Adsorption, self-assembly and self-metalation of tetra-cyanophenyl porphyrins on semiconducting CoO(100) films

•Preparation and characterization of high-quality, semiconducting, epitaxial rs-CoO(100) films on Au(111).•A cyano-functionalized porphyrin adsorbs flat-lying on rs-CoO(100), self-assembles into well-ordered structures and self-metalates at 420 K.•Electronic states of the adsorbed molecule are identified by scanning tunneling spectroscopy.•Adsorption geometry, intermolecular forces, and electronic states are analyzed with the help of density functional theory.