Hierarchical Gadolinium Oxide Microspheres for Enzymeless Electro-biosensors in Hydrogen Peroxide Dynamic Detection

A porous gadolinium oxide spherically hierarchical structure (Gd₂O₃-ms) has been developed by using a hydrothermal method to perform enzymeless dynamic detection of hydrogen peroxide (H₂O₂), based on its high sensitivity in electrocatalytic reduction of H₂O₂. X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy have assisted in shedding light on the morphology, material formation process, structure, and properties of the porous gadolinium oxide microspheres. The linear range from 1 to 450 μM (linear correlation coefficient 0.991), sensitivity of 13.9 μA mM⁻¹, and fine detection limit with a prompt current response attaining stable value were achieved by this enzymeless sensor, which was also employed to implement the dynamic tracing of H₂O₂-releasing processes.