Synthesis of Ag-doped ZIF-8 photocatalyst with excellent performance for dye degradation and antibacterial activity

Abstract

Doping of metal-organic frameworks (MOFs) with active agents is highly desirable, as it can lead to increased photocatalytic efficiency, compared to the bare framework. Herein, Ag-X@ZIF-8 catalysts with different Ag content are successfully synthesized using a fast and facile method. The prepared materials are primarily characterized by different techniques such as FT-IR, PXRD, SEM/EDS, TEM, UV-DRS, EIS and BET analysis. Then, their application as: (a) photo-catalysts for degradation of Rhodamin B (RhB) and methyl orange (MO) as the dye models; (b) antibacterial agents; are studied. Among the synthesized catalysts, Ag-15 %@ZIF-8 shows the best photo-catalytic performance under visible light irradiation. Using this catalyst, after 30 min, the conversion of MO and RhB, are measured to be 100 % and 93 % respectively. The first order kinetic model is implemented to study the kinetic of dye degradation. The stability tests show that our synthesized photo-catalyst can maintain its activity after four cycles. Trapping studies indicated that hydroxyl radicals (OH) and photo-generated holes (h+) were the main active species in photocatalytic degradation of both dyes. In addition to the enhanced photo-catalytic property, the Ag doped ZIF-8 shows improved antibacterial activities against both Gram-positive and Gram-negative bacteria. Overall, the proposed material in this work seems to be a reusable and economical photocatalyst for water purification and disinfection.