Study on photocatalytic degradation of formaldehyde and rhodamine b by BiOI@Carbon sphere core–shell nanostructures composite photocatalyst

In this paper, a simple hydrothermal and solvothermal method was used to prepare BiOI@Carbon sphere (BC-x) composite photocatalyst. The photocatalytic performance of BiOI@Carbon sphere on HCHO degradation was studied by controlling amount of carbon sphere. The photocatalytic performance of BiOI@Carbon sphere is significantly improved than that of BiOI. Under visible light irradiation, the degradation rate of HCHO by BC-3 reached 73 % within 40 min and the degradation rate of RhB reached 86 % within 60 min. The improved photocatalytic efficiency of BiOI@Carbon sphere is due to the synergistic effect of interfacial contact and acceleration of photo generated carrier transport and separation by using carbon sphere as an efficient electron transfer medium. Free radical capture confirms the charge transfer mechanism and proves that •O2– and h+ are active substances in the oxidation reaction of formaldehyde.