Fig. 4

Microscopy structure investigation of NLMO-Zn. a Bright-field TEM image of the particle along the [010] projection. Inset shows the selected area diffraction pattern from the particle. b HAADF-STEM image of NLMO-Zn. c Simulated HAADF images in the [010] projection of the three cases: undoped NLMO, 5%-Zn occupying the Na site in NLMO-Zn, and 5%-Zn occupying the Mn site in NLMO-Zn. d Simulated HAADF images showing the different contrasts by the variation of Zn-occupancy (3%, 5%, 7%, and 9% Zn in the Na layer)