Fig. 4From: Determining the Catalytic Activity of Transition Metal-Doped TiO2 Nanoparticles Using Surface Spectroscopic Analysis a Valence spectra and b magnified view of valence band edge of anatase TiO2 and the five TM-TiO2. c The plot of valence band maximum values of TiO2 and the five TM-TiO2 Back to article page