02272nas a2200277   4500008004100000022001400041245014400055210006900199260000800268300001100276490000800287520127700295653002101572653002101593653003001614653003001644653001501674653002701689100002901716700002101745700002201766700002701788700002701815700002201842856013001864       2022                        eng d  a0169-433200aSurface alteration driven bi-functional catalytic activity of alkali niobate-N doped graphene composite for exalted oxygen electrochemistry0 aSurface alteration driven bifunctional catalytic activity of alk  cAPR  a1521600 v5803 aIn this work, we establish that surface reconstruction, oxygen vacancies —specifically those located on the catalyst surface, and high crystallinity can be effective in tuning the catalytic activity of perovskite oxides. We report a high-performance electrocatalyst with an orthorhombic perovskite structure (NaNbO3), having an anisotropic surface layer and high crystallinity that exhibits superior activity and durability for the bi-functional oxygen electrochemistry compared to that of a similar perovskite composition with an isotropic surface layer and low crystallinity. The improvement in the electrocatalytic activity for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is mainly attributed to the formation of an easy diffusion path on the surface layer due to the ionic movements, enhanced intrinsic activity of the catalytic sites resulting from the higher crystallinity, high oxygen vacancies and a large electrochemically active surface area. The sole key parameter in achieving all the acquired characteristics is the annealing temperature. We believe that the straightforward method of bringing the desired combination of properties by just tweaking the annealing temperature is handy and energy-efficient, and hence easily adoptable.10aBi-functionality10aN-doped graphene10aOxygen Evolution Reaction10aoxygen reduction reaction10aperovskite10aSurface reconstruction1 aJhajharia, Suman, Kumari1 aGupta, Shashaank1 aManappadan, Zinoy1 aSelvaraj, Kaliaperumal1 aPadmanabhan, Myoor, K.1 aMahajan, Roop, L.  uhttps://library.ncl.res.in/content/surface-alteration-driven-bi-functional-catalytic-activity-alkali-niobate-n-doped-graphene