In article number 1804372, Jr‐Hau He and co‐workers study the influences of the surface effect of 2D layered perovskites before and after mechanical exfoliation. The smooth 2D perovskite is less sensitive to ambient moisture and exhibits a considerably low dark current. This work reveals the strong dependence of the surface condition of 2D hybrid perovskite crystals on their moisture stability and optoelectronic properties.

Published in: "Advanced Materials".