Anchoring modified g-C3N4 with Bi5O7Br: S-scheme photocatalysts with boosted activities in elimination of inorganic and organic pollutants

In this research, modified g-C3N4 with hydrogen peroxide was decorated with Bi5O7Br nanoparticles (abbreviated as g-C3N4(M)/Bi5O7Br) via a facile precipitation procedure. The s-scheme g-C3N4(M)/Bi5O7Br (20 %) nanocomposite showed superior photocatalytic ability in degradation to tetracycline (TC), as a pharmaceutical pollutant, upon visible light. The maximal removal constant was 34.3 and 6.83-folds premier than g-C3N4 and g-C3N4 (M) systems, respectively. Interestingly, the g-C3N4(M)/Bi5O7Br (20 %) nanocomposite demonstrated excellent activity in visible-light elimination of amoxicillin (AMX) (an antibiotic), methyl orange (an anionic pollutant), rhodamine B and Fuchsine (cationic pollutants), and also photoconversion of Cr (VI) into Cr (III) upon visible light, that was about 15.5, 18.9, 22.4, 21.7, and 23.2-folds preferable than that of g-C3N4, respectively. The spectrophotometric, photoluminescence, and electrochemical studies approved the production of more charges upon visible light, and promoted segregation/movement of the generated charges within the binary g-C3N4(M)/Bi5O7Br (20 %) photocatalyst. The impressive segregation of charges was assigned to developing an s-scheme structure between Bi5O7Br and g-C3N4 (M) semiconductors. Scavenging tests revealed that superoxide anion radicals, holes, and hydroxide radicals were crucial species in the reactions. Eventually, the biocompatibility of the treated solution was confirmed via the successful growth of wheat seeds. In conclusion, the s-scheme g-C3N4(M)/Bi5O7Br system can be used as a suitable sample for environmental detoxification.