A highly efficient visible light driven Fenton catalyst α-FeOOH/BiOI to degrade RhB

The heterogeneous photo-Fenton process is still inhabited by the poor recycling of Fe(III)/Fe(II). Therefore, a visible light active α-FeOOH/BiOI catalyst was prepared by facile precipitation method. The synthesized photocatalysts were characterized by different methods, such as XRD, SEM, HR-TEM, XPS. Results showed that the loose flocculent of α-FeOOH covered on the BiOI particle. Rhodamine B was selected to evaluate the photocatalytic performance under visible-light irradiation in the presence of H2O2. The superior photocatalytic activity of 0.5 M-FeOOH/BiOI was obtained that 100% of RhB can be degraded within 20 min illumination. UV–vis diffuse reflectance spectra and the photoluminescence measurements revealed that the 0.5 M-FeOOH/BiOI composite enhanced charge carrier separation in the way of Fe(III) consumed photo electron to form Fe(II). Simultaneously, the acceleration of Fe(III)/Fe(II) recycling is beneficial to catalyze H2O2 to form hydroxide radical (·OH). Photo stability further revealed that the 0.5 M-FeOOH/BiOI composite could be a promising material in wastewater treatment and other environmental remediation applications. α-FeOOH/BiOI photo-Fenton was prepared by a facile precipitation method. The Eg of BiOI and FeOOH is 1.76 and 1.18 eV respectively. The Eg band of 0.5 M-FeOOH/BiOI is lower than that of BiOI which facilitated the light absorption. According to the value of VB and CB of the FeOOH and BiOI, it can infer that photo electrons transferred to the CB of FeOOH from BiOI and holes flew to the VB of BiOI from FeOOH. Then the separation rate of charge carries on the BiOI is improved. Moreover, Fe(III) consumed the photoelectron and converted to Fe(II) which can catalyze H2O2 to form·OH. The main active species of the photo-Fenton process is·OH to degrade RhB. Moreover, h+ and·O2+- also played a weak role. [Display omitted] •A highly efficient α-FeOOH/BiOI photo-Fenton catalyst was synthesized.•20 mg/L RhB was completely degraded by 0.5 M-FeOOH/BiOI with 20 min visible light irradiation in the presence of H2O2.•The fast recycling of Fe(III)/Fe(II) facilitated to form ·OH.