Co₃O₄ decorated undoped and doped reduced graphene-oxide nanocomposites for effective degradation studies of amoxicillin antibiotic

In the present study, undoped and doped reduced graphene oxide-based metal nanocomposites were prepared using the leaves extract of Morus alba (Mellburry). Prepared materials were employed for degradation studies of amoxicillin (AMX). Different techniques such as UV Vis, FTIR, XRD, SEM, EDX, TGA and DTA were employed to characterize these composites. In UV–Visible spectroscopy, undoped and doped composites showed absorption peaks at 260, 273 and 323 nm. Co₃O₄/rGO and Co₃O₄/NrGO depicted crystallite sizes of 9 and 7 nm, respectively. While TGA/DTA data illustrated that Co₃O₄/NrGO is thermally more stable than Co₃O₄/rGO. Point of zero charge is calculated to be 7.1 and 7.2 for Co₃O₄/rGO and Co₃O₄/NrGO. The effect of operational parameters (amount of catalyst, temperature, pH, and concentration of analyte) on the degradation of AMX has been investigated. Both depicted optimum response with 5 mg/L analyte concentration at 45 °C under basic conditions with 2 mg (Co₃O₄/NrGO) and 4 mg (Co₃O₄/rGO) catalyst amount. Comparative studies showed that Co₃O₄/NrGO exhibited greater degradation efficiency (90 %) than Co₃O₄/rGO (85 %) under optimum conditions. Thermodynamic studies revealed that the degradation of AMX by Co₃O₄/rGO and Co₃O₄/NrGO was a spontaneous and endothermic process. Langmuir adsorption isotherm applied to both cases. In addition to regeneration studies, mechanisms related to nanocomposite synthesis and antibiotic degradation were also studied. These findings supported prepared composites as promising materials for sequestration studies of amoxicillin.