Eco-friendly electrodeposition sensing of hydrogen peroxide based on Co@Ag/PPy bimetallic nanohybrid

Abstract

Hydrogen peroxide (H₂O₂) has practical applications in healthcare, food security, and environmental protection. The current study has been focused on creating H₂O₂ sensors using a bimetallic composition of polypyrrole/Cobalt-silver on indium tin oxide (ITO) through electrochemical fabrication. Composite hybrid materials comprising Co@Ag/PPy/ITO were successfully synthesized using chronoamperometry and pulsed electrodeposition techniques. The obtained electrode (Co@Ag/PPy/ITO) was studied using scanning electron microscopy (SEM), ultraviolet–visible, and cyclic voltammetry techniques. The energy-dispersive X-ray spectroscopy and SEM revealed that silver and cobalt nanoparticles were distributed on the PPy surface, forming fern-like structures. A detailed investigation of the electrochemical properties of the bimetallic composition was conducted using cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance spectroscopy. The amperometric method and CV were used to carry out the electrochemical detection of H₂O₂. The non-enzymatic H₂O₂ sensor exhibited an enhanced amperometry response, showing a higher sensitivity of 3.664 mA mM⁻¹ cm⁻² within a linear range spanning 0.12–2.36 mM. Notably, the sensor achieved a low detection limit of 1.985 μM (S/N = 3). Additionally, the nanocomposite hybrids demonstrated superior stability, repeatability, and reproducibility, making this sensor suitable for long-term use.