Synthesis of ternary heterostructured rice-stick-like Ag/polyoxometalates/nitrogen-doped carbon nanotube hybrids for the sensitive detection of adrenaline

This study presents the innovative design and synthesis of rice-stick-like Ag/polyoxometalates/nitrogen-doped carbon nanotubes (Ag/POM/N-CNTs) using an efficient and mild reduction method. N-CNTs are first synthesized through a self-degrading template method followed by the carbonization of polypyrrole nanotubes (PPy-NTs). The N-CNTs exhibit excellent characteristics, including a high length-to-diameter ratio and an interconnected nanotube structure, which shorten the electron transport distance and enhance electrochemical properties. During the process of loading Ag nanoparticles (Ag NPs) onto the N-CNTs, POM serves as both a reducing and linking agent. The synergistic effect between Ag species and N-CNTs significantly improves the catalytic performance of the nanohybrids. As a result, the Ag/POM/N-CNT-based electrochemical sensor demonstrates exceptional performance in adrenaline detection, with a broad linear range (0.40–700 μM), a low detection limit (0.30 μM, S/N = 3), and a sensitivity of 3.13 μA μM −1 . In addition to these advantages, the composite material also exhibits excellent specificity and stability, strongly indicating the practical application potential of Ag/POM/N-CNTs in adrenaline detection.