alpha-Fe2O3/CaFe2O4 p-n heterojunctions were prepared via a simple in-situ hydrolysis process as highly efficient VOCs degradation photocatalyst, wherein no additional conditions such as high pressure, high temperature and surfactants were required. The structures and morphologies of the as-prepared samples were analyzed by XRD, SEM and TEM. The results revealed that alpha-Fe2O3/CaFe2O4 p-n heterojunctions exhibited superior photocatalytic activity of VOCs degradation compared to pure CaFe2O4 and alpha-Fe2O3 in both steady model and flow bed model. It can degrade more than 82% of acetaldehyde within 180 min in steady mode and 65% in flow mode under visible light irradiation. The prominent VOCs remove property could be attributed to the strong interfacial contact caused by the in-situ fabrication process and the promoted charge carrier separation efficiency due to the constructing of alpha-Fe2O3/CaFe2O4 p-n heterojunction. It provides some new insights into the design and fabrication of advanced photocatalytic materials with p-n heterojunction for high efficiency in VOCs photodegradation. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.