Preparation of Bi 3.64 Mo 0.36 O 6.55 by reflux method and its application in photodegradation of organic pollution

Bismuth molybdate (γ-Bi 2 MoO 6 ) photocatalyst has garnered huge attention in the field of photocatalysis because of its band gap (2.5–2.8 eV) and good visible-light response (420 ≤ λ ≤ 500 nm). However, as a kind of bismuth molybdates, there are only few studies on Bi 3.64 Mo 0.36 O 6.55 (BMO), thus further exploration is needed. Herein, a simple reflux method was developed to synthesize the cubic phase of BMO. This method is simple and easy to operate under atmospheric pressure, showing great potential for large-scale production. In contrast with the nanosheet structure of Bi 2 MoO 6 , the morphology of BMO is a mixture of nanorod and nanoparticle-like structure. The band structures showed that the band gap, conduction band position and the valence band position of BMO was 2.77 eV, − 0.33 eV and 2.44 eV, respectively. A new mixed phase of 3Bi 2 O 3 ·2MoO 3 appeared in BMO crystal, showing that the phase transition of BMO began at 400 °C. When BMO was calcined at 300 °C, photocatalytic degradation rate was up to maximum. The photocatalytic activity of visible-light range was tested and compared with γ-Bi 2 MoO 6 . BMO had better photodegradation activity than that of the Aurivillius phase γ-Bi 2 MoO 6 due to its larger band gap and strong oxidation ability.