Polyaniline-supported MWCNTs/ZnO/Ag2CO3 composite with enhanced photocatalytic and antimicrobial applications

Abstract

A ternary system MWCNTs/ZnO/Ag₂CO₃ and its novel PANI-supported (MWCNTs = 150 mg) composite were prepared by precipitation and impregnation methods, respectively. The as-synthesized composites were characterized using different instrumentation techniques, including XRD, SEM-EDX, PL, and UV–Vis DRS spectroscopies. The photodegradation efficiency of the PANI-supported MWCNTs/ZnO/Ag₂CO₃ (MWCNTs = 150 mg) composite for the model Methyl Orange dye (MO) and industrial wastewater was examined and found to be 95.94 and 90.29 %, respectively. Using a PANI-supported composite, the effect of operational parameters such as pH = 4, initial dye concentration = 10 ppm, and catalyst dose = 150 mg/L on MO dye photodegradation was investigated. Under optimal conditions, the photodegradation performances of the bare ternary system and its PANI-supported composites were found to be 90.02 and 95.94 %, respectively. Different scavengers demonstrated that the major species actively involved in the degradation of MO dye were ^•O₂^– and ^•OH. During the photodegradation of MO using PANI-supported MWCNTS/ZnO/Ag₂CO₃ as a photocatalyst, the supper oxide (^•O₂^–) was found to be the predominant reactive species. The reusability of the supported photocatalyst was also investigated after five consecutive runs it was found that 49.78 % efficient and this revealed its substantial reusability. The antibacterial efficacy of the PANI-supported MWCNTs/ZnO/Ag₂CO₃ (at MWCNTs = 150 mg) against both gram-negative and gram-positive bacteria was found to be superior to those of the single, binary, and ternary systems.