Experimental and computational study of Bi2O3/WO3 heterostructures as efficient solar driven photocatalyst

Pure Bi 2 O 3 degraded 58.7 % of MB in 240 min. However, Bi 2 O 3 /WO 3 nanocomposite achieved 81.8 % degradation in the same time. • Bi 2 O 3 /WO 3 nanocomposite synthesized successfully by co-precipitation method. • Formation of nanocomposite was verified through XRD and SEM results. • WO 3 addition tuned the band gap of Bi 2 O 3 . • Bi 2 O 3 /WO 3 is an effective nanocomposite for the degradation of MB under solar light irradiation. Industrial wastewater is always a matter of challenge, polluting the environment and ultimately causing a hazardous effect on human beings and various other species. For the elimination of these pollutants, in this study, we synthesized Bi 2 O 3 nanoparticles and Bi 2 O 3 /WO 3 heterostructures by chemical co-precipitation method and investigated their photocatalytic activity for the degradation of methylene blue (MB) under solar light irradiation. The synthesized nanoparticles were characterized by various analytical techniques, including X-ray diffraction (XRD), Scanning-electron-microscopy (SEM), Fourier-Transform-Infrared Spectroscopy (FTIR), and UV–Vis. absorption Spectroscopy. Results of this study revealed that the pure Bi 2 O 3 sample has a band gap of 3.5 eV, however, Bi 2 O 3 /WO 3 heterostructure exhibited a reduction in band gap to 3.1 eV. The decrease in band gap significantly enhanced absorption of solar light, which correlated with an increase in photocatalytic activity as Bi 2 O 3 /WO 3 nanocomposite degraded 81.5 % of MB in 240 min, while pristine Bi 2 O 3 only degraded 58.7 % of the MB in the same period. The enhanced photocatalytic performance of the nanocomposite can be attributed to the synergistic action between Bi 2 O 3 and WO 3 , which enhances the production of reactive oxygen species (ROSs) and the efficiency of charge separation, thus promoting the degradation of MB. A type-II heterostructure has been proposed to enhance the separation of charge carriers. Moreover, our computational study supported these findings, indicating a decrease in trends of the band gap of heterostructure as compared to pristine Bi 2 O 3 . The results of this study highlight the potential of Bi 2 O 3 /WO 3 nanocomposites as promising materials for environmental remediation applications, particularly for the efficient removal of organic pollutants from wastewater under solar irradiation.