Abstract:
In this study, copper (Cu) and nickel oxide (Ni2O3) microtubes (MTs) were synthesized using an electroless
template deposition technique within porous polycarbonate (PC) track-etched membranes (TeMs) to
obtain Cu@PC and Ni2O3@PC composite membranes, respectively. The pristine PC TeMs featured
nanochannels with a pore density of 4 × 107 pores per cm2 and an average pore diameter of 400 ±
13 nm. The synthesis of a mixed composite, combining Cu and Ni2O3 within the PC matrix, was achieved
through a two-step deposition process using a Ni2O3@PC template. An analysis of the resultant
composite structure (Cu/Ni2O3@PC) confirmed the existence of CuNi (97.3%) and CuO (2.7%) crystalline
phases. The synthesized catalysts were characterized by scanning electron microscopy (SEM), energy
dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) analysis, and atomic force microscopy (AFM).
In photodegradation assessments, the Cu/Ni2O3@PC mixed composite demonstrated higher
photocatalytic activity, achieving a substantial 59% degradation of norfloxacin (NOR) under UV light
irradiation. This performance surpassed that of both Ni2O3@PC and Cu@PC composites. The optimal pH
for maximum NOR removal from the aqueous solution was determined to be pH 5, with a reaction time
of 180 min. The degradation of NOR in the presence of these composites adhered to the Langmuir–
Hinshelwood mechanism and a pseudo-first order kinetic model. The reusability of the catalysts was also
investigated for 10 consecutive runs, without any activation or regeneration treatments. The Cu@PC
membrane catalyst demonstrated a marked decline in degradation efficiency after the 2nd test cycle,
ultimately catalyzing only 10% of NOR after the 10th cycle. In contrast, the Ni2O3@PC based catalyst
demonstrated a more stable NOR degradation efficiency throughout all 10 runs, with 27% NOR removal
observed during the final test. Remarkably, the catalytic performance of the Cu/Ni2O3@PC mixed
composite remained highly active even after being recycled 4 times. The degradation efficiency
exhibited a gradual reduction, with a 17% decrease after the 6th run and a cumulative 35% removal of
NOR achieved by the 10th cycle. Overall, the findings indicate that Cu/Ni2O3@PC mixed composite
membranes may represent an advancement in the quest to mitigate the adverse effects of antibiotic
pollution in aquatic environments and hold significant promise for sustainable water treatment practices
