BackgroundNowadays, drugs have been developed widely for the remediation of different microbial diseases. However, the presence of these compounds have influence on the water bodies. Thereupon, the preparation of inexpensive and efficient catalysts for the antibiotics degradation is important for the treatment of toxic contaminant in water.MethodsThe ternary NiCo2O4-Bi2O3-Ag2ZrO3 nanocomposite has been presented through a facile co-precipitation methods. The as-prepared nanocomposites was studied for the decomposition of metronidazole (MTN) under the visible light, and characterized by different analysis such as TEM, UV-vis, XPS, SEM, FT-IR, EIS, ESR, BET, and PL techniques.Significant findingsThe determined band gap values of Ag2ZrO3, Bi2O3, NiCo2O4 and NiCo2O4-Bi2O3-Ag2ZrO3 nanocomposites were 2.67, 2.45, 2.18 and 1.92 eV, respectively. The degradation efficiency of NiCo2O4-Bi2O3-Ag2ZrO3 under visible light displays the 100.0% decomposition attained in 80 min. The important parameters such as neutral pH, 4.0 g/L of catalyst dosage, and 5 mg/L of MTN concentration were found to be favorable for this reaction. The great recyclability attributes of the prepared catalyst were discerned after five successive cycles. The toxicity of the degraded MTN products were harmless and non-toxic. The scavenging test revealed that ·OH and ·O2− were the important radicals in the degradation of MTN by NiCo2O4-Bi2O3-Ag2ZrO3. The fabricated NiCo2O4-Bi2O3-Ag2ZrO3 was also investigated for the antimicrobial activity.