Pt Nanoparticle-Decorated Se Rods for Electrochemical Detection of 17β-Estradiol and Methanol Oxidation

Fabricating platinum (Pt) nanoparticle-draped selenium (Se) rods over the spacious region of glassy carbon electrodes could stimulate an impressive electrocatalytic activity owing to the synergic effect and interfacial property between Pt and Se, the oxophilic property and the anchoring effect of Se, the electron confinement effect, and the surface-to-volume ratio possessed by Pt. Examination of the structure and morphology highlights the physical and chemical properties of the Pt/Se catalyst, as revealed by different physicochemical characterization techniques. From these characterizations, we identified a dual-functional electrocatalyst Pt/Se for electrochemical detection of 17β-estradiol (E₂) and methanol oxidation. When used for the electrochemical detection of estradiol, the Pt/Se catalyst displays an excellent response toward electro-oxidation of estradiol in the linear sweep voltammetry (LSV) and the amperometry-it technique. The proposed sensor utilizes a concentration range that varies from 0.05 to 85.5 μM with good sensitivity (0.0376 mA μM^-1cm^-2), a lower limit of detection (LOD) being 11.12 nmol L^-1, and the limit of quantitation (LOQ) being 36.06 nmol L^-1. It yields lower detection limits (LODs: 13.17 and 17.04 nmol L^-1) even on detecting estradiol in environmental water samples (river and tap water samples) at a buffered pH of 7.0. In the methanol oxidation reaction (MOR), the Pt/Se catalyst displays a good mass activity and turnover number (TON) of 2.37 A/mg and 1.36 s^-1, respectively, by cyclic voltammetry and chronoamperometry. As a result, the prepared Pt/Se electrocatalyst, has provided a creditable combination of stability, electron transfer rate, conductivity, and dual applicability to the electrochemical sensor and the methanol oxidation fuel cell for the first time.