Figure 7. Cyclic voltammetries of MIS photoanodes with various interfacial layers and metal overlayers and their corresponding Mott–Schottky plots.

(a) Representative j–V behaviour of the n-Si/SiO_x,RCA/Al₂O₃/Pt (2 nm)/Ni (4 nm) and n-Si/SiO_x,RCA/Al₂O₃/Ni (6 nm). For comparison, the samples without Al₂O₃ are also shown; with the SiO_x,RCA and SiO_x,native. (b) Mott–Schottky plots of n-Si/SiO_x,RCA/Al₂O₃/Pt (2 nm)/Ni (4 nm) and n-Si/SiO_x,RCA/Al₂O₃/Ni (6 nm). (c) Mott–Schottky plots of n-Si/SiO_x,RCA/Pt/Ni and n-Si/SiO_x,native/Pt/Ni. All the plots shown are samples measured after 18 h of ageing treatment in 1 M KOH solution.