The preparation of NiCo2O4 nanoboulders and their application in the electrochemical detection of ofloxacin drug

Abstract

A sensitive electroactive platform relies directly upon the efficient and conductive interface. This work offers a simple and effective method for synthesizing NiCo2O4 using CTAB surfactant, suited for trace-level antibiotic detection. The route realized the controlled growth of tiny NiCo2O4 nanoboulders with an exposed interface. A comparative evaluation of the bimetallic nanostructures with their pristine compositional counterparts, i.e., NiO and Co3O4, supports its superior electrochemical characteristics based on the synergism of strong redox activity and conductivity from the bimetallic components. The NiCo2O4 nanoboulders exhibited strong electrochemical activity when configured as electrode material for detecting ofloxacin (OFL), a common antibiotic. The sensor exhibited excellent working linearity in a low-concentration range of 0.01–5 ​μM with a detection limit of 1 ​× ​10−3 ​μM for OFL. The kinetics of the NiCo2O4 further supported the electrocatalytic oxidation of OFL to be diffusion controlled with an estimated diffusion coefficient of 2.03310−6 ​cm2 ​s−1. Moreover, the constructed sensor is applicable for detecting OFL from environmental samples, reflecting its workability in complex real-environment.

Keywords

• NiCo2O4
• Ternary metal oxides
• Ofloxacin
• Emerging pollutants
• Electrochemical sensors