Fig. 10

XPS spectrum of Ti 2p3/2 for as-fabricated state (A0.A90) and hot isostatic pressure state (B0,B90) at sputtering depth of 0 nm, 2 nm, 6 nm, and 10 nm of passive film, which were promoted potentiostatically at 0.6 V_SCE for 1800s in artificial saliva solution at 37 °C.