Detailed study of Al2O3, an insulator with the band gap of about 8.7 eV, and its different organic/inorganic charge transfer complexes with visible-light photo activity is presented. In particular, prepared Al2O3 particles of the size 0.1-0.3 mu m are coated with several organic complexes - the specific details for catecholate- and salicylate-type of ligands are described below - and the light absorption properties and photocatalytic activity of such hybrids are scrutinized and compared with those of other organic/inorganic hybrid materials previously studied. In addition, the obtained experimental results are supported with quantum chemical calculations based on density functional theory. (C) 2017 Elsevier B.V. All rights reserved.