Four new triazole-decorated silver(I)-based cationic metal− organic frameworks (MOFs), {[Ag(L1)](BF 4 )} n (1), {[Ag(L1)](NO 3 )} n (2), {[Ag(L2)](BF 4 )} n (3), and {[Ag(L2)](NO 3 )} n (4), have been synthesized using two newly designed ligands, 3-fluoro-5-(4H-1,2,4-triazol-4-yl)pyridine (L1) and 3-(4H-1,2,4-triazol-4-yl)-5-(trifluoromethyl)pyridine (L2). When the fluorine atom was changed to a trifluoromethyl group at the same position, tremendous enhancement in the MOF dimensionality was achieved [twodimensional to three-dimensional (3D)]. However, changing the metal salt (used for the synthesis) had no effect. The higher electron-withdrawing tendency of the trifluoromethyl group in L2 aided in the formation of higherdimensional MOFs with different properties compared with those of the fluoro derivatives. The fluoride group was introduced in the ligand to make highly electron-deficient pores inside the MOFs that can accelerate the anionexchange process. The concept was proved by density functional theory calculation of the MOFs. Both 3D cationic MOFs were used for dye adsorption, and a remarkable amount of dye was adsorbed in the MOFs. In addition, owing to their cationic nature, the MOFs selectively removed anionic dyes from a mixture of anionic, cationic, and neutral dyes in the aqueous phase. Interestingly, the present MOFs were also highly effective for the removal of oxoanions (MnO 4 − and Cr 2 O 7 2− ) from water.