BiOCl Atomic Layers with Electrons Enriched Active Sites Exposed for Efficient Photocatalytic CO2 Overall Splitting

BiOCl atomic layers (BOCNSs-i) were prepared by exfoliating hydrothermally synthesized BiOCl (BOCNSs) via ultrasonication in isopropanol for efficient photocatalytic CO 2 overall splitting to CO and O 2 . The obtained BOCNSs-i photocatalyst exhibits a distinctly improved photocatalytic performance to stoichiometrically produce CO and O 2 at the ratio of 2:1, with the CO evolution rate reaching 134.8 µmol g −1  h −1 under simulated solar light (1.7 suns) and reaching 13.3 mmol g −1  h −1 under concentrated solar irradiation (34 suns). With the thickness of BiOCl photocatalyst reducing to atomic layers, the charge carrier transfer and separation were enhanced by shortened transfer distance and the increased built-in electric field intensity, and electrons enriched Bi sites were exposed for activating CO 2 molecules.