Pd/BiOBr tetragonal platelets with controllable facets by the decoration of La dopant enabling highly efficient photocatalytic activity

Abstract

The charge transfer between semiconductors and metals is greatly dependent on the crystal structure and properties of the interface. It is well known that Schottky junctions formed by depositing Pd nanoparticles on BiOBr nanosheets can accelerate the transfer and separation of carriers. However, the stability of the crystal structure and the exposed crystal surface with high performance both decrease in the process of photo-deposition. In the present work, Pd/BiOBr photocatalysts decorated with an La dopant were fabricated by a two-step synthesis with solvothermal and photo-deposition methods. Interestingly, Pd/BiOBr crystals could be reconstructed by doping with La ions, such as the regrowth of facets with UV light irradiation. The instability of the crystal structure and lower photocatalytic performance could be reversed by doping with La ions. La-Doping refined the crystal structure and strengthened the charge transfer and separation of carriers over Pd/BiOBr, exhibiting enhanced photocatalytic activity toward the degradation of acid orange II (AO II). Moreover, the reason for the effects of the La ions was investigated by density functional theory calculations.