Enhanced photocatalytic performance of boron doped Bi2WO6 nanosheets under simulated solar light irradiation

Abstract Bi 2 WO 6 doped with different amounts of boron atoms (0.1, 0.5, 1.0, 5.0 and 10% B) were synthesized using hydrothermal method and their photocatalytic activities to degrade rhodamine B (RhB) under simulated solar light was investigated. The successful incorporation of B atoms in Bi 2 WO 6 was proved by FT-IR, Raman spectra and XPS. Doping with B could affect the pore structure and volume. 0.5% B/Bi 2 WO 6 displayed more mesopores with higher total pore volume than pure Bi 2 WO 6 ; while the pores of 10% B/Bi 2 WO 6 mainly distributed in microporous range with much less total pore volume. As a result, 0.5% B/Bi 2 WO 6 displayed stronger adsorption capacity to RhB, favoring the photodegradation. In addition, the doped B atoms could act as electron traps and facilitate the separation of photogenerated electron–hole pairs due to its electron deficient and oxytropic characteristics. 0.5% B/Bi 2 WO 6 displayed the highest photocatalytic activity under simulated solar light with rate constant ( k obs ) 8.8 times of that using pure Bi 2 WO 6 . Its photoactivity was affected by solution pH and the optimum was achieved at pH 7. At this condition, around 100% of RhB (10 −5  mol/L) was degraded in 180 min. The photogenerated holes were the main active species responsible for the photodegradation of RhB by B/Bi 2 WO 6 .