Figure 5. (A) Current−potential curves of WO3 and Bi2WO6 films under dark and light condition (scan rate of 0.02 V/s in 0.1 M H2SO4 aq. versus
Ag/AgCl, λ ≥ 420 nm). The horizontal dotted lines indicate the position of zero current. (B) UV−vis absorbance spectra and wavelength-dependent
photocurrent of the Bi2WO6 film (electrolyte, 0.1 M H2SO4; potential, 1.0 V versus Ag/AgCl; light source, 300 W Xe lamp with cutoff filters).