Theoretical study on adsorption of sulfamethoxazole on rutile-TiO2 (110) surface using quantum chemical method

Abstract

The adsorption of sulfamethoxazole (SMX) molecule on rutile-TiO₂ (110) surface (r-TiO₂) is examined by using quantum chemical computations. This process is evaluated as chemisorption with associated energies ca. 20 kcal.mol^-1 and determined mainly by O‧‧‧Ti_5f electrostatic interactions. The stable configurations are observed in detail following the arrangement of SMX on r-TiO₂. The existence and role of surface interactions are clarified by AIM and NBO analyses upon complexation. It is noticeable that the stable interactions between SMX and r-TiO₂ are mainly focused on >S=O groups and Ti_5f sites. The hydrogen bonds of the N/C-H‧‧‧O_b type play an additional role in the stabilization of complexes.