Heterojunction construction with low band gap materials is an effective way of utilizing UV light active materials under visible light irradiation. Here, we report the synthesis of Bi 2 (O,S) 3 /Zn(O,S) heterostructure using simple solvothermal method without surfactant. The catalysts were investigated with different characterization techniques. All the composite catalysts showed high light absorption capacity in the whole visible light spectrum. The catalytic activity of the catalysts was evaluated by Cr(VI) reduction. While pure Zn(O,S) catalyst showed no significant Cr(VI) reduction, higher photocatalytic activity than individual components were exhibited after heterojunction construction with Bi 2 (O,S) 3 . 20-BiZnOS catalyst with Bi/Zn molar percentage of 20% showed the best photocatalytic activity among the composites with 99.5% Cr(VI) reduction within 12 min under visible light irradiation. Heterojunction formation between Bi 2 (O,S) 3 and Zn(O,S) nanoparticle, and selective adsorption of Cr(VI) and desorption of Cr(III) on the surface of 20-BiZnOS composite catalyst were ascribed to the enhanced photocatalytic activity of the composite catalyst.
Wastewater treatment becomes an important part to improve environmental quality and protect water resources. Thus, developing a new photocatalyst is a key solution for environmental issues. Herein, universal, highly efficient, and novel Bi 2 (O,S) 3 /Mo(O,S) 2 nanocomposite photocatalyst was fabricated by a facile method and the crystal structure, morphology, composition, and optical properties of the as-prepared catalysts were characterized in details. The photocatalytic performance of the catalysts was evaluated by the photodegradation of methyl orange (MO), rhodamine B (RhB), methylene blue (MB), and neutral red (NR), the results showed that 20% Bi-MoOS nanocomposite had excellent photodegradation activity towards all dyes. 96.0% of MO, 96.6% of RhB, 98.8% of MB and 91.3% of NR dyes were removed after 180 min, 40 min, 20 min, and 25 min visible light irradiation, respectively. The photodegradation of these dyes was further confirmed with HPLC. The excellent photocatalytic activity of the nanocomposites was due to the efficient separation and transport of photogenerated charge carriers induced by the fabricated binary heterostructures. The photodegradation fitted well the pseudo-first-order kinetics. The active species capture experiment study showed that, OH, O 2 − and h + all took parts in the degradation of dyes. The stability of the catalyst and reaction mechanism also explained in this work.