Mapping and characterization of the surface structure and electronic properties of β-Ag2MoO4 from DFT thermodynamic calculations
Abstract: The physical and chemical properties of metal oxides are closely related to their surface termination, the presence of defects, and structural disorder, making the assignment of surface-morphology-property relationship difficult. The identification of specific descriptors that govern the surface properties is crucial to design new materials with customized compositions and structures. In this study, we investigated the relative stability and electronic properties of sixteen terminations of β-Ag2MoO4 (110), (111), and (011) surfaces, based on the calculated surface Gibbs free energies, by employing DFT calculations to obtain the Ag–Mo–O surface phase diagrams. We underscored how the local electronic structure has a profound influence on the work function and structural stability of surface terminations as function of thermodynamic equilibrium conditions, thus providing a critical factor for regulating the functional properties of this semiconductor. The values of the work function are very dependent of the surface terminations; thus the corresponding photocatalytic activity can be modulated by achieving thermodynamically favored surface terminations under appropriate conditions. Based on the analysis mentioned above, our results will help us know which surface terminations are stable under the thermodynamic equilibrium growth conditions and better understand their surfaces’ intrinsic properties. This study provides a solid foundation for engineering the intrinsic structural and electronic characteristics of future β-Ag2MoO4-based materials.
Author(s): T.T. Dorini; F. Lipsky; A. Rodrigues-Pinheiro; J. Andrés; E. Longo; M.A. San-Miguel
Surfaces and Interfaces
Published: 1 January 2025, Volume 56, 105530
DOI: https://doi.org/10.1016/j.surfin.2024.105530
CDMF
The CDMF, hosted at the Federal University of São Carlos (UFSCar), is one of the Research, Innovation and Dissemination Centers (RIDC) supported by the São Paulo State Research Support Foundation (Fapesp), and also receives investment from the National Council Scientific and Technological Development (CNPq), from the National Institute of Science and Technology of Materials in Nanotechnology (INCTMN).
