Self-assembled micelle-based polypyrrole nanotube-incorporated copper oxide nanocomposite for the optical, structural and electrochemical detection of hydroquinone in water samples and HER application

Recently, hydrogen has garnered significant attention as a renewable and environmentally friendly energy source. The majority of industrial hydrogen is produced by turning natural gas into hydrogen. In this case, the development of reliable, economical, and effective catalysts that can produce hydrogen from water with minimum electrical bias is one of the main objectives of large-scale electrolysis. One approach to achieving the practical application of electrocatalysts in the production of hydrogen is to use easily accessible electrocatalyst materials that can facilitate the oxidation of water. In this work, we report the synthesis of an electrocatalyst for the electrochemical detection of the hydroquinone (HQ) analyte molecule in water samples and H₂ production. A polypyrrole nanotube/copper oxide (PNT/CuO) nanocomposite was synthesized <i>via</i> the self-assembly of a soft template obtained through chemical polymerization and a one-pot hydrothermal method. The prepared material was characterized using various techniques to examine its crystal phase, functional groups, and surface morphology. An electrochemical study was conducted using a PNT glassy carbon electrode (GCE) and PNT/CuO GCE, and CV curves showed a large surface area with good oxidation behaviour towards the HQ analyte. The DPV analysis of the HQ analyte exhibited an LOD of 0.36 μM and a high sensitivity of 9.33 μA μM^-1 cm^-2, with a linear range of 5-60 μM. The real sample analysis of the HQ analyte in a water sample showed recovery in the range of 97.45-102.61% with an RSD of 1%. These findings suggest that the PNT/CuO GCE sensor is a strong option for detecting the HQ analyte in real samples. Furthermore, the PNT/CuO GCE exhibited exceptional electrocatalytic activity for the HER (<i>η</i> = 330 mV and Tafel slope = 139 mV dec^-1), showing that the PNT/CuO GCE exhibits high activity as an electrocatalyst for H₂ generation.