Fig. 2
From: Impact of grain boundaries on efficiency and stability of organic-inorganic trihalide perovskites
Nanoscale photoconductivity imaging on MAPbI3. a AFM (top) and MIM-Im/Re images (inside the black dashed rectangles in the AFM data) when the 532-nm laser is turned off (middle) and on (bottom) for the 18% PCE sample. The same results for the 15% PCE sample are shown in b. The scale bars in a and b are 1 μm
