Reinforcing 2D Single-Crystal Bi₂O₂CO₃ with Additional Interlayer Carbonates by CO₂-Assisted Solid-to-Solid Phase...

A facile gaseous CO₂ mediated solid-to-solid transformation principle is adopted to insert additional CO₃ ^2- anions into the thin single-crystal nanosheets of Bi₂O₂CO₃, which is built of periodic arrays of intrinsic CO₃ ^2- anions and (Bi₂O₂)²⁺ layers. The additional CO₃ ^2- anions create abundant defects. The Bi₂O₂CO₃ nanosheets with rich interlayer CO₃ ^2- exhibit superior electronic properties and charge transfer kinetics than the pristine single-crystal 2D Bi₂O₂CO₃ and display enhanced catalytic activity in photocatalytic CO₂ reduction reaction and the photocatalytic oxidative degradation of organic pollutants. This work thus illustrates interlayer engineering as a flexible means to build layered 2D materials with excellent properties.