Hierarchical Bi2O2CO3 microspheres with improved visible-light-driven photocatalytic activity

A high-efficiency Bi2O2CO3 photocatalyst was successfully synthesized using tri-sodium citrate as both the coordinating agent and carbon source through a hydrothermal process. Morphology modulation of the obtained products could be easily realized by tuning the concentration of tri-sodium citrate in sponge-like, rose-like and plate-like shapes. The as-prepared sponge-like Bi2O2CO3 microspheres, owning a narrowed band gap of 2.87 eV and a higher BET surface area of 43.99 m2 g−1, exhibit powerful visible-light-photocatalytic activity for the degradation of dyes under 300 W Xe lamp light irradiation. It is worthy to note that the optimal sponge-like Bi2O2CO3 microspheres also possess superior photocatalytic ability under natural sunlight.