A novel Bi-based oxychloride CdBiO2Cl: Crystal structure, electronic structure and photocatalytic activity

CdBiO2Cl with layered structure as a novel efficient photocatalyst was synthesized by a solid state reaction method. The optical band gap of CdBiO2Cl is determined to be 3.08 eV by UV–vis diffuse reflectance spectroscopy. The photocatalytic activity of CdBiO2Cl for degrading methyl orange (MO) is much higher than that of commercially obtained anatase TiO2 under UV light illumination. The Ag-loading over CdBiO2Cl leads to an obvious increase in the photocatalytic performance. The photocatalytic activity is discussed in close connection with the crystal structure and the electronic structure.

Research highlights▶ In light of energy shortages and environment crises, semiconductor-photochemistry has attracted ever-growing research interest during the past decades. Owing to their unique layered structures and high chemical stabilities, Bi-based oxychlorides have found potential application as efficient photocatalysts. The layer structure-induced permanent electric fields facilitie the separation of electron–hole pairs. If the unique layer structure and a hybrid state in conduction band (CB) and/or valence band (VB) can be combined in one semiconductor, the photocatalysis efficiency will be greatly further promoted due to the fair mobility resulted from the strong band dispersion. Here, based on density functional theory (DFT) calculation, CdBiO2Cl, as a case in point of this semiconductor, was for the first time investigated as a novel photocatalyst with high performance. This study not only sheds some light on the deliberate synthesis of other oxychloride functional materials, but also discloses insights into developing efficient photocatalysts with synergistic features. We believe this work is timely in view of the current interest in solar energy and green chemistry.