High-performance　inkjet-printed　nickel　oxide　thin-film　transistors　(TFTs)　with　Al2O3　high-k　dielectric　have　been　fabricated　using　a　sol-gel　precursor　ink.　The　＂coffee　ring＂　effect　during　the　printing　process　was　facilely　restrained　by　modifying　the　viscosity　of　the　ink　to　control　the　outward　capillary　flow.　The　impacts　on　the　device　performance　was　studied　in　detail　in　consideration　of　annealing　temperature　of　the　nickel　oxide　film　and　the　properties　of　dielectric　layer.　The　optimized　switching　ability　of　the　device　were　achieved　at　an　annealing　temperature　of　280　degrees　C　on　a　50-nm-thick　Al2O3　dielectric　layer,　with　a　hole　mobility　of　0.78　cm(2)/V.s,　threshold　voltage　of　-0.6　V　and　on/off　current　ratio　of　5.3　x　10(4).　The　as-printed　p-type　oxide　TFTs　show　potential　application　in　low-cost,　large-area　complementary　electronic　devices.　(C)　2018　Elsevier　B.V.　All　rights　reserved.