high activity of fresh MgO(111) for 2-pentanone condensation relative to conventionally prepared MgO(100). Computational modeling suggests that the (111) surface is readily hydroxylated, and that surface hydroxyls help stabilize the surface and reduce the barrier for 2-pentanone condensation. Vapor-phase D2O hydration after 3 min increased MgO(111) hydroxyls and retained surface area and activity; however, after 1 h, deuteroxide formation reduced the surface area and activity by >30 %. After 24 h, deuteroxide growth slowed down, and surface area and activity remained stable. This suggests MgO(111)-derived hydroxide may be the dominant surface responsible for 2-pentanone condensation following water exposure. Thermal regeneration of the 24-h sample restored 86 % of the surface area and 94 % of the activity.
KW - catalyst regeneration
KW - metal oxide hydration
KW - neutron total scattering
U2 - 10.1016/j.apcatb.2021.120234
DO - 10.1016/j.apcatb.2021.120234
M3 - Article
SN - 0926-3373
VL - 294
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
ER -