Multi-scale study of cobalt adsorption on TiO2 anatase (101): From DFT to force-field parameterization

Abstract

Understanding metal–support interactions (MSI) is critical for designing stable and efficient catalysts, such as cobalt catalysts on TiO2, commonly employed in Fischer–Tropsch synthesis. This study investigates cobalt adsorption on the TiO2 anatase (101) surface through a computational approach, combining density functional theory (DFT), ab initio molecular dynamics (AIMD) simulation, and genetic algorithm-based force field parameterization. It is shown that Co clusters get substantially oxidized due to interaction with oxygen atoms of the support. The parameterization of Morse potential force field is achieved using an automated and combined genetic algorithm (GA) - molecular dynamics (MD) simulation approach, leveraging AIMD simulations to capture the dynamic nature of MSI effectively in the training dataset. This method incorporates simulations with the Large-scale Atomic/Molecular Massively Parallel Simulator into the GA framework, thereby streamlining the optimization process for the force field, facilitating an efficient exploration of the parameter space. This new force field, validated against DFT results, offers an efficient tool for modeling MSI at larger length scales and longer timescales. Our findings highlight how MSI influences cobalt cluster stability, electron transfer, and surface restructuring, directly impacting catalytic performance and resistance to sintering. The methodology presented in this study offers a versatile framework that can be adapted to other metal–support systems with system-specific reparameterization and validation, enabling comprehensive investigation of mesoscale MSI studies on explicit oxide surfaces, facilitating further advances in heterogeneous catalysis research and applications. The findings highlight the influence of MSI on cobalt cluster stability, electron transfer, and surface reconstruction, all of which are crucial to catalytic activity and sintering resistance.