Enhanced Photocatalytic Performance of Z-Scheme Design of Bi2O2CO3/Ag/g-C3N4 Photocatalyst

The g-C3N4/Ag/Bi2O2CO3 nanosheets were synthesized using a mixture of precursors containing melamine and nitrates of silver and bismuth through a simple one-pot synthesis strategy. In the presence of ammonium nitrate, g-C3N4/Ag/Bi2O2CO3 composite catalysts with different silver mass ratios were prepared, and the photodegradation performance of the composite samples was evaluated by photodegradation of tetracycline hydrochloride (TC) under simulated solar light irradiation. The synthesized composites were characterized by XPD, XPS, FT-IR, TEM, UV-vis DRS and PL. It was found that the g-C3N4/Ag/Bi2O2CO3 catalyst with Ag mass ratio of 4% exhibited the highest catalytic activity, and the degradation effect was more than 9 times that of pure C3N4 and nearly 5 times that of g-C3N4/Bi2O2CO3.In addition, cyclic experiments showed that g-C3N4/Ag/Bi2O2CO3 composites had certain stability. The photocatalytic performance of the g-C3N4/Ag/Bi2O2CO3 composites was attributable to the heterogeneous junction of Bi2O2CO3 and g-C3N4 and the surface plasmon resonance effect (SPR) of Ag nanoparticles. The energy levels of Bi2O2CO3 and g-C3N4 were properly matched to form a heterojunction, which promoted the separation and transfer of photogenerated electrons and holes, thereby improving the photocatalytic performance. The Ag surface plasmon resonance (SPR) effect not only accelerated the separation and transmission of electron-hole pairs, but also enhanced the absorption of visible light. Finally, based on the above basis, a possible photocatalytic mechanism was proposed. [GRAPHICS]

Automated summary

In this study, g-C3N4/Ag/Bi2O2CO3 nanosheets were successfully synthesized using a one-pot synthesis strategy and evaluated for their catalytic performance in the photodegradation of tetracycline hydrochloride. The g-C3N4/Ag/Bi2O2CO3 catalyst with 4% Ag mass ratio exhibited the highest catalytic activity. The photocatalytic performance of the composite material was attributed to the heterogeneous junction of Bi2O2CO3 and g-C3N4, as well as the surface plasmon resonance effect of Ag nanoparticles.