Structure and magnetocaloric properties of La0.8Ag0.2−xKxMnO3 perovskite manganites

► La0.8Ag0.2−xKxMnO3 (0 ≤ x ≤ 0.15) compounds were crystallized with rhombohedral symmetry. ► Potassium substituted compounds exhibit a paramagnetic-ferromagnetic transition with decreasing temperature. ► A large magnetocaloric effect is observed in our samples. ► The maximum RCP value is about 258 J kg−1 under 5 T for La0.8Ag0.05K0.15MnO3 sample. ► These results make our compounds potential candidates for magnetic refrigeration.