Description
Recent experimental results have shown Au nanoparticles (NP) in liquid Ga (liq-Ga) are excellent photocatalysts for benzyl alcohol conversion to benzaldehyde. When the Au NPs are placed in liq-Ga they develop an ultra-thin amorphous-GaOx (a-GaOx) skin/film which is expected to play an important role in the photoreaction. Therefore, understanding the reaction mechanism requires atomic level modelling of the a-GaOx film and it’s Au interface. Using molecular dynamics in LAMMPS [1] with a machine-learned potential [2] and the melt-quench process, we model stoichiometric a-GaO1.5 and non-stoichiometric a-GaO1.1 systems. The electronic properties such as the band alignment are studied using Density Functional Theory as implemented in CP2K [3] with a non-local exchange-correlation functional. Further modelling of O2 adsorption on a-GaOx is performed in VASP [4]. These models provide new insight into how hot electron injection from localised surface plasmon modes on the Au NP could facilitate a charge cycling mechanism between the Au-GaOx and liq-Ga layers and the benzyl alcohol conversion reaction is activated through superoxide anion creation near the GaOx film.
[1] Thompson, A. P. et. al. LAMMPS - a Flexible Simulation Tool for Particle-Based Materials Modeling at the Atomic, Meso, and Continuum Scales. Comput. Phys. Commun., 271, 108171 (2022)
[2] Zhao, J. et al. Complex Ga2O3 polymorphs explored by accurate and general-purpose machine-learning interatomic potentials. npj Comput. Mater. 9, 159 (2023)
[3] Kühne, T. D. et. al. CP2K: An Electronic Structure and Molecular Dynamics Software Package - Quickstep: Efficient and Accurate Electronic Structure Calculations. J. Chem. Phys. 2020, 152 (19), 194103.
[4] G. Kresse and J. Hafner, Phys. Rev. B 47 , 558 (1993); ibid. 49 , 14 251 (1994)., G. Kresse and J. Furthmuller, Comput. Mat. Sci. 6, 15 (1996)., G. Kresse and J. Furthmuller, Phys. Rev. B 54 , 11 169 (1996).
| I am the presenting author | Yes |
|---|