Modulating the Formation and Evolution of Surface Hydrogen Species on ZnO through Cr Addition

• DOI: 10.1021/acscatal.2c00978
• Publication Date: 2022-05-11T19:10:58Z
• Authors: Aiyi Dong; Le Lin; Rentao Mu; Rongtan Li; Kun Li; Chao Wang; Yunjun Cao; Yunjian Ling; Yuxiang Chen; Fan Yang; Xiulian Pan; Qiang Fu; Xinhe Bao
• Keywords: Thermal desorption spectroscopy

Formation and evolution of active hydrogen species from H2 on a metal oxide is great importance in many hydrogenation reactions, while understanding the nature surface remains challenge. Herein, high-vacuum-based transmission infrared spectroscopy coupled with temperature-programmed desorption has been applied to study over ZnO ZnCrOx catalysts. We show that D2 dissociates readily form Zn–D O–D at 153 K, simultaneous occurs 223 K. This corroborates reversible dissociation recombination ZnO. (Cr−)Zn–D (Cr−)O–D appear ZnCr2O4 273 indicating higher barrier for activation than can diffuse 573 then O-D groups requires temperature 943 Theoretical studies demonstrate geometry plays crucial role species. The polar ZnCr2O4(111) stabilize metal-H due high its diffusion thermodynamic obstruction association O–H, contrast nonpolar ZnO(101̅0) surface. These results provide insights into tuning stability catalysts, which will contribute tailoring processes H-involved catalytic reactions.