Fig. 2From: Synthesis of BiPO4/Bi2S3 Heterojunction with Enhanced Photocatalytic Activity under Visible-Light IrradiationThe XPS survey spectra of BB-2 (a) and high-resolution XPS spectra of Bi 4f (b), O 1 s (c), P 2p (d) and S 2p (e)Back to article page