In this study, g-C3N4-Cu2O was successfully synthesized in the presence of PEG-400 surfactant via an acid treatment hydrothermal method and a high-temperature calcination method. The structures and properties of as-synthesized samples were characterized using a range of techniques, such as XPS, TEM, PL and BET. The g-C3N4-Cu2O heterojunction exhibits the enhanced photocatalytic performance and high stability. It is revealed that the addition of PEG can promote the heterojunction effect of g-C3N4-Cu2O, effectively improving the crystallinity and specific surface area of the photocatalyst, separation efficiency of photocarriers, and light absorption, thus enhancing the photocatalytic performance. (C) 2018 Published by Elsevier B.V.