MBiO2Cl (M Sr, Ba) as novel photocatalysts: Synthesis, optical property and photocatalytic activity

Novel quaternary photocatalysts MBiO{sub 2}Cl (M=Sr, Ba) have been successfully developed for efficient photodecomposition of RhB. Their photocatalytic mechanism was also investigated. - Highlights: • Two Bi-based compounds SrBiO{sub 2}Cl and BaBiO{sub 2}Cl were explored as photocatalysts. • They were successfully synthesized by a solid-state reaction. • RhB can be effectively photodecomposed by SrBiO{sub 2}Cl and BaBiO{sub 2}Cl under UV light. • ·OH radicals serving as active species play important roles in degradation process. - Abstract: Two Bi-based compounds SrBiO{sub 2}Cl and BaBiO{sub 2}Cl were successfully synthesized by a solid-state reaction and investigated as new photocatalysts for the first time. Their microstructures and optical properties were characterized by XRD, SEM and DRS. The band gaps of SrBiO{sub 2}Cl and BaBiO{sub 2}Cl were separately determined to be 3.52 and 3.71 eV, and their E{sub CB} and E{sub VB} were also estimated. The photocatalytic activities of the as-prepared samples were evaluated by photodecomposition of rhodamine B (RhB) in aqueous solution. The results revealed that both SrBiO{sub 2}Cl and BaBiO{sub 2}Cl can be used as effective photocatalysts under UV irradiation, and SrBiO{sub 2}Cl exhibits a higher photocatalytic activity than BaBiO{sub 2}Cl, which was also verified by the PL spectra. Terephthalic acid photoluminescence probingmore » technique (TA-PL) demonstrated that ·OH radicals serving as active species play an important role in photooxidative degradation of RhB over SrBiO{sub 2}Cl and BaBiO{sub 2}Cl. Moreover, a larger amount of ·OH radicals generation was observed over SrBiO{sub 2}Cl, which is in agreement with its higher photocatalytic activity.« less