A Perovskite-like structure and its device applications are disclosed. One Perovskite-like structure disclosed includes a compound having an empirical chemical formula [A(ByC1-Y)Oz]x, where x, y, and z are numerical ranges. In select embodiments, A comprises one or more divalent metal ions, B comprises one or more monovalent metal ions, C comprises one or more pentavalent metal ions, O is oxygen; and wherein x≧1, 0.1≦y≦0.9, 2.5≦z≦3, and wherein the net charge of A is +2, and the net charge Of (ByC1-y) is +4.