Development of an ultrasensitive sensor for detecting metol in environmental water samples using ruddlesden-popper type layered perovskite (La2NiO4) combined with graphene oxide

• Published in: Water research (Oxford) 2025-04, Vol.273, p.122998, Article 122998
• Main Authors: Manimaran, Parthasarathi, Tamilalagan, Elayappan, Chen, Shen-Ming, Govindharaj, Abirami
• Format: Article
• Language: English
• Subjects: Calcium Compounds - chemistry; Electrochemical sensing; Electrochemical Techniques; Electrodes; Environmental Monitoring - methods; Graphite - chemistry; La2NiO4@GO nanocomposite; Lanthanum - chemistry; Limit of Detection; Nanocomposites - chemistry; Organic pollutant; Oxides - chemistry; P-methylamino phenol sulfate; Photoelectron Spectroscopy; Spectroscopy, Fourier Transform Infrared; Titanium - chemistry; Voltammetry; Water Pollutants, Chemical - analysis
• ISSN: 0043-1354; 1879-2448; 1879-2448
• DOI: 10.1016/j.watres.2024.122998

•Layered perovskite (La2NiO4) infused with GO sheet has used as active material for MTO sensing.•The sensor has a high sensitivity towards MTO detection with a LOD of 6.4 nM.•This electrochemical sensor has good stability, anti-interference, and reproducibility.•It has shown practical application to rapid MTO detection in water and urine sample. Metol (MTO), a commonly used photographic developer, has become an environmental pollutant due to its extensive use and subsequent release into water sources. The accumulation of MTO poses significant risks, including aquatic toxicity and potential bioaccumulation, leading to adverse effects on ecosystems. To address these environmental challenges, we developed a La₂NiO4 combined with graphene oxide (La₂NiO₄@GO) nanocomposite modified glassy carbon electrode (GCE) for the ultrasensitive detection of MTO. The La₂NiO₄ was synthesized via a hydrothermal method and subsequently integrated with graphene oxide through a sonochemical technique, with comprehensive characterization using Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and High-resolution transmission electron microscopy (HR-TEM). Electrochemical analysis revealed that the La₂NiO₄@GO-modified electrode exhibited a low charge transfer resistance of 20 Ω. Using differential pulse voltammetry (DPV), the electrode demonstrated a limit of detection (LOD) of 6.4 nM for MTO, with a high sensitivity of 10.84 µA µM⁻¹cm⁻² and excellent anti-inference property towards MTO tested along with interfering substances. The sensor was successfully applied to real environmental water samples and human urine samples, showing excellent recovery rates of MTO. This work underscores the potential of La₂NiO₄@GO-modified electrodes in monitoring and mitigating the environmental impact of MTO, contributing to a healthy environment. [Display omitted]