Self-Cross-Linking Synthesis of CuO for dual-mode sensing of hydrogen peroxide

Hydrogen peroxide (H2O2) detection is crucial for both illness diagnosis and environmental monitoring. This paper reports on a sustainable strategy that involves ion exchange using copper ions and sodium alginate as chelating agents to synthesize CuO nanoflakes. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption-desorption curves were used to characterize the material. The catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to a blue-colored ox TMB in the presence of H2O2 demonstrated the peroxidase-like activities of CuO. Hydrogen peroxide was detected using a dual-mode sensing platform built on the basis of colorimetry and electrochemistry. The dual-mode sensing platform created can be analytically applied widely, and this work offers a green and ecologically friendly synthesis technique.