Facile Synthesis, Characterization, and Photocatalytic Evaluation of In 2 O 3 /SnO 2 Microsphere Photocatalyst for Efficient Degradation of Rhodamine B.

The tin dioxide (SnO 2 ) photocatalyst has a broad application prospect in the degradation of toxic organic pollutants. In this study, micron-sized spherical SnO 2 and flower indium oxide (In 2 O 3 ) structures were prepared by a simple hydrothermal method, and the In 2 O 3 /SnO 2 composite samples were prepared by a "two-step method". Using Rhodamine B (RhB) as a model organic pollutant, the photocatalytic performance of the In 2 O 3 /SnO 2 composites was studied. The photocurrent density of 1.0 wt.% In 2 O 3 /SnO 2 was twice that of pure SnO 2 or In 2 O 3 , and the degradation rate was as high as 97% after 240 min irradiation (87% after 120 min irradiation). The reaction rate was five times that of SnO 2 and nine times that of In 2 O 3 . Combined with the trapping experiment, the transient photocurrent response, and the corresponding characterization of active substances, the possible degradation mechanism was that the addition of In 2 O 3 inhibited the efficiency of electron-hole pair recombination, accelerated the electron transfer and enhanced the photocatalytic activity.