“…Double perovskite (A 2 B′B″O 6 ) represents a unique class of materials for electrode materials in batteries, sensors, and fuel cells. − These ternary compounds exhibit a wide range of physical and chemical properties, i.e., intersite charge transfer, disproportionation, and phase transformation. − When the difference of charge or ionic radii between B′ and B″ cations are greater, double perovskites have ordered structures. , A 2 B′B″O 6 with rare-earth B′ and B″ cations attracts widespread attention, due to geometric magnetic frustration and high-quality superconducting thick films . Recently, reports of double perovskites continue to exhibit significant progress in magnetic order , and photoluminescence properties. , For example, the antiferromagnetic order of Ni 2+ ion moments is determined by Ln = La, Pr, Nd, Sm, Eu, Gd, and Tb in double perovskite NaLnNiWO 6 in the range of 23–30 K .…”