Figure 1

XPS survey spectra of the perovskite films documented for (a) fresh samples (taken after 25 hrs of sample preparation) and after the aging of (b) 500 hrs and (c) 1000 hrs, in open air under the room temperature. The graph (d) shows a comparison of the concentrations (in atomic %) of C, N, O, Ti, In and Sn between fresh and aged (1000 hrs) perovskite layer.