Metal oxide electrodes: A new frontier in electrochemical microplastic detection

Microplastic pollution has become a significant problem due to its widespread presence in aquatic ecosystems and its possible negative impacts on human beings and marine life. Traditional detection methods are often time-consuming, and their sensing activity still needs accurate quantification. Electrochemical sensing methods offer a promising alternative for the highly sensitive and quick detection of microplastics. This review explains the outlines of recent advancements in electrochemical sensing methods, with a focus on metal oxide electrodes. These electrodes have been recognized as promising platforms for microplastic detection owing to their relatively high chemical stability, large surface area, and superior conductivity. Various metal oxides, such as zinc oxide (ZnO), titanium dioxide (TiO₂), and iron oxide (Fe₃O₄), have been investigated for their suitability in these applications. This review discusses the principles and mechanisms underlying electrochemical sensing, including voltammetric and amperometric techniques. Key factors influencing the performance of metal oxide-based sensors, such as electrode morphology, surface functionalization, and sensor configuration, are examined. Recent developments in sensors, fabrication techniques, and strategies for enhancing sensitivity and selectivity are also highlighted. In addition, the review confronts the challenges, hurdles, and future directions in electrochemical sensing for microplastic detection, including the need for standardized protocols, validation of sensor performance in real-world samples, and integration into monitoring networks for environmental surveillance. Overall, metal oxide-based electrochemical sensing methods hold great promise for detecting microplastics in environmental samples. Continued research efforts aimed at optimizing sensor performance and addressing practical challenges will contribute to the development of reliable and cost-effective tools for microplastic monitoring and remediation.