HIGH EFFICIENT VISIBLE-LIGHT ACTIVATED PHOTO CATALYTIC SEMICONDUCTOR SnO2/Sn3O4 HETEROSTRUCTURE IN DIRECT BLUE 71 (DB71) DEGRADATION

Abstract

The SnO2/Sn3O4 were successfully prepared using a one-step hydrothermal method and exhibit the heterostructure formation. The heterostructure formation facilitates the enhancing of visible-light photoresponse of SnO2 which well known as the UV-light activated semiconductor. The heterostructure formation also exhibits high efficient photocatalytic performance by completely degrading 10 ppm of DB71 in 120 minutes after adding 50 mg of prepared-Tin oxide with a kinetic rate constant of 4.636 x 10 min. The kinetic constant rate of prepared-Tin oxide has 2.5 and 3 times faster compared to the kinetic constant rates of SnO2 and Sn3O4, respectively. The high efficient photocatalytic degradation was generated by the improvement of carrier mobilities through manipulating band alignment between SnO2 and Sn3O4 and prevented the recombination of photogenerated hole-electron which commonly generated in the intrinsic semiconductor. Heterostructure SnO2/Sn3O4 was not only forming high-efficiency photocatalytic degradation but also exhibiting blue shifting phenomenon. The UV-Vis adsorption response approaches were used to investigate and propose the photocatalytic degradation mechanism. After 120 minutes, there were only benzene adsorption peaks detected indicating the mineralization of DB71 dyes.