The electrochemical sensor for methanol detection based on trimetallic PtAuAg nanotubes

Methanol has attracted broad interests for decades due to its application in various aspects of society, such as the fuel cell and the qualification of alcoholic beverages. Based on Ag nanorods (Ag NRs) prepared by hydrothermal method, PtAuAg nanotubes were obtained through galvanic replacement reaction at 75 °C. Various techniques including scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectrometer and energy-dispersive X-ray spectroscopy were used to characterize the morphology, structure and elemental composition of the NTs. The trimetallic noble metal composition enhanced the poison tolerance of Pt against CO-like intermediates in the process of methanol oxidation. The constructed methanol sensor displayed remarkable catalytic ability toward electrochemical methanol oxidation, offering a good linearity within 0.05–1.8 mM, a high sensitivity of 24.3 mA mM⁻¹ cm⁻² and a low detection potential of − 0.2 V. Furthermore, its excellent selectivity and stability revealed great potentials of the methanol sensor in alcoholic beverages evaluation, biological fuel cells and medical industries.