Application of pyrite and chalcopyrite as sensor electrode for amperometric detection and measurement of hydrogen peroxide

Abstract

The sensing performance of solid-state amperometric sensors based on natural sulfide minerals, i.e., pyrite and chalcopyrite, has been characterized for the detection and measurement of hydrogen peroxide (H₂O₂) in aqueous medium. The sensors showed a wide linear relationship range between response current and the concentration of H₂O₂ from 1.0 × 10⁻⁵ mol L⁻¹ to 1.0 × 10⁻² mol L⁻¹ and 1.0 × 10⁻⁴ mol L⁻¹ to 3.0 × 10⁻² mol L⁻¹ for pyrite and chalcopyrite, respectively. The limit of detection (LOD) was as low as 8.6 × 10⁻⁶ mol L⁻¹ and 5.2 × 10⁻⁵ mol L⁻¹ (S/N = 3), respectively. The electrodes exhibited great sensitivity, repeatability and short response time (less than 5 s). The results show that pyrite and chalcopyrite can be used as a natural, low cost, reliable and sensitive sensor for hydrogen peroxide detection, creating a new and high value application for the sulfide minerals.