Cu–Pd Alloy Nanoparticles on Carbon Paper as a Self-Supporting Electrode for Glucose Sensing

Nanomaterials based on metals and their alloys have been paid increasing attention due to their adjustable morphology, high stability and excellent catalytic activity. In this work, Fritillaria cirrhosa-like Cu–Pd alloy nanoparticles were grown on carbon paper (Cu–Pd/CP) by one-step electrodeposition, serving as a self-supporting electrode to catalyze glucose oxidation. The morphological and structural characterizations of the Cu–Pd alloy were performed using scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results showed that Fritillaria cirrhosa-like Cu–Pd alloy nanoparticles with a size of about 600 nm were synthesized and uniformly distributed on CP. The 3D network structure composed of CP with good conductivity and Cu–Pd alloy nanoparticles with unique morphology greatly increased the specific surface area and conductivity of the material, which is beneficial to the electrocatalytic oxidation of glucose. As a self-supporting electrode, the prepared Cu–Pd/CP presented excellent electrocatalytic activity toward glucose oxidation with a wide linear range (0.003–10 mM), high sensitivity (2589 μA mM^–1 cm^–2), and low detection limit (1.3 μM). The proposed sensor has been successfully applied to the determination of glucose in real human serum samples, indicating that Cu–Pd/CP is a promising candidate for nonenzymatic glucose sensing.