Photocatalysis　is　a green　chemical　process　that　could　partly　solve　energy　and　pollution　issues.　Catalysts　such　as　cobalt　titanate,　CoTiO3,　have　intrigued　scientists　due　to　a　visible　light-responsive　band　gap　of　about　2.3 eV　and　a　high　valance　band　potential　of　about　2.35 eV　that　allow　a　remarkable　oxidative　activity.　Nonetheless,　CoTiO3　photocatalytic　activity　is　limited　by　charge　recombination,　thus　requiring　modifications.　For　instance,　the　introduction　of　a second　semiconductor　allows　improved　charge　separation　and　notable　enhancement　of　the　activity.　Here　we　review　interfacial　engineering　of　CoTiO3　by　introduction　of　a　second　semiconductor.　We　describe　the　synthesis　and　photocatalytic　applications　of　bare　and　modified　CoTiO3.　Modified　CoTiO3　composites　are　categorized　into　Type-I,　Type-II,　Z-scheme,　and　S-scheme　heterojunctions,　depending　on　the　band　structures　of　the　composite.　©　2022,　The　Author(s),　under　exclusive　licence　to　Springer　Nature　Switzerland　AG.