In Situ Synthesis of Bi2O3 Nanoparticles on ZincMe (Me=Al or Cr) Layered Double Hydroxide Frameworks for Photocatalytic Oxygen Evolution from Water under Solar‐Light Activation

Abstract A key target to boost solar‐to‐chemical conversion processes is to fabricate an efficient solar‐light‐responsive photocatalyst. Herein, we report the in situ synthesis of nanoparticles (NPs) of Bi 2 O 3 directly on Zn‐based layered double hydroxide (LDHs) frameworks. The in situ synthesis of Bi 2 O 3 NPs is done at room temperature, is ligand free and explores the ability of calcined Zn Me LDHs to reconstruct their layered structures in Bi(NO 3 ) 3 aqueous solution. The in situ formation of Bi 2 O 3 NPs on Zn Me LDHs is assessed by transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), powder X‐ray diffraction (XRD), and UV/Vis spectroscopy and compared with the features of a corresponding Bi 2 O 3 NPs/LDH prepared by the conventional impregnation route. The rapid photocatalytic response of the Bi 2 O 3 NPs/Zn Me LDH ( Me =Al, Cr) heterostructures is confirmed by O 2 generation from water under solar‐light irradiation. The rate of O 2 generation increases by a factor of approximately 2 for the ZnCrLDH based catalysts as compared to that of the family of ZnAlLDH catalysts. Further, the presence of the bismuth phase and its nano‐dimension leads to increased efficiency for the in situ prepared Bi 2 O 3 NPs/LDHs as compared to that of impregnated Bi 2 O 3 /LDH and the pristine LDHs.