In this work, we report the synthesis, crystal structure determination, and properties of three decavanadates, i.e., (NH4)2[Co(H2O)5(β-HAla)]2[V10O28]·4H2O (1), (NH4)2[Ni(H2O)5(β-HAla)]2[V10O28]·4H2O (2), and (NH4)2[Cd(H2O)5(β-HAla)]2[V10O28]·2H2O (3)...