Hydrogen evolution reaction (HER) activity of conical Co–Fe alloy structures and their application as a sensitive and rapid sensor for H2O2 detection

In this work, the conical Co–Fe alloy structures were synthesized by two different methods: a two- and a one-step. The synthesis of nanoconical structures with regular, well-defined geometrical features, called the two-step method, requires using porous Anodic Alumina Oxide (AAO) templates. Contrary, any advanced pre-preparation of the substrate is not necessary for the one-step method. The fabrication of cones is carried out from the electrolyte containing an addition of a crystal modifier. Co and Fe are applied as electrodes in an alkaline environment. Their catalytic performance can be enhanced by modification of the shape and size of their structures, and in consequence, developing their active surface area. Many methods were used to analyze the coatings, such as Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray Spectroscopy (EDS), Energy-Dispersive X-ray Spectrometry (EDAX), X-ray Photoelectron Spectroscopy (XPS), and X-ray diffraction analysis (XRD). The catalytic properties of the coatings were recorded during the hydrogen evolution reaction and the reduction of the hydrogen peroxide and compared with the catalytic activity of bulk alloy. Nanocones produced in AAO templates were characterized by significantly higher catalytic activity and sensitivity in both reactions. However, they were unstable in the time of the experiment duration. Cones synthesized by the one-step method can be successfully applied as a catalyst and H2O2 detector.

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Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023)