“…[9][10][11][12][13] While 4d or 5d transition metal based layered perovskite structures of Dion-Jacobson, Ruddlesden-Popper and Aurivillius phases are obtained by the exfoliation method, 9 the exploration of other 2D perovskite oxide systems with strongly correlated d-orbital electrons is impeded by the expensive physical techniques. Equipped with exotic properties such as high oxygen mobility, extensive stoichiometric range, redox exibility and thermal stability, the applications of perovskites span a rich spectrum of high temperature superconductivity, 14 colossal magnetoresistance, 15,16 ferroelectricity, 17 high dielectric constant, 18 sensing, 1 fuel cells, 19,20 electrocatalytic conversion, 21,22 and storage. 23,24 Planar manifestation of this outstanding class of complex oxides, especially with rst row transition metals, by avant-garde methods is expected to imbibe state-of-the-art fundamental properties leading to newer functionalities and devices.…”