Barium titanate nanoparticle-based disposable sensor for nanomolar level detection of the haematotoxic pollutant quinol in aquatic systems

Abstract

The deteriorating quality of water owing to the existence of toxic chemicals in ecological water sources due to industrial effluents has become a cause for concern these days. An electrocatalytic device was fabricated for the detection of the haematotoxic pollutant quinol (QL) using barium titanate nanoparticles (BaTiO₃ NPs). A sustainable co-precipitation method was employed to synthesize the BaTiO₃ NPs. Then, their physical characteristics were confirmed using techniques such as X-ray diffraction to elucidate their crystalline nature, scanning electron microscopy and high resolution transmission electron microscopy to study their surface morphology, and energy dispersive X-ray spectroscopy to analyze their elemental composition. The prepared BaTiO₃ NPs were applied over a disposable screen-printed electrode and used for the determination of QL with a wide dynamic response range (0.001–340 μM), low detection limit (0.009 μM) and excellent sensitivity (1.19 μA μM⁻¹ cm⁻²). The superior electrical conductivity of the BaTiO₃ NPs/SPCE is associated with a low s-value and high number of non-bridging oxygen ions present in the nanoparticle structure. The proposed sensor displays excellent selectivity, reproducibility and storage stability as a QL sensor. Additionally, the superior sensing performance of the BaTiO₃ NPs was effectively applied in water samples, with acceptable recovery values towards hazardous environmental pollutants.