Hierarchical P/YPO4 hollow microspheres are prepared by the reaction between amorphous red P and YCl3 aqueous solution via a hydrothermal method. The final product consists of crystalline YPO4 nanosheets and amorphous red phosphorus. Photocatalytic hydrogen formation measurements indicate that the P/YPO4 composites exhibit higher activity than the individual components. The composite with 53 wt% YPO4 is up to 6 times more active than red phosphorus under visible light irradiation. The formation mechanism of hierarchical microspheres and the enhanced photocatalytic activity are discussed. (C) 2012 Elsevier B.V. All rights reserved.