Biosynthesis of plasmonic Ag/Bi2O2CO3 nanocomposites from Acacia hybrid leaf extract with enhanced photocatalytic activity

A series of plasmonic Ag/Bi2O2CO3 photocatalytic nanocomposites was biosynthesized readily by a facile, green procedure at hydrothermal temperature as low as 65 degrees C from Bi(NO3)3, Na2CO3, AgNO3, and ethanolic Acacia hybrid leaf extract. The results showed that, by using Acacia hybrid leaf extract as a novel silver reduction agent, the spherical-like Ag nanoparticles crystallized in a rarely-found hexagonal phase with grain sizes from 6 to 15 nm. These nanoparticles exhibiting a surface plasmon resonance (SPR) effect in a broad visible light region from 400 to 800 nm were loaded on the surface of Bi2O2CO3 nanosheets to form Ag/Bi2O2CO3 nanocomposite. The methylene blue photogradation efficiency of the optimized nanocomposite (84 %) is significantly superior to that of pure Bi2O2CO3 (22 %) after 5 h of visible light irradiation. The enhanced visible light absorption arising from the SPR effect induced by plasmonic Ag nanoparticles and a heterojunction formed between Bi2O2CO3 nanosheets and these nanoparticles were supposed to be main reasons for the great enhancement in photocatalytic activity of Ag/Bi2O2CO3 nanocomposite.

Automated summary

A series of plasmonic Ag/Bi2O2CO3 photocatalytic nanocomposites were easily synthesized using Acacia hybrid leaf extract as a silver reduction agent, resulting in spherical Ag nanoparticles on the surface of Bi2O2CO3 nanosheets. The optimized nanocomposite exhibited significantly enhanced photocatalytic activity for methylene blue degradation under visible light due to the surface plasmon resonance effect and heterojunction formation.