Development of highly-active photocatalyst is of critical challenge for hydrogen production from water reduction, and optimizing the microstructure and the composition of the relative materials is very necessary to obtain the high-quality catalysts. Here, a novel self-adjusting structure of pompoms-like cadmium molybdate nano-micro hybrid stimulated by copper ions (Cu-CdMoO4) was achieved. It was found that the morphology and property of the CdMoO4 can be modulated greatly by the Cu. The optimal H-2 generation amount for the hybrid was about 77.4 times higher than that of pure CdMoO4 under same conditions. The significantly improved activity is associated with wider light response, more active sites, and effective charge separation. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.