A Initiative Intercalating Strategy for Conversion of Bi ₂ O ₃ to Bi ₂ O ₂ [BO ₂ (OH)] and Double Internal Electric Field‐Dependent Photoelectrochemistry Properties

Herein, we, for the first time, have developed a facile anion intercalation method to prepare uniform Bi 2 O 2 [BO 2 (OH)]/Bi 2 O 3 and Bi 2 O 2 [BO 2 (OH)] nanosheets, in which H 2 O 2 is employed as the exfoliating reagent to break the weak Bi−O bonds (2.572 Å) between [Bi 2 O 2 ] n 2n+ layers, then allowing borate ion to precisely intercalate into [Bi 2 O 2 ] n 2n+ layers. Further, density functional theory (DFT) calculations reveal that both O 2p and B 2p of [BO 3 ] 3− layer obviously contribute to an downshift of valence band (VB) and upshift of conduction band (CB), leading to a wider band gap of Bi 2 O 2 [BO 2 (OH)]. Thus, Bi 2 O 2 [BO 2 (OH)]/Bi 2 O 3 exhibit a higher photocatalytic activity than Bi 2 O 3 for the degradations of rhodamine B (RhB) under ultraviolet light irradiation (λ < 420 nm), which may be resultant from a synergetic effect of double internal electronic field that has improved charge separation efficiency. For featured layered materials, anion intercalation is an artful facile strategy to develop new, efficient photocatalysts.